Full-Mouth Adhesive Rehabilitation of a Severely Eroded Dentition: The Three-Step Technique. Part 1.

Transcription

1 CLINICAL APPLICATION Puliction Full-Mouth Adhesive Rehilittion of Severely Eroded Dentition: The Three-Step Technique. Prt 1. Frncesc Vilti, MD, DMD, MSc Senior Lecturer, Deprtment of Fixed Prosthodontics nd Occlusion School of Dentl Medicine, University of Genev Switzerlnd Urs Christoph Belser, DMD, Prof Dr med dent Chirmn, Deprtment of Fixed Prosthodontics nd Occlusion School of Dentl Medicine, University of Genev Switzerlnd Correspondence to: Dr Frncesc Vilti University of Genev, Deprtment of Fixed Prosthodontics nd Occlusion, Rue Brthelemy-Menn 19, 1203 Genev, Switzerlnd; e-mil: 30 VOLUME 3 NUMBER 1 SPRING 2008

2 VAILATI/BELSER Puliction Astrct Trditionlly, full-mouth rehilittion sed on full-crown coverge hs een the recommended tretment ptients ffected severe dentl erosion. Nowdys, thnks to improved dhesive techniques, the indictions crowns hve decresed nd more conservtive pproch my e proposed. Even though dhesive tretments simplify oth the clinicl nd lortory procedures, restoring such ptients still remins chllenge due to the gret mount of tooth destruction. To fcilitte the clinicin s tsk during the plnning nd execution of full-mouth dhesive rehilittion, n innovtive concept hs een developed: the three-step technique. Three lortory steps re lternted with three clinicl steps, llowing the clinicin nd the lortory technicin to constntly interct to chieve the most predictle esthetic nd functionl outcome. During the first step, n esthetic evlution is permed to estlish the position of the plne of occlusion. In the second step, the ptient s posterior qudrnts re restored t n incresed verticl dimension. Finlly, the third step reestlishes the nterior guidnce. Using the three-step technique, the clinicin cn trnsm full-mouth rehilittion into rehilittion individul qudrnts. This rticle illustrtes only the first step in detil, explining ll the clinicl prmeters tht should e nlyzed ee inititing tretment. (Eur J Esthet Dent 2008;3:30 44.) 31 VOLUME 3 NUMBER 1 SPRING 2008

3 CLINICAL APPLICATION Puliction Fig 1 ( nd ) Severely eroded dentition in 27-yer-old ptient. Ptients ffected severe dentl erosion often present with n extremely dmged dentition, especilly in the nterior mxillry qudrnt. The verticl dimension of occlusion (VDO) my hve decresed, nd supreruption my hve occurred. If erosion is not intercepted t n erly stge, fullmouth rehilittion my e required. According to the ville literture (cse reports only), the recommended therpy comprises oth extensive elective root cnl tretment nd full-crown coverge of lmost ll teeth. 1 3 However, this pproch my e too ggressive considering tht the popultion ffected erosion is generlly very young (Fig 1). When 14-yer-old ptient receives full-mouth conventionl rehilittion, such s in recently pulished report, 2 the following questions should e considered: How mny times will these crowns hve to e replced in the future, nd wht will e the prognosis of such teeth? How mny of the teeth will remin vitl? How mny will ecome nonrestorle (Fig 2)? Fig 2 Pnormic rdiogrph of 70-yer-old ptient with hevily restored dentition. The ptient received his first full-mouth rehilittion t the ge of VOLUME 3 NUMBER 1 SPRING 2008

4 VAILATI/BELSER Puliction The current literture does not nswer these questions. No long-term follow-up studies of similr cses re ville. Consequently, ee proposing conventionl full-mouth rehilittion to young individuls ffected erosion, clinicins should consider more conservtive pproches. In this context, improved dhesive techniques my e vlid lterntive, t lest to postpone more invsive tretments until the ptient is older. 4 7 The dhesive pproch preserves more tooth structure nd voids elective endodontic therpy. In ddition, in the uthors opinion, the esthetic outcome of teeth restored with onded porcelin restortions is superior to tht chieved with cemented crown restortions. Further, gingiv seems to interct etter with the mrgins of onded veneers thn with the mrgins of cemented crowns, resulting in less inflmmtion or drk colortions. However, while severl uthors hve documented long-term follow-up conventionl fixed prostheses, 8 17 there is lck of comprle long-term dt on full- mouth dhesive restortions. Consequently, the dete is still open on whether possily less durle dhesive rehilittion is preferle to longer-lsting ut more ggressive conventionl tretment. For this reson, clinicl tril is underwy t the University of Genev. All ptients ffected generlized erosion re systemticlly nd exclusively treted with dhesive techniques, using onlys the posterior region nd onded lminte veneers the nterior region. The gol is to evlute the longevity of dhesive rehilittions ee proposing this tretment s the new stndrd of cre. The three-step technique To chieve mximum preservtion of tooth structure nd the most predictle esthetic nd functionl outcomes, n innovtive concept hs een developed: the threestep technique (Tle 1). Three lortory steps re lternted with three clinicl steps, llowing the clinicin nd dentl Tle 1 The three-step technique Lortory Clinicl Mxillry vestiulr wxup Step 1: Esthetics Assessment of occlusl plne Posterior occlusl wxup Step 2: Posterior support Cretion of posterior occlusion t n incresed VDO Mxillry nterior pltl onlys Step 3: Anterior guidnce Reestlishment of finl nterior guidnce 33 VOLUME 3 NUMBER 1 SPRING 2008

5 CLINICAL APPLICATION Puliction technicin to constntly interct during the plnning nd execution of full-mouth dhesive rehilittion. In the first lortory step, insted of full-mouth wxup, the technicin is instructed to wx up only the vestiulr spect of the mxillry teeth (estheticlly driven wxup). Afterwrds, the clinicin will check if the wxup is cliniclly correct using mxillry vestiulr mockup (first clinicl step). During the second lortory step, the technicin focuses on the posterior qudrnts, creting posterior occlusl wxup to determine new VDO. The second clinicl step is to give the ptient stle occlusion in the posterior qudrnts t n incresed VDO, closely reproducing the occlusl scheme of the wxup. With the use of silicon keys duplicting the wxup, ll four posterior qudrnts will e restored with provisionl posterior composites. Finlly, the third step dels with the reconstruction of the pltl spect of the mxillry nterior teeth (restortion of the nterior guidnce) ee restoring the vestiulr spect with onded porcelin restortions. In this rticle, only the first step is discussed. Tretment plnning Unrelistic ptient expecttions re often contrindiction to dentl tretment. However, wht seems to e n unrelistic expecttion my in fct e poorly expressed expecttion or n expecttion tht is misunderstood the clinicin. Even when there is seemingly perfect three-wy communiction (ptient/clinicin/technicin), there is lwys potentil misunderstndings, especilly when deling with ptients who re ccustomed to viewing themselves with smll, eroded teeth. The importnce of predictle result tht stisfies oth the ptient nd clinicin cnnot e stressed enough in tody s world of estheticlly demnding ptients. Surprisingly, mny clinicins still decide on the esthetic outcome their ptients, nd thus the result seldom meets the ptient s expecttions. A structured strtegy to minimize such n esthetic defet is to devote sufficient time to educte ptients out the tretment options nd expected results. The first step of this three-step technique is conceived to gurntee tht the clinicin nd technicin s vision the plnned restortion is reflection of the ptient s true desires. Step 1: Mxillry vestiulr wxup nd ssessment of the occlusl plne Generlly, t the eginning of full-mouth rehilittion, the clinicin will provide the lortory technicin with the dignostic csts nd request full-mouth wxup. Since ech prmeter, such s incisl edges, teeth xes, teeth shpes nd sizes, occlusl plne, etc, is esily controlled, wxing oth the mxillry nd mndiulr rches is not difficult tsk. Clinicins should relize, however, tht lortory technicins will often ritrrily decide on these prmeters without seeing the ptients nd with misleding lck of reference points (eg, djcent intct teeth). Untuntely, decision sed only on dignostic csts is extremely risky, since dentl restortion tht ppers perfect on the cst my e cliniclly indequte. One method to ensure tht everyone is on the sme pge is the use of mockup, technique tht mkes it possile to nticipte the finl shpe of the teeth in the mouth. Severl uthors hve lredy 34 VOLUME 3 NUMBER 1 SPRING 2008

6 VAILATI/BELSER Puliction Fig 3 Frontl () nd profile () views of 45-yer-old ptient ffected gstric reflux. e the severe generlized tooth destruction s result of the dentl erosion. c d Fig 4 Both trditionl mockup (covering only the mxillry nterior teeth) ( nd ) nd mxillry vestiulr mock-up (from second premolr to second premolr) (c nd d) were used to evlute esthetics. With the trditionl mockup, the nterior teeth ppered too long, nd the ptient disliked their length nd shpe. Once the mockup ws extended to the premolrs, the ptient rted the sme nterior teeth s estheticlly plesing. proposed the use of mockup veneer restortions of nterior teeth. 18,19 In cses of severe generlized destruction of the dentition, mockup of only the nterior teeth could e misleding, since the teeth will pper inhrmonious with the unre- stored posterior teeth. Insted, mockup tht involves ll mxillry teeth my e more pproprite pproch (Figs 3 to 5). To otin mockup of ll mxillry teeth is not necessry t this initil stge to hve full mouth wx-up. In fct, the three-step 35 VOLUME 3 NUMBER 1 SPRING 2008

7 CLINICAL APPLICATION Puliction c Fig 5 Fcil views ee () nd fter ( nd c) the mxillry vestiulr mockup. Fig 6 ( nd ) Mxillry vestiulr wx-up. e tht the cingul nd the pltl cusps re not included. In this ptient, the vestiulr spects of oth the first mxillry molrs were intct nd thus not included in the wxup. technique proposes tht the technicin should wx up only the vestiulr surfce of the mxillry teeth. To sve time nd fcilitte the next clinicl step, neither the cingul of the nterior mxill nor the pltl cusps of the mxillry posterior teeth re included. In situtions where the vestiulr spect of the first molrs ws not ffected the erosion, the technicin my stop the wxup t the level of the premolrs (Fig 6). The mxillry second molr is never included in the wxup. At the completion of the mxillry vestiulr wxup, the first clinicl step (mxillry vestiulr mockup) is introduced so tht the clinicin cn confirm the direction tken the technicin. The fctors tht should e considered during this ssessment will now e discussed. Incisl edges Ptients re often shocked the incresed length of the incisors selected the clinicin nd technicin. After yers of seeing themselves with compromised dentition, mny ptients cnnot immedi- 36 VOLUME 3 NUMBER 1 SPRING 2008

8 VAILATI/BELSER Puliction c Fig 7 ( to c) When n incresed VDO is plnned, the position of the occlusl plne is decided ritrrily the technicin. Often, the otined spce is shred eqully etween the two rches, with consequent chnge of position of the occlusl plne (lower position). This ritrry decision cn compromise the esthetic outcome in ptients with preexisting reverse smile. tely dpt to more voluminous teeth. Often, ptients will eventully gree to such chnge if they re llowed to test the new teeth; however, some ptients will never ccept it. Clinicins cnnot impose their personl opinions onto their ptients, ut they cn try to guide the ptient in mking n inmed decision. The mockup represents n excellent opportunity ptients nd clinicins to truly understnd ech other s points of view. The mockup covering the teeth cn e shortened or lengthened (using flowle composite), nd their shpe cn e modified. If mjor chnges re mde, n lginte impression cn e tken to guide the technicin. Occlusl plne The innovtive spect of the three-step technique is the extension of the mockup to the vestiulr spect of the mxillry posterior teeth. The inclusion of the four premolrs is crucil, not only to visulize their uccl spect in comprison with the nterior teeth (vestiulr hrmony), ut lso to relte the plne of occlusion to the incisl edges. Mxillry incisl edges nd the occlusl plne should e in hrmony n optiml esthetic nd functionl result. In frontl, smiling view, the cusps of the posterior teeth should follow the lower lip nd e locted more cerviclly thn the incisl edges. Otherwise, n unplesnt, reverse smile is generted. When n increse of the VDO is nticipted in full-mouth rehilittion, the question of how to divide the extr interocclusl spce is generlly nswered shring the spce eqully etween the mndiulr nd mxillry rches. However, such decision is completely ritrry nd my led to repositioning of the occlusl plne t lower level thn the originl. Untuntely, in cses of erosion, the loss of tooth structure is often compensted supreruption, especilly in the mxillry posterior region nd mndiulr nterior region. One gol of fullmouth rehilittion should e the correction of such sitution. The technicin must know to wht extent the incisl edges cn e lengthened ee deciding on the occlusl plne s position nd wxing up the posterior qudrnts. A mxillry vestiulr mockup, which visulizes oth the incisl edges nd the uccl cusps of the posterior teeth, cn help verify the orienttion of the future occlusl plne (Figs 7 nd 8). 37 VOLUME 3 NUMBER 1 SPRING 2008

9 CLINICAL APPLICATION Puliction c d e f Fig 8 ( to f) Bee nd fter views of 27-yer-old ptient with history of gstric cid reflux. The mockup reestlished the hrmony etween the occlusl nd incisl plnes. 38 VOLUME 3 NUMBER 1 SPRING 2008

10 VAILATI/BELSER Puliction Fig 9 ( to c) If crown-lengthening surgery is nticipted, the mockup cn help visulize the mount of ttchment to e removed. c Hrmony with the mxillry molrs If the wxup is stopped t the level of the mxillry premolrs, it will e possile during the mxillry vestiulr mockup to evlute how the unrestored molrs will lend in with the restortion plnned the premolrs. The lip disply will lso preview the visiility of the uccl mrgins of the future restortions (onlys) the molrs. Emergence profile nd gingivl levels At the time of the wxup, the clinicin nd technicin cn determine whether crown lengthening is needed (Figs 9 nd 10). To confirm if mucogingivl surgery is necessry nd to wht extent, the technicin should wx the cervicl spect of the future restortions overlpping the gingiv of the cst. Consequently, the teeth of the mockup will cover the gingiv of the ptient. Their emergence profile will e slightly ltered, ut they will still provide good sense of the finl outcome to oth the clinicin nd the ptient. 39 VOLUME 3 NUMBER 1 SPRING 2008

11 CLINICAL APPLICATION Puliction It is not recommended to remove nd re Fig 10 ( nd ) After surgery, the mockup cn e used to evlute the outcome. Bsed on the lip disply, the teeth to e involved in the surgery cn e selected, nd the ptient cn mke n inmed decision whether to ccept the surgery. This presurgicl mockup cn e powerful tool to convince reluctnt ptients. In these cses, the compromised result could lso e visulized with nother mockup, this time without the gingivl overlp. Numer of teeth involved in the rehilittion Sometimes, ptients re not fully wre of the level of destruction of their dentition. Motivted primrily esthetics, ptients my elieve tht stisfctory result cn e chieved focusing only on the nterior teeth, nd thus they will not e interested in more comprehensive tretment pln. To void investing unnecessry time nd money, mxillry vestiulr mockup could e used. The mockup covering the posterior teeth could then e removed, leving the ptient with the mockup of only the six nterior teeth. While some of these ptients will still run wy s nticipted, others will e convinced to ccept the more extensive tretment. Clinicl steps the mxillry vestiulr mockup The mxillry vestiulr mockup is quickly nd esily fricted in the ptient s mouth nd offers the possiility to concretely visulize the finl outcome. A silicon key should e mde from the mxillry vestiulr wxup nd loded with tooth-colored mteril in the ptient s mouth (Fig 11). After its removl, ll vestiulr surfces of the mxillry teeth will e covered thin lyer of composite, reproducing the shpe selected the future restortions with the wxup. In our clinic, the mteril of choice is Protemp (3M ESPE), resin composite tht genertes limited exothermic rection nd is esy to dispense nd less suject to porosity thn polymethyl metcrylte. Since the cingul of the nterior teeth nd the pltl cusps of the posterior teeth re not included in the wxup, the silicon key will e stle in the mouth. It will lso e stilized on oth sides the unrestored second molrs (distl stops). Due to the key s close dpttion, excess mteril will e miniml nd esy to remove using sclpel or scler (Fig 12). 40 VOLUME 3 NUMBER 1 SPRING 2008

12 VAILATI/BELSER Puliction Fig 11 ( nd ) A silicone key of the mxillry vestiulr wxup is fricted nd loded with tooth-colored provisionl resin composite. Fig 12 ( to c) Due to the key s close dpttion, very little excess will e present fter its removl. e the shortening of the cnines (c) The mockup cn e esily modified in the ptient s mouth. C cement the mockup, ecuse this my rek it or distort its ppernce. The mockup is stilized excess mteril in the retentive res (interproximlly). The clinicin, however, should py prticulr ttention to tht excess, since it cn interfere 41 VOLUME 3 NUMBER 1 SPRING 2008

13 CLINICAL APPLICATION Puliction c d e f Fig 13 ( to f) Bee nd fter views of 27-yer-old femle ptient. Without the mockup, it ws difficult to evlute her smile, since she ws uncomtle showing her dmged teeth. 42 VOLUME 3 NUMBER 1 SPRING 2008

14 VAILATI/BELSER Puliction with the ptient s norml orl hygiene procedures. The chllenge is to open the gingivl emrsures just enough to llow dentl floss (eg, SuperFloss, Orl B) to pss through without jeoprdizing the strength of the mockup. It is lso recommended to ccurtely remove the excesses t the level of the uccl gingivl sulci to etter understnd the emergence profile nd gingivl hrmony of the future restortion. The ptient cn leve the office wering the mockup short time to show it to fmily memers nd friends. Due to its miniml thickness, the mockup will eventully rek off, mking it esily removle the ptient. After evluting the mxillry vestiulr mockup in the ptient s mouth (Fig 13), ny chnges cn e mde the technicin, who will then progress with the second lortory step. Conclusions Ptients ffected severe dentl erosion often present severely dmged dentition. However, the trditionl restortive pproch (full-mouth rehilittion with crowns) my e too ggressive this generlly young ptient popultion. In the uthors opinion, n dhesive pproch should e preferred to preserve tooth structure nd postpone the more invsive tretments until the ptient is older. Even though dhesive techniques simplify oth the clinicl nd lortory procedures, restoring such ptient still remins chllenge due to the mount of tooth destruction. To chieve mximum preservtion of the tooth structure nd the most predictle esthetic nd functionl outcome, n innovtive concept hs een developed: the three-step technique. The threestep technique is simplified pproch tht emphsizes interdisciplinry collortion etween the clinicin nd lortory technicin. In this rticle, only the first step of the technique ws descried. By using simple mxillry vestiulr mockup, the lortory technicin cn gin precious inmtion, nd the tretment of severely eroded dentition cn egin in less ritrry wy. The time-consuming initil dignosis should not discourge the clinicin, since the ptient s full prticiption in ny decision-mking process is extremely vlule. Indeed, llowing ptients to visulize the finl result ee tretment egins oth ressures them nd helps them ccept more comprehensive tretments. Acknowledgments The uthors would like to thnk Dr Pierre-Jenne Loup, School of Dentl Medicine, University of Genev, his expertise in prodontology The uthors lso thnk the lortory technicins nd cermists, Sylvn Crciofo nd Dominique Vinci, School of Dentl Medecine, University of Genev, the excellent lortory support. References 1. Kvour V, Kourtis SG, Zoidis P, Andritskis DP, Doukoudkis A. Full-mouth rehilittion of ptient with ulimi nervos. A cse report. Int 2005;36: Vn Roekel NB. Gstroesophgel reflux disese, tooth erosion, nd prosthodontic rehilittion: A clinicl report. J Prosthodont 2003;12: Bonill ED, Lun O. Orl rehilittion of ulimic ptient: A cse report. Int 2001;32: Hyshi M, Shimizu K, Tkeshige F, Eisu S. Restortion of erosion ssocited with gstroesophgel reflux cused norexi nervos using cermic lminte veneers: A cse report. Oper Dent 2007;32: Lussi A, Jeggi T, Schffner M. Prevention nd minimlly invsive tretment of erosions. Orl Helth Prev Dent 2004;2 Suppl 1: VOLUME 3 NUMBER 1 SPRING 2008

15 CLINICAL APPLICATION Puliction 6. Sundrm G, Brtlett D, Wtson T. Bonding to nd protecting worn pltl surfces of teeth with dentine onding gents. J Orl Rehil 2004; 31: Hstings JH. Conservtive restortion of function nd esthetics in ulimic ptient: A cse report. Prct Periodontics Aesthet Dent 1996;8: Vn Nieuwenhuysen JP, D hoore W, Crvlho J, Qvist V. Long-term evlution of extensive restortions in permnent teeth. Dent 2003;31: Wlton TR. An up to 15-yer longitudinl study of 515 metlcermic FPDs: Prt 1. Outcome. Int J Prosthodont 2002; 15: Wlton TR. A 10-yer longitudinl study of fixed prosthodontics: Clinicl chrcteristics nd outcome of single-unit metlcermic crowns. Int J Prosthodont 1999;12: Vlderhug J, Jokstd A, Amjornsen E, Norheim PW. Assessment of the peripicl nd clinicl sttus of crowned teeth over 25 yers. J Dent 1997;25: Vlderhug J. A 15-yer clinicl evlution of fixed prosthodontics. Act Odontol Scnd 1991;49: Krlsson S. Filures nd length of service in fixed prosthodontics fter long-term function. A longitudinl clinicl study. Swed Dent J 1989;13: Wlton JN, Grdner FM, Agr JR. A survey of crown nd fixed prtil denture filures: Length of service nd resons replcement. J Prosthet Dent 1986;56: Coornert J, Adriens P, De Boever J. Long-term clinicl study of porcelin-fused-togold restortions. J Prosthet Dent 1984;51: Schwrtz NL, Whitsett LD, Berry TG, Stewrt JL. Unservicele crowns nd fixed prtil dentures: Life-spn nd cuses loss of serviceility. J Am Dent Assoc 1970;81: Pjetursson BJ, Brgger U, Lng NP, Zwhlen M. A systemic review of the survivl nd compliction rtes of llcermic nd metl-cermic reconstructions fter n oservtion period of t lest 3 yers. Prt I: Single crowns. Clin Orl Implnts Res 2007;18 Suppl 3: Mgne P, Belser UC. Novel porcelin lminte preprtion pproch driven dignostic mock-up. J Esthet Restor Dent 2004;16: Belser UC, Mgne P, Mgne M. Cermic lminte veneers: Continuous evolution of indictions. J Esthet Dent 1997;9: VOLUME 3 NUMBER 1 SPRING 2008

16 Puliction

17 CLINICAL APPLICATION Puliction Full-Mouth Adhesive Rehilittion of Severely Eroded Dentition: The Three-Step Technique. Prt 2. Frncesc Vilti, MD, DMD, MSc Senior Lecturer, Dept of Fixed Prosthodontics nd Occlusion School of Dentl Medicine, University of Genev Switzerlnd Urs Christoph Belser, DMD, Prof Dr med dent Chirmn, Dept of Fixed Prosthodontics nd Occlusion School of Dentl Medicine, University of Genev Switzerlnd Correspondence to: Dr Frncesc Vilti University of Genev, Dept of Fixed Prosthodontics nd Occlusion, Rue Bthelemy-Menn 19, 1203 Genev, Switzerlnd; e-mil: 128 VOLUME 3 NUMBER 2 SUMMER 2008

18 VAILATI/BELSER Puliction Astrct Trditionlly, full-mouth rehilittion sed on full-crown coverge hs een recommended tretment ptients ffected severe dentl erosion. Nowdys, thnks to improved dhesive techniques, the indictions crowns hve decresed nd more conservtive pproch my e proposed. Even though dhesive tretments simplify oth the clinicl nd lortory procedures, restoring such ptients still remins chllenge due to the gret mount of tooth destruction. To fcilitte the clinicin s tsk during the plnning nd execution of full-mouth dhesive rehilittion, n innovtive concept hs een developed: the three-step technique. Three lortory steps re lternted with three clinicl steps, llowing the clinicin nd the lortory technicin to constntly interct to chieve the most predictle esthetic nd functionl outcome. During the first step, n esthetic evlution is permed to estlish the position of the plne of occlusion. In the second step, the ptient s posterior qudrnts re restored t n incresed verticl dimension. Finlly, the third step reestlishes the nterior guidnce. Using the three-step technique, the clinicin cn trnsm full-mouth rehilittion into rehilittion individul qudrnts. The present rticle focuses on the second step, explining ll the lortory nd clinicl steps necessry to restore the posterior qudrnts with defined occlusl scheme t n incresed verticl dimension. A rief summry of the first step is lso included. (Eur J Esthet Dent 2008;3: ) 129 VOLUME 3 NUMBER 2 SUMMER 2008

19 CLINICAL APPLICATION Puliction c Fig 1 ( to c) Clinicl views of 60-yer-old ptient ffected generlized dentl erosion. For yers the ptient suffered from gstric esophgel reflux. At this lte stge full-mouth rehilittion is inevitle. Despite the dvnced loss of tooth structure, ll teeth re still vitl. Trditionlly, full-mouth rehilittion hs een the recommended tretment ptients ffected generlized severe dentl erosion. However, restortive concept comprising full-crown coverge of lmost ll teeth nd extensive elective root cnl tretment my e too ggressive this generlly very young popultion of ptients. 1 3 With current improved dhesive techniques, the indictions crowns hve decresed nd more conservtive pproch my e proposed, to preserve tooth structure nd to postpone more invsive tretments until the ptient is older. 4 8 In order to test the hypothesis tht such concept cn predictly rech the specific tretment ojectives, clinicl tril testing fully dhesive pproch is underwy t the University of Genev. All ptients ffected generlized dvnced dentl erosion re systemticlly nd exclusively treted with dhesive techniques, using onlys the posterior region nd comintion of fcil onded porcelin restortions (BPRs) nd pltl composite restortions the nterior mxillry region. The gol of this prospective clinicl study is to evlute the longevity of dhesive rehilittions, ee proposing this tretment option s the new stndrd of cre. Despite the tendency dhesive modlities to rther simplify the involved clinicl nd lortory procedures, tretment of such ptients still remins chllenge ecuse of the significnt mount of tooth destruction (Fig 1). 130 VOLUME 3 NUMBER 2 SUMMER 2008

20 VAILATI/BELSER Puliction Tle 1 The three-step technique Lortory Clinicl Mxillry vestiulr wxup Step 1: Esthetics Assessment of occlusl plne Posterior occlusl wxup Step 2: Posterior support Cretion of posterior occlusion t n incresed VDO Mxillry nterior pltl onlys Step 3: Anterior guidnce Reestlishment of finl nterior guidnce To fcilitte the clinicin s tsk during the plnning nd execution of full-mouth dhesive rehilittion, structured, innovtive concept hs een developed: the three-step technique (Tle 1). Three lortory steps re lternted three distinct clinicl steps, llowing the clinicin nd the lortory technicin to constntly interct nd thus to chieve the most predictle esthetic nd functionl outcome. The first step of the concept hs een previously descried in detil. 9 The present rticle focuses on the second step, explining ll the lortory nd clinicl steps necessry to restore the posterior qudrnts with defined occlusl scheme t n incresed verticl dimension. A rief summry of the first step is lso included. Full-mouth wxup: crucil or ritrry tool in the determintion of the plne of occlusion? Ptients ffected severe dentl erosion often present with n extremely dmged dentition, not infrequently mking clinicins hesitte to undertke such n ex- tended rehilittion. Trditionlly, one of the first steps consists of providing the lortory technicin with dignostic csts, nd requesting full-mouth wxup. A fullmouth wxup should guide the clinicin in plnning the tretment so tht the most esthetic nd functionl result is chieved respecting the principle of miniml invsiveness, ie, miniml tooth preprtion. Clinicins should relize, however, tht technicins will often ritrrily decide on numerous importnt dentl prmeters (eg, occlusl plne, incisl edge position) without seeing the ptients, nd with n often misleding lck of reference points (eg, djcent teeth). The fct tht the resulting finl rehilittions often do not reflect the initil full-mouth wxups confirms this sttement. In the uthors opinion, the most misjudged prmeter in full-mouth wxup is the position of the occlusl plne. In cse of full-mouth rehilittion t n incresed verticl dimension of occlusion (VDO), the gined interocclusl spce is generlly shred eqully etween the 131 VOLUME 3 NUMBER 2 SUMMER 2008

21 CLINICAL APPLICATION Puliction mndiulr nd the mxillry posterior teeth, to minimize tooth preprtion in oth rches. However, such decision is completely ritrry, nd the repositioning of the occlusl plne t lower level thn the originl my led to compromised esthetic result. In order to chieve n optiml esthetic outcome, oth the mxillry incisl edges nd the occlusl plne should e in hrmony. In frontl, smiling view, the vestiulr cusps of the mxillry posterior teeth should follow the lower lip nd e locted more cerviclly thn the incisl edges of the nterior dentition. Otherwise, n unplesnt, reverse smile is generted. Thus, to determine the correct distriution of the interocclusl spce gined the increse of VDO, it is mndtory to determine first the optiml position of the mxillry incisl edges of the plnned finl restortions. In ptients where the mxillry nterior teeth cnnot e lengthened sufficiently on their incisl spect to compenste n excessively low occlusl plne, ll the spce otined hs to e used exclusively the restortion of the mndiulr posterior teeth, which in turn will require more ggressive tooth preprtion of the mxillry posterior teeth. Advnced generlized dentl erosion frequently leds to supreruption of oth the mxillry posterior sextnts nd the mndiulr nterior segment, cusing so-clled reverse smile (Fig 2). Logiclly, in these ptients, the position of the occlusl plne cnnot e further lowered, unless there is certitude tht the incisl edges of the mxillry nterior teeth will e sufficiently lengthened to correct the reverse smile. An dditionl prolem inherent to this prticulr type of ptient is tht they re used to perceiving themselves with smller teeth. As consequence, not ll of them will redily ccept hving their nterior teeth restored with dded incisl volume. Hence communiction with the ptient ecomes of prmount importnce to void esthetic misunderstndings. Bee strting the full-mouth rehilittion, it is recommended to determine to wht extent the ptient will ccept lengthening of the nterior mxillry teeth, so tht the finl esthetic outcome will e well defined nd the required mount of preprtion of the mxillry posterior teeth cn e ccurtely plnned. Step 1: Lortory nd clinic The first step of the three-step technique is conceived to gurntee tht oth the clinicin s nd the lortory technicin s vision of the plnned restortion is reflection of the ptient s true desires. With the introduction of the first clinicl step, the technicin will not complete potentilly incorrect full-mouth wxup. In fct, the first lortory step proposes to wx up only the vestiulr surfces of the mxillry teeth. At this stge, where much of the relevnt inmtion is still missing, it is not dvisle to invest time in more comprehensive wxup. Susequently, the inmtion represented the mxillry vestiulr wxup will e picked up mens of precise silicone key (Fig 3). The ptient is then scheduled clinicl ppointment where mxillry vestiulr mockup is directly fricted in the mouth (first clinicl step). The clinicin will lod the silicone key with tooth-colored utopolymerizing resin composite mteril nd position in the ptient s mouth. After its removl, ll vestiulr surfces of the mxillry teeth will e covered thin lyer of 132 VOLUME 3 NUMBER 2 SUMMER 2008

22 VAILATI/BELSER Puliction c Fig 2 ( to c) An unplesent reverse smile is present when the position of the incisl edges of the mxillry nterior dentition is more cervicl thn the occlusl plne, s pprent in these three ptients ffected severe dentl erosion. c Fig 3 ( to c) First lortory step: Mxillry vestiulr wxup. The technicin is instructed to wx up only the vestiulr spect of the mxillry teeth. Neither the cingul nor the pltl cusps of the mxillry posterior teeth re included t this stge. A silicone key is then fricted nd will susequently e loded with tooth-colored resin composite mteril nd repositioned in the ptient s mouth the friction of mxillry mockup. c Fig 4 First clinicl step: Mxillry vestiulr mockup. Clinicl views ee () nd fter ( nd c) completion of the dignostic mockup. Mucogingivl surgery ws permed to cover the mrked gingivl recessions on the mxillry left cnine nd premolrs. e tht the mockup covers only the incisl edges nd the vestiulr cusps of the mxillry teeth. composite, reproducing the shpe defined the future restortions the lortory technicin. The descried, fully reversile reconstruction of the vestiulr cusps of the mxillry posterior teeth nd the incisl edges of the nterior teeth llows visuliztion of the future plne of occlusion. Additionl inmtion is lso otined, s explined in previous rticle, 9 most importntly the ptient s consensus regrding the plnned finl esthetic outcome (Figs 4 nd 5). After completion of the first step, either ml cceptnce the ptient is o- 133 VOLUME 3 NUMBER 2 SUMMER 2008

23 CLINICAL APPLICATION Puliction c d Fig 5 ( to d) These photogrphs present the sme ptient s shown in Fig 4. Owing to the mxillry vestiulr mockup (), the orienttion of the future occlusl plne cn e visulized, nd the esthetic direction tken the technicin greed with the ptient. Generlly, ptients pprecite the plnned tretment ojective eing presented to them so clerly t n erly stge nd ee ny irreversile mesures hve een tken. tined, or new guidelines chnges re wrded to the technicin, who cn then progress with the complete wxup of the posterior qudrnts. Bee continuing ny further with the three-step technique, it is importnt to ddress two topics specificlly, which in the cse of full-mouth rehilittion re still controversil: centric reltion nd verticl dimension of occlusion. Centric reltion: centric occlusion dilemm In the presence of generlized dvnced dentl erosion, which often significntly ffects occlusl morphology in the posterior segments of the dentition s well s nterior guidnce, the clinicin fces the dilemm whether to restore the ptient in centric reltion (CR) or in mximum intercusption position (MIP). According to numerous clssic rticles pulished in the field of Gnthology, CR is recommended s the only cceptle position when it comes to full-mouth rehilittions, since it is considered the only reproducile one. This concept ws developed conventionl full-mouth rehilittions, when ll the teeth were going to e restored mens of full coverge (crowns or fixed dentl prostheses) nd when working ex- 134 VOLUME 3 NUMBER 2 SUMMER 2008

24 VAILATI/BELSER Puliction Fig 6 Mounted study csts of sme ptient rticulted in MIP () nd in CR (), fter complete full mouth wxup. While the CR position cn e desirle in ptients with clss III molr occlusion, in ptients with clss II, s this prticulr ptient, it poses n occlusl dilemm. The future restortions on the nterior teeth would never e in contct (no nterior guidnce) unless unnturl oversized cingul were creted. e the excessive horizontl overlp () generted the comintion of the CR position nd the increse of VDO. tensively on oth rches t the sme time hd n elevted risk of losing ll intermxillry reference points. An dditionl rgument CR ws tht ptients treted under extended locl nesthesi were unle to collorte during the occlusl djustments. Currently, there is n incresing trend towrds minimizing the necessity complicted, time-consuming clinicl procedures on the one hnd, nd reducing the numer of full crown restortions on the other hnd, prticulrly when treting young ptients. Consequently, the new clinicl pproch (full-mouth dhesive rehilittion) the tretment of dvnced generlized erosion consists exclusively of posterior onlys nd nterior BPRs, nd is strtegiclly plnned in wy tht llows rehilittion of ptients qudrnt-wise insted of restoring oth dentl rches simultneously. In dynmic rehilittion process, where two key prmeters of functionl occlusion, ie, VDO nd interrch reltion, re constntly mintined the contrlterl side of the mouth, using CR s lndmrk reference of occlusion my not e so crucil. Furthermore, in cses of severe dentl erosion, the pltl spect of the mxillry teeth is often compromised; fter the enmel is lost, the exposed dentin is suject to ccelerted wer, which leds to pronounced concve morphology nd not infrequently to wekening nd frcture of the incisl edges. To stop the progression of the descried tooth destruction (erosion nd ttrition), the exposed remining dentin should e efficiently protected. Due to the supreruption of the nterior qudrnts, n increse of VDO is mndtory to restore the originl tooth m. However, in ptients with clss II molr occlusion, the comintion of incresed VDO nd CR position my set the nterior teeth significntly prt nd this cn led to n sence of nterior guidnce. 135 VOLUME 3 NUMBER 2 SUMMER 2008

25 CLINICAL APPLICATION Puliction Since it is not recommended to sustntilly increse the incisl length of the mndiulr nterior teeth (generlly supererupted in cses of dvnced generlized dentl erosion), nterior contcts cn logiclly only e re-estlished incresing the size of the mxillry cingul. In fct, severl of the ptients ffected severe generlized erosion treted t our clinic presented clss II molr occlusion with mjor discrepncy etween MIP nd CR. Thus it ws preferred to restore their occlusion in MIP nd to estlish nterior contcts without the necessity of creting oversized mxillry cingul (Fig 6). Furthermore, to evlute if under the previously descried conditions nd strictly following the three-step technique the use of CR s the interrch reltionship of reference is not prerequisite, the decision ws mde to restore ll the ptients ffected severe erosion in MIP. From the preliminry dt collected so fr, no significnt dverse effects hve een encountered tht would question the choice of using MIP. The incresed VDO dilemm: how much nd how to test? In ptients ffected severe generlized erosion, the question of whether VDO hs eventully decresed during this pthologicl process is difficult to nswer, s severl compenstory mechnisms, eg, supereruption of the lveolr process, my hve occurred. It is lso cliniclly quite irrelevnt. An increse of VDO is lwys mndtory, in order to reduce the need sustntil tooth preprtion nd to void the necessity of elective endodontic tretments. However, ny increse of VDO should e miniml so it is tolerted the ptient, nd gurntees t the end of the rehilittion the preservtion or re-estlishment of functionl nterior interrch contcts required nterior guidnce. Furthermore, the new VDO should lwys e tested cliniclly, ee irreversile tretments egin, since it is selected ritrrily on the rticultor. In this context, trditionl nd fully reversile pproch consists of the use of n occlusl gurd, which requires complince of the ptient. However, considering the ctive lifestyle of most people, it is rther nïve to expect tht ptients will wer such n occlusl gurd 24 hours dy severl months. A more relistic pproch my e the use of interim restortions. In the cse of dhesive rehilittion, the dentl technicin could fricte provisionl composite onlys, which would susequently e onded to the teeth, including the pltl spects of the mxillry nterior dentition. There re severl disdvntges to this method, such s the ssocited dditionl l fees. Furthermore, it my in mny instnces not e truly reversile pproch, since it could require some tooth preprtion to ssure miniml thickness of the onlys. The third possiility clinicl testing of the fesiility of n ritrrily chosen increse of VDO is the use of direct composites. However, free-hnd direct composites re very time consuming, prticulrly if the clinicin ims to duplicte exctly the occlusl scheme determined wxup on the mounted study csts. It should e repeted tht not only the posterior, ut lso the nterior teeth should e involved in the tretment in order to increse the VDO nd to recrete dequte nterior guidnce. The respective result my e disppointing, especilly if the clinicin expects to position the mndile in CR nd to estlish simultneously stle 136 VOLUME 3 NUMBER 2 SUMMER 2008

26 VAILATI/BELSER Puliction Fig 7 ( to c) Second lortory step: Posterior occlusl wxup. The lortory technicin wxes only the occlusl surfces of the premolrs nd the first molrs in ech posterior qudrnt of the mxillry nd mndiulr csts. Bsed on this wxup, four independent trnslucent silicone keys will e fricted. c occlusl contcts t the identicl VDO tht hd een previously selected on the rticultor, tsk tht is generlly considered lmost impossile. All the three of the ove techniques tht hve een proposed to test n increse of VDO hve some mjor drwcks. The dilemm of how to trnsfer efficiently nd correctly the new occlusion defined with the wxup remins. As consequence, the second step of the threestep technique proposes n esy nd reversile pproch to estlish new posterior support nd to test the dpttion of the ptient to this new VDO. This pproch, comining the dvntges of the ovementioned techniques, llows friction of fixed occlusl gurd, mde of splinted composite onlys, directly fricted in the mouth. Step 2: Lortory posterior occlusl wxup At the eginning of the tretment, the two mxillry nd mndiulr csts re mounted on semi-djustle rticultor with fceow in MIP. During the first step, the technicin permed vestiulr wxup on the mxillry cst, nd the position of the plne of occlusion ws susequently vlidted cliniclly. For ech ptient, the new VDO is decided ritrrily on the rticultor, tking into considertion the posterior teeth, where the mximum increse is desirle to mintin mximum of minerlized tissue, nd the 137 VOLUME 3 NUMBER 2 SUMMER 2008

27 CLINICAL APPLICATION Puliction c d Fig 8 ( to d) Wxup modifictions ee the friction of the trnslucent silicone keys. It is necessry to remove the wx from the mxillry cnines, so tht the key will etter e dpted in the ptient s mouth (cnine s mesil stop). nterior teeth, which should not e set too fr prt to jeoprdize the recretion of nterior contcts nd the relted nterior guidnce. Once the increse of the VDO is estlished nd the plne of occlusion vlidted, it is esy the technicin to wx up completely the occlusl surfces of the posterior teeth. The second lortory step, however, proposes only to wx up the occlusl surfces of the two premolrs nd the first molr in ech sextnt (Fig 7). The pltl spect of the mxillry cnines my lso e wxed t this stge to etter select the cusp shpe nd inclintion in reltion to the occlusl scheme selected (eg, cnine guidnce or group function). In more complex cses (shllow future nterior guidnce), the technicin my e oligted to wx up ll the cingul of the mxillry nterior teeth s well, to verify the disclusion of the posterior qudrnts in protrusion. Generlly, there is no need to wx up the mndiulr nterior teeth, since they re often only minimlly ffected the erosion. At completion of the posterior occlusl wxup, the technicin will fricte ech qudrnt one key, mde of trnslucent silicone (Elite Trnsprent, Zhermck). These keys will e used in the second clinicl step introrlly to fricte direct composites, reproducing the wxup very closely. 138 VOLUME 3 NUMBER 2 SUMMER 2008

28 VAILATI/BELSER Puliction c d Fig 9 ( to d) Introrl preprtion of posterior mxillry sextnt direct onding procedure: The two premolrs nd the first molrs ech posterior qudrnt re etched, nd priming nd onding gents re pplied. Cre is tken to isolte the djcent teeth with mtrices. Some modifictions of the wxup re susequently crried out to fcilitte the next clinicl step, ee producing the keys (Fig 8): The wx is crefully removed from the uccl nd the lingul surfces of the posterior teeth of the csts, so tht in turn ech key will e in close contct to the cervicl spect of the teeth in the ptient s mouth. As consequence, less excess resin composite my flow into the gingivl sulcus nd fewer introrl djustments will e necessry. The wx should lso e removed, if present, from the cnines, since they will serve s mesil stop to stilize the key introrlly. Step 2: Clinicl posterior interim composites The second clinicl step siclly consists of the friction of posterior composite onlys, directly permed in the ptient s mouth, thnks to the specil trnsprent keys duplicting the occlusl wxup. The two premolrs nd the first molrs of ech qudrnt re cid-etched, followed ppliction of primer nd ond (Optiond FL, Kerr) (Fig 9). In the uthors experience, even in cses of severe exposure of dentin, there is no need to nesthetize the ptient ee pplying the etching gent. The clinicin will then lod ech trnslucent key with composite, position it in the 139 VOLUME 3 NUMBER 2 SUMMER 2008

29 CLINICAL APPLICATION Puliction Fig 10 ( nd ) Second clinicl step: interim posterior composite. The trnslucent silicone key, duplicting the occlusl wxup, is loded with resin composite nd positioned in the mouth. The key is well stilized the cnine nd the second molr (mesil nd distl stops). Owing to the trnslucency of the silicone, the composite cn e polymerized through the key. Fig 11 ( nd ) The posterior provisionl resin composite is esily nd quickly fricted, with miniml excess requiring removl. A composite shde tht is slightly different from the remining dentition should e selected to fcilitte the future removl of these provisionl restortions. e tht in this ptient the clinicin hs filled the interproximl spces with teflon to reduce excess resin composite in the emrsures. Fig 12 ( nd ) Since the second molrs re not restored with interim resin composite, they serve s vlule indiction of the increse of VDO, once the respective csts re rticulted. Fig 13 Even though the occlusl ccess to the interproximl res is locked the splinted posterior interim composites, the gingivl emrsures re still open to llow clening with Superfloss. 140 VOLUME 3 NUMBER 2 SUMMER 2008

30 VAILATI/BELSER Puliction ptient s mouth, nd polymerize the composite through the key (Fig 10). Since the keys, mde of trnslucent silicone, re not s rigid s desired, it is crucil not to use too viscous resin composite (such s Tetric EvoCerm, Ivoclr Vivdent), or to lod the key excessively. To void distortion, the composite should e pre-wrmed, nd miniml quntity of mteril should e plced in the key, just enough the new volume of the occlusl surfces. At this stge, the second molrs re not included in the occlusl wxup, nor will they e restored with provisionl occlusl composite due to the following resons (Fig 12): to ssure the presence of stle distl occlusl stop ccurte positioning of the trnslucent keys during the friction of the posterior interim composites to cknowledge the fct tht three posterior teeth re considered sufficient to estlish stle posterior support in ech sextnt to hve reference indicting the mount of increse of VDO. Implementtion of this technique includes splinting the three posterior teeth involved, thus locking the occlusl ccess of two interproximl contcts res nd preventing the use of dentl floss. Adequte orl hygiene, however, is possile since the gingivl emrsures re kept open nd Superfloss cn e used with lterl pth of insertion (Fig 13). As stted ove, the originl models of the ptient re mounted in MIP nd the increse in VDO is decided on the rticultor. Despite the fct tht the rticultor's hinge xis is going to e different from the ptient's, in our experience it does not generte sufficiently different occlusl contcts on the composite resin to require the mounting of the csts in CR. Minor occlusl djustments should e expected implementing this technique, ut normlly, if the wxup is correctly permed, nd the keys ccurtely fricted nd positioned in the mouth, the time required the djustment is limited (Fig 14). In ddition, since there is normlly no need to nesthetize the ptient, control of the oc- Fig 14 ( nd ) A different ptient, ee nd fter the second step of the three-step technique. Miniml occlusl djustments re expected if the previous steps re permed correctly (eg, posterior occlusl wxup, trnslucent key friction, loding of the keys). e tht the composites do not extend to the cervicl third of the teeth, thnks to the respective modifictions of the wxup ee the key friction. The resulting visile trnsition step cn e smoothed with polishing ruer wheel. 141 VOLUME 3 NUMBER 2 SUMMER 2008

31 CLINICAL APPLICATION Puliction c d Fig 15 ( to d) A 29-yer-old ptient ee nd fter the second clinicl step of the three-step technique. Even in cses of extensive dentine exposure, dentl nesthesi is not required during this step. Fig 16 ( nd ) Close-up view of the previous ptient. Existing mlgm restortions cn e removed (tooth 36) or left in plce nd covered with the interim resin composite (tooth 26). 142 VOLUME 3 NUMBER 2 SUMMER 2008

32 VAILATI/BELSER Puliction cisl edge position, modifying the vestiulr cusps of the posterior provisionl composites. Finlly, their presence will fcilitte the occlusl djustments of the finl restortions plced in the opposite qudrnt. The lortory technicin could decide to fricte the ltter to the perfect m nd ll the occlusl djustments could e crried out on the opposite provisionl posterior composites. The second clinicl step hs een conceived to simplify the clinicin s work, without compromising the finl outcome of the full mouth rehilittion. In this cse, it ws decided not to ttempt to restore the nterior teeth with provisionl resin composite. In the uthors experience the increse of VDO is well tolerted (ecuse miniml) the ptients even when n nterior open ite is creted temporrily. Some speech impirments could e nticipted. However, ptients inmed ee tretment usully del very well with this prolem (Figs 17 to 19). Currently, there is no consensus of the time necessry to test the comt of the ptient with respect to new, incresed VDO, nd ech clinicin ppers to decide sed on personl opinion rther thn on clusion will e fcilitted nd consequently more ccurte. This fixed occlusl gurd hs the mjor dvntge tht the complince of the ptient is 100% in terms of testing the incresed VDO. Since no tooth preprtion is requested the friction of the posterior occlusl composites, the tretment cn e considered completely reversile; if signs nd/or symptoms of temporomndiulr dysfunction rise, the initil sttus could e re-estlished grinding off the occlusl composites. These composite onlys re ment to e provisionl, nd they will e replced (with finl composite or cermic onlys) fter the nterior qudrnts re definitely restored (step 3 of the three-step technique) (Fig 15). This is one of the resons tht the use of ruer dm is not vitl during this prticulr step, nd the removl of existing functioning restortions (eg, old mlgm restortions) is not strictly required. Another dvntge of these interim composites is their potentil modifiction. After, exmple, completion of the restortion of the mxillry nterior teeth, it is still possile to djust the position of the occlusl plne with respect to the new in Fig 17 ( nd ) Sme ptient s shown in Fig 12. After completion of the second clinicl step the ptient is restored t n incresed VDO (). e the slight nterior open ite tht hs een generted. 143 VOLUME 3 NUMBER 2 SUMMER 2008

33 CLINICAL APPLICATION Puliction Fig 18 ( nd ) Another exmple of ptient ffected severe dentl erosion, restored ccording to the three-step technique. At this stge the posterior qudrnts (except the second molrs) were restored with interim posterior resin composite (second clinicl step). c d Fig 18 (c nd d) Frontl view t the new verticl dimension of occlusion shown in Fig 18. Normlly, ptients who were inmed eehnd del well with the resulting nterior open ite. Fig 19 Close-up view of the previous ptient s right side. Initil sttus () nd fter the second clinicl step (). The ptient underwent mucogingivl surgery, which reveled distinct clss V lesions, previously locted slightly sugingivlly. 144 VOLUME 3 NUMBER 2 SUMMER 2008

34 VAILATI/BELSER Puliction scientific evidence. At the University of Genev, the protocol suggests witing one month. This is completely ritrry nd experimentl choice. Once the ptient feels comtle nd neither signs nor symptoms of temporomndiulr dysfunction pper, the cceptnce of the new VDO cn e confirmed, nd the third step (the cretion of the nterior guidnce) cn e undertken. If the clinicin is concerned out leving the ptient without nterior contcts nd thus without functionl nterior guidnce during the testing phse of the newly introduced, incresed VDO, the third step could e initited more rpidly. Finlly, the technicin will concentrte on the nterior teeth. Bsed on the degree of destruction, the pltl spect of the nterior teeth will e restored (direct or indirect resin composites), representing the third nd lst clinicl step of the three-step technique. At this point the ptient will e stle from point of view of occlusion. The only definitive restortions re the pltl reconstructions. The vestiulr/incisl spects of the nterior mxillry teeth, s well s the reminder of the posterior teeth, still need to e treted mens of permnent restortions. Conclusions The restortive therpy of dentl erosion should e sed on minimlly invsive pproch, even in the cse of extensive loss of tooth structure. Adhesive techniques cn help the clinicin in rehilitting this type of ptient in the most conservtive mnner. The three-step technique is structured pproch to chieve full-mouth dhesive rehilittion with the most predictle result, the miniml mount of tooth preprtion, nd the highest level of ptient cceptnce. The gol of this technique is to temporrily restore compromised dentition t new VDO, implementing directly onded posterior composite restortions. With stle posterior support, the nterior teeth cn susequently e restored esily, gin using exclusively dhesive techniques. Once the nterior contcts nd n nterior guidnce re re-estlished, the replcement of the posterior provisionl resin composites cn egin. Owing to the presence of the provisionl posterior composites, the fullmouth rehilittion cn e plnned ccording to qudrnt-wise pproch. Restoring ptient qudrnts hs enormous prcticl dvntges oth ptient nd clinicin, since fewer ppointments re necessry. Neither multiple nesthetic injections nor difficult full mouth impressions re required. Since the contrlterl prt of the mouth gurntees stle occlusion, ptients feel comtle throughout the whole ctive tretment phse up to the delivery of the finl restortions. In this rticle, the second step of the three-step technique hs een discussed in detil, including the friction of the directly onded provisionl posterior composites. Acknowledgments The uthors would like to thnk the lortory technicins nd cermists Alwin Schönenerger, Ptrick Schnider nd Sylvin Crciofo their enthusistic collortion nd meticulous execution of the lortory work presented in this rticle. 145 VOLUME 3 NUMBER 2 SUMMER 2008

35 CLINICAL APPLICATION Puliction References 1. Kvour V, Kourtis SG, Zoidis P, Andritskis DP, Doukoudkis A. Full-mouth rehilittion of ptient with ulimi nervos. A cse report. Int 2005;36: Vn Roekel NB. Gstroesophgel reflux disese, tooth erosion, nd prosthodontic rehilittion: A clinicl report. J Prosthodont 2003;12: Bonill ED, Lun O. Orl rehilittion of ulimic ptient: cse report. Int 2001;32: Hyshi M, Shimizu K, Tkeshige F, Eisu S. Restortion of erosion ssocited with gstroesophgel reflux cused norexi nervos using cermic lminte veneers: cse report. Oper Dent 2007;32: Aziz K, Zieert AJ, Co D. Restoring erosion ssocited with gstroesophgel reflux using direct resins: cse report. Oper Dent 2005;30: Lussi A, Jeggi T, Schffner M. Prevention nd minimlly invsive tretment of erosions. Orl Helth Prev Dent 2004;2(Suppl 1): Sundrm G, Brtlett D, Wtson T. Bonding to nd protecting worn pltl surfces of teeth with dentine onding gents. J Orl Rehil 2004;31: Hstings JH. Conservtive restortion of function nd esthetics in ulimic ptient: cse report. Prct Periodontics Aesthet Dent 1996;8: Vilti F, Belser UC. Full mouth dhesive rehilittion of severely eroded dentition: the three step technique. Prt I. Eur J Esthet Dent 2008;1: Sturt CE, Golden IB. The History of Gnthology. CE Sturt Gntologicl Instruments. 1981;13 32, Grnger ER. Prcticl Procedures in Orl Rehilittion. Phildelphi: Lippincott, 1962: McCollum BB. Fundmentls involved in prescriing restortive dentl remedies. Dentl Items Interest, VOLUME 3 NUMBER 2 SUMMER 2008

36 Puliction

37 CLINICAL APPLICATION Puliction Full-Mouth Adhesive Rehilittion of Severely Eroded Dentition: The Three-Step Technique. Prt 3. Frncesc Vilti, MD, DMD, MSc Senior Lecturer, Dept of Fixed Prosthodontics nd Occlusion School of Dentl Medicine, University of Genev, Switzerlnd Privte prctice, Genev Dentl Studio, Switzerlnd Urs Christoph Belser, DMD, Prof Dr med dent Chirmn, Dept of Fixed Prosthodontics nd Occlusion School of Dentl Medicine, University of Genev Switzerlnd Correspondence to: Dr Frncesc Vilti University of Genev, Dept of Fixed Prosthodontics nd Occlusion, Rue Bthelemy-Menn 19, 1203 Genev, Switzerlnd; e-mil: 236 VOLUME 3 NUMBER 3 AUTUMN 2008

38 VAILATI/BELSER Puliction Astrct Dentl erosion is frequently underestimted pthology tht nowdys ffects n incresing numer of younger individuls. Often the dvnced tooth destruction is the result of not only difficult initil dignosis (e.g. multifctoril etiology of tooth wer), ut lso lck of timely intervention. A clinicl tril testing fully dhesive pproch ptients ffected severe dentl erosion is underwy t the School of Dentl Medicine of the University of Genev. All the ptients re systemticlly nd exclusively treted with dhesive techniques, using onlys in the posterior region nd comintion of fcilly onded porcelin restortions nd indirect pltl resin composite restortions in the nterior mxillry region. To chieve mximum preservtion of tooth structure nd predict the most esthetic nd functionl outcome, n innovtive concept hs een developed: the threestep technique. Three lortory steps re lternted with three clinicl steps, llowing the clinicin nd the dentl technicin to constntly interct during the plnning nd execution of full-mouth dhesive rehilittion. In this rticle, the third nd lst step of the three-step technique hs een descried in detil. (Eur J Esthet Dent 2008;3: ) 237 VOLUME 3 NUMBER 3 AUTUMN 2008

39 CLINICAL APPLICATION Puliction Introduction Ptients ffected severe dentl erosion often present with n extremely compromised dentition, especilly in the nterior mxillry qudrnt; the verticl dimension of occlusion my hve decresed, nd/or nd supreruption of the respective lveolr process segments my hve occurred. If erosion is not intercepted t n erly stge, full mouth rehilittion, mostly implementing conventionl full coverge (crowns), my e required. Thnks to improved dhesive techniques, the indictions crowns hve decresed nd more conservtive pproch my e proposed to preserve tooth structure, nd to postpone more invsive tretments until the ptient is older. A clinicl tril testing fully dhesive pproch is underwy t the School of Dentl Medicine t the University of Genev. All ptients ffected generlized dvnced dentl erosion re systemticlly nd exclusively treted with dhesive techniques, using onlys in the posterior region nd comintion of fcil onded porcelin restortions (BPRs) nd indirect pltl resin composite restortions in the nterior mxillry region. As the first nd the second steps of the concept hve een previously descried in detil, 1,2 this rticle focuses on the third nd lst step explining the rtionle ehind the pproch selected to restore the nterior mxillry qudrnt. For etter understnding, rief summry of the two previous steps is presented in the following prgrph. First step: mxillry vestiulr wxup nd the occlusl plne The first step of the three-step technique is designed to ensure the clinicin, the technicin nd the ptient gree on the finl tretment ojective outcome, ee ny irreversile therpy strts. The mjor gol is to vlidte the position selected the plne of occlusion of the finl restortions, which is in the uthors opinion the most frequently neglected prmeter in full-mouth rehilittion. During the first ppointment with the ptient, photogrphs, rdiogrphs nd lginte impressions re tken (s well s nmnesis nd comprehensive clinicl exmintion). Finlly, the visit is concluded with fceow record. The lortory technicin rticultes the two dignostic csts on semi-djustle rticultor the men of the fceow in the mximum intercusption position (MIP). As without the clinicl vlidtion of the position of the occlusl plne full-mouth wxup my e useless, the three-step technique proposes tht the technicin initilly wxes up only the vestiulr surfce of the mxillry teeth. At this time, neither the cingul of the nterior nor the pltl cusps of the posterior mxillry teeth should e included. Inspired the photogrphs of the ptient, the technicin concentrtes exclusively on the esthetic ppernce of the fcil surfces of the mxillry teeth, with mximum freedom of cretivity. An intermedite clinicl step is tken to verify tht the direction is correct, nd the dupliction of the mxillry vestiulr wxup the mens of precisely fitting silicone key concludes the first lortory step. 238 VOLUME 3 NUMBER 3 AUTUMN 2008

40 VAILATI/BELSER Tle 1 The three-step technique. Lortory Clinicl Puliction Mxillry vestiulr wxup Step 1: Esthetics Assessment of occlusl plne Posterior occlusl wxup Step 2: Posterior support Cretion of posterior occlusion t n incresed VDO Mxillry nterior pltl onlys Step 3: Anterior guidnce Reestlishment of finl nterior guidnce During the first clinicl step, the silicone key is loded with tooth-colored provisionl resin composite nd repositioned in the ptient s mouth. After its removl, ll the uccl surfces of the mxillry teeth re covered thin lyer of resin composite tht reproduces the defined shpe the future restortions (mxillry vestiulr mock-up). This fully reversile reconstruction of the vestiulr cusps of the mxillry posterior teeth nd the incisl edges of the nterior teeth llows perfect visuliztion of oth the plne of occlusion nd the overll esthetic ppernce of the future finl restortions. Other different dentl prmeters, such s the gingivl levels, re lso cliniclly ssessed with the full prticiption of the ptient, s descried in previous rticle. 1 Thnks to the mxillry vestiulr mockup, the ptient is ressured t n erly stge out the tretment ojective, which, in turn, normlly mens tht the ptient wishes to immeditely egin tretment. With the mock-up in plce, new photogrphs re tken, nd the technicin cn susequently progress to the second lortory step. Second step: posterior occlusl wxup nd new occlusion t n incresed verticl dimension of occlusion The second lortory step dels with the posterior occlusion, s t this stge, the wxup only involves the posterior qudrnts of oth the mxillry nd mndiulr csts. In cse of severely eroded dentition, n increse of the verticl dimension of occlusion (VDO) is inevitle in order to reduce the need sustntil tooth preprtion in generl nd to void the necessity of elective endodontic tretments in prticulr. For ech ptient, the new VDO is decided ritrrily on the rticultor, tking into considertion oth the posterior teeth, where the mximum fesile increse is desirle to mintin mximum of minerlized tissue, nd the nterior teeth, which should not e set too fr prt s this would jeoprdize the reestlishment of nterior interrch contcts nd the relted nterior guidnce. As the new VDO should 239 VOLUME 3 NUMBER 3 AUTUMN 2008

41 CLINICAL APPLICATION Puliction lwys e tested cliniclly prior to its finl cceptnce ee ny irreversile tretment strts, the second step is devoted to testing tht the ptient cn dpt to the new therpeutic occlusion. As explined in the uthors previous rticle 2, the lortory technicin will wx up only the two premolrs nd the first molr in ech sextnt to recrete the occlusl scheme plnned the finl restortions. 2 Four trnslucent silicone keys re then fricted, ech duplicting the wxup of one posterior qudrnt. The ptient is susequently scheduled next ppointment. This time the clinicin explins tht nother reversile tretment will e permed. However, this will chnge the occlusion of the ptient. The trnslucent keys re loded with resin composite prior to plcement in the ptient s mouth. Thnks to the descried trnslucency, light-curing resin composite cn e utilized. Without ny tooth preprtion (only etching nd onding), the occlusl surfce of ll the premolrs nd the first molrs re restored with lyer of resin composite, reproducing the respective dignostic wxup. The three-step technique recommends n ritrry oservtion period of pproximtely 1 month to ssess the ptient s dpttion to the newly estlished VDO. The new occlusion otined is peculir in tht the nterior teeth re no longer in contct. The degree of this trnsitionl open ite depends on the one hnd on the mount of increse of VDO required, nd on the other hnd on the ptient s originl verticl overlp nd the severity of the incisl edge destruction. Ptients should e inmed tht the esthetic ppernce of their smile could worsen t this trnsitionl stge of therpy, especilly in the cse of n extremely dmged nterior dentition. The worsening of their smile is due to the fct tht the mxillry posterior teeth hve een lengthened the posterior provisionl resin composites, wheres the mxillry incisl edges hve not yet een restored (Fig 1). Some speech impirments cn lso e expected, s the nterior teeth re set prt nd more ir cn escpe during the pronuncition of the letter s. However, ptients re generlly so motivted fter the first clinicl step tht they do not find this tretment phse prticulrly stressful or unerle. The second clinicl step hs een conceived to simplify the clinicin s work, without compromising the finl outcome of the full-mouth rehilittion. Consequently, it ws decided ll ptients not to ttempt to simultneously restore the nterior teeth while restoring the posterior qudrnt with provisionls. As previously mentioned, thnks to the mxillry mock-up of the first clinicl step, ptients re very trusting, s the plnned tretment ojective hs een visulized nd thoroughly explined eehnd. Consequently, this trnsitionl period is ccepted without mjor complints, nd none of the ptients enrolled in our study requested n erlier reconstruction of the nterior teeth. The most frequent ojection rised collegue clinicins to this technique is tht without dequte nterior guidnce, new occlusion t n incresed VDO cnnot e correctly ssessed. However, to dte, there is no roust scientific evidence ville to support this criticism. In the uthors experience, ptients re le to function well short period of time without nterior contcts. Finlly, ccording to the three-step technique, ll these ptients enrolled ther- 240 VOLUME 3 NUMBER 3 AUTUMN 2008

42 VAILATI/BELSER Puliction d e c f Fig 1 to f Three ptients ee tretment (left) nd t completion of the second clinicl step (right). As the nterior teeth hve not een restored t this stge ptients lose nterior guidnce nd the esthetic ppernce is worsened. The more compromised the nterior teeth re, the more visile the reverse smile will get. However, normlly, ptients do rect very well to this trnsitionl stge, s they undertook the mock-up session nd, thus, were ressured when it comes to the perspective of the plnned finl result of tretment. 241 VOLUME 3 NUMBER 3 AUTUMN 2008

43 CLINICAL APPLICATION Puliction py should undergo consulttion with specilist in the field of temporomndiulr disorders prior to inititing tretment, in order to ssess the clinicl sttus of their rticultions. As the second clinicl step (provisionl posterior resin composites) is considered fully reversile, the trnsient occlusl resin composite restortions cn e esily modified or completely removed from the unprepred posterior teeth if signs nd/or symptoms of temporomndiulr dysfunction should rise. Third step: the nterior guidnce At the completion of the second step, stle posterior occlusl support is estlished. As mentioned previously, owing to the presence of the posterior provisionl resin composites, the nterior teeth re set prt. Consequently, the third nd finl step of the three-step technique dels with the restortion of the nterior qudrnts (reestlishment of n dequte, functionl permnent nterior guidnce). Generlly, the pltl spect of the mxillry nterior teeth is severely ffected the destructive comintion of erosion nd ttrition, which leds to sustntil loss of tooth structure. After the loss of enmel, the exposed dentin is suject to ccelerted wer, which leds to pronounced concve morphology, nd frequently, to wekening nd frcturing of the incisl edges. Following the guidelines conventionl orl rehilittion concepts, such structurlly compromised teeth should receive full crown coverge. In order to plce the crown mrgins t the gingivl level, the entire coronl tooth structure, mesilly nd distlly, is removed to gurntee the pth of insertion of the crown (see Fig 2). The entire fcil spect will lso e sustntilly reduced in the process of prepring the 1.5 mm shoulder cermic mrgins porcelin-fused-to-metl crowns. Even when the more conservtive ll-cermic crowns re dopted (eventully <1mm of chmfer preprtion) the clinicin still hs to eliminte the mesil nd distl undercuts of the tooth nd smoothen the shrp edges, leding to highly invsive preprtion of the xil wlls. Severl studies hve demonstrted the importnce of the mrginl ridges posterior teeth. Restortions tht extend to the Restortion of the mxillry nterior teeth, minimlly invsive tretment: the sndwich pproch Fig 2 Mxillry incisors re chisel-shped teeth. In order to remove the retentive res nd to prepre mrgin of t lest 1 mm circumferentilly, crown preprtion cnnot e considered conservtive. Only veneer preprtion cn gurntee to preserve the tringulr shpe of these teeth, thnks to the fcil insertion pth of the restortion VOLUME 3 NUMBER 3 AUTUMN 2008

44 VAILATI/BELSER Puliction mesil nd distl spect, such s MOD restortion, gretly ffect the strength of the restored posterior teeth. 4-6 In the uthors opinion, the mesil nd distl mrginl ridges of the nterior teeth my hve similr importnce s descried posterior teeth in gurnteeing structurl strength, thus, representing frmework enmel. Theree, the removl of these mesil nd distl mrginl ridges of the nterior teeth could drmticlly compromise the tooth flexiility the ( tennis rcket theory ), see Fig 3. Prepring such teeth crowns will complete the destruction initited the erosive process. infrequently, elective endodontic tretment will e necessry, nd posts will then e used to ssure retention of the finl crowns. Only few rticles hve een pulished tht hve imed t investigting the survivl rte of single crowns on vitl nturl teeth, nd there re no long-term follow-up studies on the survivl of devitlized nd crowned teeth in very young ptients However, the prolems tht rise when tooth looses its vitlity, such us peripicl lesions, discolortions, root frctures, etc. re well documented To void ggressive tretments on the one hnd nd to keep teeth vitl on the other hnd, n experimentl pproch of restoring the mxillry nterior teeth of ptients ffected severe dentl erosion is currently under investigtion t the University of Genev, School of Dentl Medicine. The uthors minimlly invsive tretment concept consists of reconstructing the pltl spect with resin composite (direct or indirect, s will e explined lter in this rticle) nd to restore the fcil spect with cermic veneers. The finl outcome is reched the most conservtive pproch possile, s the remining tooth structure is preserved nd locted in the center etween two different restortions ( the sndwich pproch ) (Fig 4). Fig 3 Even though these teeth hve een severely structurlly compromised, the enmel lyer representing the reminder of the mesil nd distl mrginl ridges is still visile. Like the externl frme of tennis rcket, these nds of enmel my ply significnt role in strengthening the tooth ( the tennis rcket theory ). Fig 4 The sndwich pproch. Keeping tooth preprtion miniml, the remining tooth structure of the eroded mxillry nterior teeth is mintined in etween two dhesive restortions, permed t two different moments in time, i.e. first the pltl resin composite nd second the fcil cermic veneer. 243 VOLUME 3 NUMBER 3 AUTUMN 2008

45 CLINICAL APPLICATION Puliction Fig 5 At the completion of the second step, the ptient hs stle posterior occlusion. To reconstruct the pltl spect of the mxillry nterior teeth ee restoring them with veneers, the clinicin cn select direct or indirect resin composites. In this specific cse, indirect resin composite restortions were preferred, s it ws judged tht the interocclusl spce ws conspicuous nd tht the nterior guidnce could hve een etter recreted in the lortory. A still experimentl, ut highly promising, ultr-conservtive pproch, implementing oth sic principles of iomimetics nd dhesive technology, hs recently een pulished Mgne et l Severely compromised nterior teeth hve een restored without following the clssic rules of crown preprtion, which trditionlly would require locliztion of the restortion mrgins on sound tooth structure. To the contrry, teeth with extensive clss 3 defects were directly restored with dhesive resin composite restortions ee the fcil veneer preprtions were permed, treting the resin composite s n integrl prt of the tooth. In other terms, prt of the veneer mrgins were locted on resin composite. Along these lines the three-step technique hs pushed the limit of this innovtive ppliction, s the teeth to e restored with fcil cermic veneers hd previously the entire pltl surfce restored with resin composite. Such n ultr-conservtive pproch cnnot e mtched ny type of full-crown preprtion. For ll ptients involved in this prospective clinicl study, strict follow-up is scheduled to collect inmtion on the survivl nd eventully compliction rtes of such novel nterior restortions. The detiled protocol nd the preliminry results of the study will e the topic of nother rticle. Pltl spect: direct or indirect resin composites? After 1 month of functioning with the posterior occlusl interim resin composite restortions, it is ssessed whether or not the ptient feels comtle with the new occlusion. Susequently, two lginte impressions nd new fceow record re tken. In order to mount the csts in MIP, n nterior occlusl ite registrtion is lso required. The lortory technicin verifies on the mounted csts tht the second step hd een ccurtely executed. In other words, he/she must check tht the position of the occlusl plne is ctully locted where it ws plnned, nd tht the posterior teeth with the provisionl resin composites look similr to the originl wxup. Thnks to the presence of the non-restored second molrs, precise verifiction of the mount of increse of VDO is possile t ny time. The type of restortion tht is est indicted to restore the pltl spect of the mxillry nterior teeth (i.e. direct or indirect resin composite) is then selected, Fig 5. If the spce is reduced (<1mm), the resin composites cn e done directly free-hnd, sving time nd money (there 244 VOLUME 3 NUMBER 3 AUTUMN 2008

46 VAILATI/BELSER Puliction c Fig 6 to c Pltl only preprtion. The only tooth preprtion required is the slight opening of the interproximl contcts, to provide the lortory technicin ccess during trimming of the dyes on the mster cst. The dentin will e susequently clened, followed removing the most superficil lyer with dimond ur. e tht, due to the erosive process, cervicl chmfer-like preprtion is lredy present. is no lortory fee the pltl onlys nd only one clinicl ppointment is required). If the interocclusl distnce etween the nterior teeth is, insted, significnt, free-hnd resin composites could prove to e very chllenging. When the teeth present comintion of compromised pltl, incisl nd fcil spects, it is difficult to visulize the optiml finl morphology of the teeth, prticulrly while restoring t this stge only the pltl side with ruer dm in plce. Thus, the result my e unpredictle nd highly time consuming. Under such conditions, fricting the pltl onlys in the lortory clerly presents some dvntges, including superior wer resistnce nd higher precision during the cretion of the finl m. 24 Pltl onlys: tooth preprtion In cse the indirect pproch is selected, the clinicin will schedule n ppointment to proceed to the preprtion the pltl onlys of the six mxillry nterior teeth. This preprtion cn e quite n esy nd rpid procedure. In fct, in the cse of severe dentl erosion, the pltl spect of the mxillry nterior teeth is generlly the most ffected of the entire dentition. Under the descried circumstnces, the erosion nd the ttrition processes hve lredy creted the spce necessry the onlys, nd no dditionl tooth preprtion is required once n nterior tooth seprtion is generted the increse of VDO. In ddition, t closer oservtion, the cervicl prt next to the gingiv frequently, presents chmfer-like preprtion configurtion, with smll nd of enmel still present. Owing to the uffering ction of oth the sulculr fluid nd the plque, this thin lyer of enmel is often preserved from the cid ttck nd its presence will provide superior qulity of dhesion. As this chmfer is locted suprgingivlly nd there is no need to extend the mrgins sugingivlly, the next restortive steps re lso fcilitted (e.g. impression-tking nd onding of the finl restortions). 245 VOLUME 3 NUMBER 3 AUTUMN 2008

47 CLINICAL APPLICATION Puliction Fig 7 nd During the friction of the pltl resin composites, the technicin nd the clinicin cn decide to reestlish the full length of the future veneers or to keep the incisl edges slightly shorter. The only fetures required re to slightly open the interproximl contcts etween the mxillry nterior teeth mens of stripping nd to smoothen the incisl edges removing unsupported enmel prisms. The pltl dentin is lso clened with non-fluoride-contining pumice, nd the most superficil lyer removed with pproprite dimond urs (Fig 6). Owing to this miniml tooth preprtion, sensitivity does not develop. Consequently, no provisionl restortions re required during the time necessry the lortory technicin to fricte the pltl onlys. After the finl impression, the ppointment is concluded with n nterior ite registrtion of the ptient s mximum intercuspidtion position. Third lortory step: the friction of the pltl onlys The mxillry mster cst comprising the preprtions the pltl onlys is mounted on the rticultor in MIP. Another fceow record is not necessry t this stge, s the inmtion on how to orientte the csts to the hinge xis of the rticultor is preserved the previously mounted mndiulr cst. As the interproximl contcts hve een removed ee tking the impression, the mxillry nterior teeth re lredy slightly seprted from ech other on the working cst, fcilitting the trimming of the dyes. The lortory technicin is specificlly instructed to focus on the shpe of the pltl onlys in view of: 1. Estlishment of n dequte functionl nterior guidnce 2. Optimiztion of the future trnsition etween the pltl only nd the veneer. At this stge, the lortory technicin cn either directly fricte the pltl onlys, or decide to wx up completely the mxillry nterior teeth in order to etter visulize the future junction etween the pltl only nd its corresponding fcil veneer. This is demnding step, nd ech lortory technicin, who hs prticipted so fr in this project, hs selected slightly different pproch. 246 VOLUME 3 NUMBER 3 AUTUMN 2008

48 VAILATI/BELSER Puliction Fig 8 nd To fcilitte the positioning during onding of the pltl onlys, smll hook is fricted. This incisl stop will e removed esily during finishing nd polishing. e tht in this ptient the decision to restore the full length of the teeth with the pltl resin composites ws mde. During the friction of the pltl resin composites, the technicin nd the clinicin cn decide to reestlish the finl length of the future veneers or to keep the incisl edges slightly shorter (Fig 7). In cse of severe dentl erosion, the fcil spect of the mxillry teeth my lso e significntly involved nd the lyer of enmel thinned, to the point tht the teeth pper more yellow the dentin itself, exposed t the level of the incisl edges, could lso e stined. Consequently, ptients with dvnced dentl erosion frequently complin out the color of their teeth, ecoming victims like mny other people of the leching osession of modern times. If one hs decided to increse the length of the teeth ee the friction of the fcil veneers mens of the pltl onlys, ptients should e inmed tht there my e possile color mismtch with the vestiulr surfces. The color of the pltl onlys will e different, s it is ment to mtch the color of the finl veneers, insted of the unrestored fcil spect of the teeth. Generlly, ptients re so hppy to hve their nterior teeth lengthened tht they do not consider this s mjor drwck. It is very importnt tht the lortory technicin frictes kind of hook t the level of the incisl edge (incisl stop), mde of the sme mteril s the restortion, which will help to position nd stilize the only during the onding procedure (Fig 8). Third clinicl step: reestlishment of nterior contcts nd the nterior guidnce When n indirect pproch is selected, n dditionl ppointment is necessry to deliver the finl pltl restortions. Wheres tooth preprtion nd finl impression indirect pltl resin composites re simple procedures, onding of these restortions my e demnding step, not only the more difficult visiility of the operting field, ut ecuse of the necessity to gurntee moisture control. The posterior resin composites re provisionl restortions nd, thus, the use 247 VOLUME 3 NUMBER 3 AUTUMN 2008

49 CLINICAL APPLICATION Puliction Fig 9 Bonding procedure of pltl only. The use of ruer dm is crucil. To expose the mrgin it is necessry to plce clsp on the tooth receiving the only. Once the onding of the restortion completed, the clinicin will remove the clsp nd plce it on the djcent tooth to ond the next only. Fig 10 nd Third clinicl step. Clinicl close-up views ee nd fter onding of six pltl resin composite onlys. In this ptient, the full length of the future veneers ws reconstructed t this intermedite stge of therpy mens of pltl onlys. This pproch is clerly more demnding the lortory technicin, see Fig 7. Fig 11 nd Third clinicl step. Clinicl close-up views ee nd fter onding of six pltl resin composite onlys. In this ptient the resulting orofcil dimension of the restored teeth seems unnturlly lrger. This is due to the fct tht the teeth were not restored to their finl length t this stge in the tretment, see Fig VOLUME 3 NUMBER 3 AUTUMN 2008

50 VAILATI/BELSER Puliction Fig 12 At completion of the third step, the ptient is scheduled finl dignostic mock-up, which this time will involve only the six mxillry nterior teeth. The wxup of these teeth nd the susequent mock-up re necessry steps, not only to confirm the finl shpe of the veneers, ut lso to produce the silicone keys guiding the veneer preprtions nd serving s templte the provisionl restortions of ruer dm is not necessry, wheres the pltl onlys re finl restortions nd the onding conditions should e optiml. To ensure the est conditions the dhesive procedures, fter the plcement of ruer dm, every only is onded once t the time using hyrid resin composite (e.g. Miris, Coltène/Whledent), following the protocol proposed P. Mgne cermic veneers. The only difference is tht the intglio surfce of the resin composite pltl onlys is microsndlsted (30 µm Cojet snd, 3M Espe), nd not treted with fluoridic cid. To correctly isolte the mrgins, it is necessry to plce clsp on the tooth receiving the only, otherwise the ruer dm would overlp the mrgins (Fig 9). Considering tht the sustrte is mostly sclerotic dentin, nd tht the length of the finl restortions is sometimes doule of the originl length of the remining tooth structure, the tsk requested the onding is mjor. Success cn only e ensured optiml onding conditions on the one hnd nd the presence of enmel t ll mrgins of ech only, except, of course, t the incisl level. Once the tooth is isolted mens of ruer dm, the onding procedure itself is not complicted, s the incisl stops help to position the pltl onlys, the interproximl contct points re often not concern, nd the mrgins re suprgingivl (Figs 10 nd 11). Fcil spect: cermic veneers The restortion of the pltl spect of the mxillry nterior teeth concludes the three-step technique. At this stge, the ptient hs reched completely stle occlusl conditions (in the nterior nd posterior qudrnts) so the clinicin cn decide, without pressure, on the pce to dopt the completion of therpy nd on the type of restortions. Generlly, the mndiulr nterior teeth only need minor tretment nd cn, in most instnces, e restored with direct resin composites. Bee replcing the posterior provisionl resin composite restortions with cermic or resin composite onlys, it is preferle to complete the restortion of the fcil spect of the mxillry nterior teeth. 249 VOLUME 3 NUMBER 3 AUTUMN 2008

51 CLINICAL APPLICATION Puliction c Fig 13 to c Three silicone keys re otined from the wxup of the six nterior mxillry teeth: one the mock-up, nother the fcil reduction nd third one the incisl reduction. The index the mock-up will e used gin fter tooth preprtion of the veneers, to fricte the provisionl restortions. As the protocol followed t the University of Genev previews fcil cermic veneers to e the permnent restortions, second mock-up of the six mxillry nterior teeth is recommended (Fig 12). While wxing up, the technicin should e guided the mxillry vestiulr mock-up done t the eginning of the three-step technique, nd dpt it to the new occlusion of the ptient. As the position of the occlusl plne nd the increse of VDO my e slightly different from wht ws initilly plnned, the length of the mxillry nterior teeth should e reconfirmed during the second mock-up session. If the ptient s consensus on the finl shpe of the mxillry nterior teeth is otined, nother two silicone indexes re fricted sed on the wxup, to guide the clinicin during veneer preprtion (reduction keys) (see Fig 13) The veneer preprtion follows stndrd protocols developed nd descried in detil other uthors (Fig 14) The only difference etween this novel concept nd more trditionl veneer pproch is tht the pltl spects of the mxillry nterior teeth re considered s integrl prt of the respective teeth nd no prticulr eft is mde to plce the preprtion mrgins the veneers on tooth structure. In ddition, the 250 VOLUME 3 NUMBER 3 AUTUMN 2008

52 VAILATI/BELSER Puliction Fig 14 to c Initil clinicl view of 27-yer-old mle ptient ee nd fter onding of six mxillry nterior cermic veneers. e oth the gingivl helth nd the miniml tooth preprtion. The rehilittion hs een permed ccording to the principles of the three-step concept. The next step will involve the replcement of the posterior provisionl resin composites. c Fig 15 nd Two different typicl clinicl situtions during the onding procedure of the fcil veneers. e tht in Fig 15 the fcil enmel hs een preserved. However, in Fig 15 the erosive process hd gretly ffected the fcil spect of the tooth. 251 VOLUME 3 NUMBER 3 AUTUMN 2008

53 CLINICAL APPLICATION Puliction Fig 16 Schemtic drwing of the recommended preprtion the veneers t the level of the incisl edges. The length dded the pltl only is completely removed. The cermic veneer will lter reestlish the finl length. c Fig 17 to c Three different ptients fter veneer preprtion with the silicone key in plce reproducing the length of the finl veneers. Following the protocol of the University of Genev, ll the tooth-length dded the pltl resin composites hd to e removed. 252 VOLUME 3 NUMBER 3 AUTUMN 2008

54 VAILATI/BELSER Puliction descried concept comprises n incisl coverge in m of utt joint, with the cermic veneer mrgin plced in the volume of the pltl resin composite onlys (see Fig 15). 32 In sitution where the incisl length of the mxillry nterior teeth is severely reduced nd the respective tooth volume hs een susequently reestlished mens of pltl onlys, the decision hs to e mde whether or not to remove the entire length dded with the resin composite or to leve prt of it ee restoring the teeth with the fcil veneers. The uthors preference is to completely remove the length dded the pltl onlys, leving only the originl length of the tooth on the fcil spect (Fig 16). The rtionle this pproch is to void plcing the mrgin of the veneers in the pltl concvity of the tooth, moving it more cerviclly (Fig 15). 33 In ddition, without the lyer of resin composite, the veneer friction is fcilitted, s there is more unim color on the fcil surfce. Even in ptients where lmost three qurters of the originl tooth length is missing, the guidelines preview not to preserve some of the length of the pltl only (Figs 16 nd 17). As the sndwich pproch is still experimentl, strict follow up of ll these types of restortions is pplied. By mens of photos nd impressions the interfce etween the fcil veneers nd the pltl resin composite onlys is crefully evluted. Time will show Fig 18 to c The two yer follow-up of ptient treted following the sndwich pproch the mxillry nterior teeth demonstrted very encourging results. The gingivl helth is remrkle, nd ll the teeth re still vitl. c 253 VOLUME 3 NUMBER 3 AUTUMN 2008

55 CLINICAL APPLICATION Puliction if prolems my rise. However, the initil dt collected seemed very promising (Fig 18). After onding of the mxillry nterior veneers, the rehilittion cn progress with the replcement of the posterior provisionl resin composites. In fct, owing to the presence of functionl nterior guidnce nd optimized posterior support, the full-mouth rehilittion cn e, from this point on, plnned ccording to qudrnt-wise pproch, which simplifies the therpy oth ptient nd clinicin. Bsed on individul, ptient-relted criteri, the clinicin nd the technicin cn decide t which qudrnt to strt. Furthermore, hving the plne of occlusion estlished with provisionl restortions still llows minor modifictions to e mde. The vestiulr cusps of the posterior provisionl resin composites could e lengthened dding new resin composite, or shortened grinding. One of the mjor dvntges of the three-step technique consists of the fct tht the opportunity to mke modifictions is mintined throughout the different tretment phses. Under such conditions it is not surprise tht the finl esthetic outcome of this kind of full-mouth rehilittion is consistently plesing (Fig 19). Conclusions Dentl erosion is frequently underestimted pthology, which ffects n incresing numer of younger individuls Often the dvnced tooth destruction is the result, not only of difficult initil dignosis (e.g. multifctoril etiology of tooth wer), ut lso of the lck of timely intervention. Trditionlly, extensive dentl therpies re previewed these ptients, nd clinicins often prefer to wit until the tooth tissue loss is more conspicuous ee proposing conventionl full-mouth rehilittion. This hesittion founds its rtionle in the ggressiveness of the conventionl therpies. Owing to the descried novel nd highly conservtive pproch, the University of Genev, School of Dentl Medicine hs ecome one of the centers of reference ptients ffected dvnced dentl erosion. In the pst few yers, numer of ptients suffering from severely eroded dentitions hve een treted ccording to this still experimentl pproch, which siclly fetures miniml tooth preprtion nd mintennce of tooth vitlity. The new clinicl pproch (full-mouth dhesive rehilittion) the tretment of dvnced generlized erosion, consists exclusively of posterior onlys nd nterior BPRs, nd is strtegiclly plnned in wy tht llows rehilitting ptients qudrnt-wise, insted of restoring oth dentl rches simultneously Even though dhesive techniques simplify oth the clinicl nd the lortory procedures, restoring such compromised dentitions still remins chllenge due to the often dvnced mount of tooth destruction. To chieve mximum preservtion of tooth structure nd the most predictle esthetic nd functionl outcome, n innovtive concept hs een developed: the three-step technique. Three lortory steps re lternted with three clinicl steps, llowing the clinicin nd the dentl technicin to constntly interct during the plnning nd execution of full-mouth dhesive rehilittion. 254 VOLUME 3 NUMBER 3 AUTUMN 2008

56 VAILATI/BELSER Puliction In this rticle, the uthors descrie the third nd lst step of the three-step technique in detil. To reduce the risk of mechnicl overlod on the onded restortions, ptients who present prfunctionl hits were not included in this clinicl tril. How c d Fig 19 to d 29-yer old ptient t completion of the dhesive rehilittion. Thnks to the three-step technique, the occlusl plne nd the incisl edge position re in hrmony, s this ws determined during the first step mxillry vestiulr mock-up nd continuously improved minor modifictions long the tretment. ever, the incresed demnd tretment hs led to eliminting this exclusion criterion. The next chllenge will e to tret this popultion of ptients nd to document the long-term survivl rte of their full-mouth dhesive rehilittion. 255 VOLUME 3 NUMBER 3 AUTUMN 2008

57 CLINICAL APPLICATION Puliction Acknowledgements Treting the descried complex cses is tem eft. Consequently, the uthors would like to thnk ll the lortory technicins nd clinicins who hve contriuted to the finl outcome of the different full-mouth rehilittions, the lortory technicins nd cermists: Alwin Schönenerger, Ptrick Schnider, Serge Erpen nd Sylvin Crciofo their meticulous execution of the lortory work. Dr Giovnn Vglio, Dr Federico Prndo nd Dr Tommso Rocc their enthusistic collortion nd excellent clinicl work, nd finlly Dr Olivier Mrmy his expertise during the temporomndiulr consulttions. References 1. Vilti F, Belser UC. Full-mouth dhesive rehilittion of severely eroded dentition: the three-step technique. Prt I. Eur J Esth Dent 2008;3: Vilti F, Belser UC. Full-mouth dhesive rehilittion of severely eroded dentition: the three-step technique. Prt II. Eur J Esth Dent 2008;3: Mgne P, Belser UC. Bonded porcelin restortions in the nterior dentition. A iomimetic pproch. Chicgo: Pulishing Co 2002; Pnitvisi P, Messer HH. Cuspl deflection in molrs in reltion to endodontic nd restortive procedures. J Endod 1995;21: Reeh ES, Messer HH, Dougls WH. Reduction in tooth stiffness s result of endodontic nd restortive procedures. J Endod 1989;15: Reeh ES, Dougls WH, Messer HH. Stiffness of endodonticlly treted teeth relted to restortion technique. J Dent Res 1989;68: Pjetursson BE, Siler I, Zwhlen M, Hämmerle CH. A systemtic review of the survivl nd compliction rtes of ll-cermic nd metl-cermic reconstructions fter n oservtion period of t lest 3 yers. Prt I: Single crowns. Clin Orl Implnts Res 2007;18: Siler I, Pjetursson BE, Zwhlen M, Hämmerle CH. A systemtic review of the survivl nd compliction rtes of ll-cermic nd metl-cermic reconstructions fter n oservtion period of t lest 3 yers. Prt II: Fixed dentl prostheses. Clin Orl Implnts Res 2007;18(Suppl 3): Vn Nieuwenhuysen JP, D Hoore W, Crvlho J, Qvist V. Long-term evlution of extensive restortions in permnent teeth. J Dent 2003;31: Wlton TR. An up to 15-yer longitudinl study of 515 metlcermic FPDs: Prt 2. Modes of filure nd influence of vrious clinicl chrcteristics. Int J Prosthodont 2003;16: Wlton TR. A 10-yer longitudinl study of fixed prosthodontics: clinicl chrcteristics nd outcome of single-unit metlcermic crowns. Int J Prosthodont 1999;12: Vlderhug J, Jokstd A, Amjornsen E, Norheim PW. Assessment of the peripicl nd clinicl sttus of crowned teeth over 25 yers. J Dent 1997;25: Wlton JN, Grdner FM, Agr JR. A survey of crown nd fixed prtil denture filures: length of service nd resons replcement. J Prosthet Dent 1986;56: Coornert J, Adriens P, De Boever J. Long-term clinicl study of porcelin-fused-togold restortions. J Prosthet Dent 1984;51: Tn K, Pjetursson BE, Lng NP, Chn ES. A systemtic review of the survivl nd compliction rtes of fixed prtil dentures (FPDs) fter n oservtion period of t lest 5 yers. Clin Orl Implnts Res 2004;15: Aquilino SA, Cpln DJ. Reltionship etween crown plcement nd the survivl of endodonticlly treted teeth. J Prosthet Dent 2002;87: Schwrtz NL, Whitsett LD, Berry TG, Stewrt JL. Unservicele crowns nd fixed prtil dentures: life-spn nd cuses loss of serviceility. J Am Dent Assoc 1970;81: Pul JE. Pltl inlys. Br Dent J 1994;177: Bishop K, Briggs P, Kelleher M. Pltl inlys. Br Dent J 1994;177: Mgne P, Dougls WH. Interdentl design of porcelin veneers in the presence of composite fillings: finite element nlysis of composite shrinkge nd therml stresses. Int J Prosthodont 2000;13: VOLUME 3 NUMBER 3 AUTUMN 2008

58 VAILATI/BELSER Puliction 21. Mgne P, Dougls WH. Cumultive effects of successive restortive procedures on nterior crown flexure: intct versus veneered incisors. Int 2000;31: Mgne P, Dougls WH. Porcelin veneers: dentin onding optimiztion nd iomimetic recovery of the crown. Int J Prosthodont 1999;12: Mgne P, Dougls WH. Optimiztion of resilience nd stress distriution in porcelin veneers the tretment of crown-frctured incisors. Int J Periodontics Restortive Dent 1999;19: Dietschi D, Sprefico R. Adhesive metl-free restortions. Berlin:, Mgne P, Belser UC. Novel porcelin lminte preprtion pproch driven dignostic mock-up. J Esthet Restor Dent 2004;16: Gürel G. The science nd rt of porcelin lminte veneers. Chicgo: Pulishing, Mgne P, Perroud R, Hodges JS, Belser UC. Clinicl permnce of novel-design porcelin veneers the recovery of coronl volume nd length. Int J Periodontics Restortive Dent 2000;20: Mgne P, Dougls WH. Porcelin veneers: dentin onding optimiztion nd iomimetic recovery of the crown. Int J Prosthodont 1999;12: Mgne P, Dougls WH. Additive contour of porcelin veneers: key element in enmel preservtion, dhesion, nd esthetics ging dentition. J Adhes Dent 1999;1: Belser UC, Mgne P, Mgne M. Cermic lminte veneers: continuous evolution of indictions. J Esthet Dent 1997;9: Grer D. Porcelin lminte veneers: ten yers lter. Prt I: Tooth preprtion. J Esthet Dent 1993;5: Cstelnuovo J, Tjn AH, Phillips K, Nicholls JI, Kois JC. Frcture lod nd mode of filure of cermic veneers with different preprtions. J Prosthet Dent 2000;83: Mgne P, Belser UC. Bonded porcelin restortions in the nterior dentition. A iomimetic pproch. Chicgo: Pulishing Co, 2002; Deery C, Wgner ML, Longottom C, Simon R, Nugent ZJ. The prevlence of dentl erosion in United Sttes nd United Kingdom smple of dolescents. Peditr Dent 2000;22: Linnett V, Seow WK. Dentl erosion in children: literture review. Peditr Dent 2001;23: VOLUME 3 NUMBER 3 AUTUMN 2008

59 ACE Clss I Thinning of pltl enmel Tretment: No restortive tretment ACE Clss II Dentin exposure on the pltl spect (contct res), no dmge to incisl edges Tretment: Direct or indirect pltl composites ACE Clss III 2 mm Dentin exposure on the pltl spect, dmge to incisl edges (< 2 mm) Tretment: Pltl veneers ACE Clss IV 2 mm Extended dentin exposure on the pltl spect, loss of tooth length (> 2 mm), preserved fcil enmel Tretment: Sndwich pproch ACE Clss V Extended dentin exposure on the pltl spect, loss of tooth length (> 2 mm), loss of fcil enmel Tretment: Sndwich pproch (experimentl) ACE Clss VI Advnced loss of tooth structure leding to pulp necrosis Tretment: Sndwich pproch (highly experimentl) The Interntionl Journl of Periodontics & Restortive Dentistry 2010 BY QUINTESSENCE PUBLISHING CO, INC. PRINTING OF THIS DOCUMENT IS RESTRICTED TO PERSONAL USE ONLY. NO PART OF THIS ARTICLE MAY BE REPRODUCED OR TRANSMITTED IN ANY FORM WITHOUT WRITTEN PERMISSION FROM THE PUBLISHER.

60 559 Clssifiction nd Tretment of the Anterior Mxillry Dentition Affected Dentl Erosion: The ACE Clssifiction Frncesc Vilti, MD, DMD, MSc* Urs Christoph Belser, DMD, Prof Dr Med Dent** Erosive tooth wer is serious prolem with very costly consequences. Intercepting ptients t the initil stges of the disese is criticl to void significnt irreversile dmges to their dentition nd to enefit from still fvorle conditions when it comes to clinicl permnce of the restortive mesures proposed. In this rticle, new clssifiction is proposed to quntify the severity of the dentl destruction nd to guide clinicins nd ptients in the therpeutic decision-mking process. The clssifiction is sed on severl prmeters relevnt oth the selection of tretment nd the ssessment of the prognosis, such s dentin exposure in the pltl tooth contct res, ltertions t the level of the incisl edges, nd ultimtely, loss of pulp vitlity. (Int J Periodontics Restortive Dent 2010;30: ) *Senior Lecturer, Deprtment of Fixed Prosthodontics nd Occlusion, School of Dentl Medicine, University of Genev, Genev, Switzerlnd; Privte Prctice, Genev, Switzerlnd. **Chirmn, Deprtment of Fixed Prosthodontics nd Occlusion, School of Dentl Medicine, University of Genev, Genev, Switzerlnd. Correspondence to: Dr Frncesc Vilti, rue Brthélemy-Menn 19, Genev, Switzerlnd 1205; emil: frncesc.vilti@unige.ch. In modern society, dentl erosion hs ecome one of the mjor cuses of the loss of minerlized tooth structure. Severl surveys hve pointed out high nd still incresing prevlence, especilly mong young individuls (eg, 37% of 14-yer-olds in the United Kingdom present signs of pltl enmel erosion) Signs of dentl erosion tht my e esily evident t n erly stge include: glossy (smooth, glzed) enmel, yellowing of the teeth from the underlying dentin, incresed incisl trnslucency, nd cupping of the occlusl surfces. While the presence of dentl cries normlly leds clinicins to tke ction immeditely, in the cse of dentl erosion, mny clinicins prefer to postpone ny dentl tretment until the ptient is older, even though literture confirms tht direct clinicl oservtion is n unrelile method monitoring the rtes of tooth wer. 13,14 To ply down this prolem is frequently the preferred pproch, which is understndle since mny clinicins do not feel comtle proposing n extensive dentl rehilittion to young individuls who re still symptomtic nd unwre of Volume 30, Numer 6, BY QUINTESSENCE PUBLISHING CO, INC. PRINTING OF THIS DOCUMENT IS RESTRICTED TO PERSONAL USE ONLY. NO PART OF THIS ARTICLE MAY BE REPRODUCED OR TRANSMITTED IN ANY FORM WITHOUT WRITTEN PERMISSION FROM THE PUBLISHER.

61 560 the prolem. Wht such clinicins re not considering, however, is tht these ptients sooner or lter will need to restore their jeoprdized dentition nywy. The dete over whether it is preferle to strt erlier with lighter, less invsive rehilittion or lter with highly ggressive ut eventully more resistnt one is still open. The im of this rticle is to convince clinicins tht in the specific cse of dentl erosion, hesittion in undertking the dequte tretment will inevitly led to further degrdtion of the ptient s dentition. To persude the ptients nd to otin inmed consent tretment, it is necessry to quntify the dentl destruction nd to mke prognosis on the future progression of the disese if no tretment would e undertken. It would pper tht the existing erosion ssessment indices nd clssifictions hve not led to rod respective wreness mong dentl cre providers to dte. This my e ecuse these tools re rther complex nd difficult to use in dily prctice set-up, since they hve een primrily designed scientific purposes. Furthermore, prcticl experience indictes tht ll relevnt signs linked to the vrious progression stges of generlized dentl erosion could e ssessed cliniclly minly exmining the nterior dentition. This finding my help to simplify the dignostic process significntly. Consequently, new clssifiction, the nterior clinicl erosive clssifiction (ACE), hs een proposed to provide clinicins with prcticl tool to grde the dentl sttus of ech ptient nd to susequently relte it to the pproprite tretment. Mxillry nterior teeth nd dentl erosion Disese progression In the cse of dentl erosion, the pltl spect of the mxillry nterior teeth usully ppers to e the most ffected portion of the dentition, prticulrly in ptients with n intrinsic etiology (eg, gstric reflux, psychitric diseses). At n erly stge, cid-cused destruction cn e very sutle nd thus difficult to discover ecuse of the somewht hidden loction of the pltl tooth surfces, especilly if the disese progresses slowly. Ptients frequently do not present signs of tooth sensitivity, even in the presence of dentin exposure. Often, the erosive wer will mnifest too lte, when irreversile dmge hs lredy tken plce nd costly restortive tretments re required. At the initil stge, only n ttentive nd trined eye cn detect the more yellowish color resulting from the thinning of the enmel in the centrl pltl portion of the clinicl crown. The cingul pper fltter nd their surfces re very shiny. The next step of erosive wer leds to wekening of the incisl edges, which is first noticele n increse in trnslucency. Furthermore, the presence of cries or Clss III restortions my contriute dditionlly to the wekening of the fcil spect of the tooth. In extreme instnces, complete loss of the incisl edge my result, which depends strongly on the originl overite nd overjet configurtion nd on the loction of the occlusl contct re. For exmple, in ptient with slight verticl overlp (overite), the risk of incisl frcture is very high ecuse of the destructive comintion of erosion nd the focl ttrition of the ntgonist teeth. In fct, t n erly stge of enmel erosion, chipping is frequently visile in the m of irregulrities t the incisl edges. On the other hnd, in ptients with deep ite interrch configurtion, the mxillry nterior teeth my present pronounced concve morphology on their pltl spect ee ny effect on the length of the clinicl crown mnifests. In extreme situtions, the loss of the tooth structure my ecome so extensive tht the pulp chmer (or its originl extent) cn e identified on the pltl spect. Surprisingly, such teeth frequently keep their vitlity; however, they my respond less quickly to the vitlity test. In dvnced stges, when the lil tooth structure hs een undermined too much, the fcil surfces frcture nd the clinicl crowns suddenly pper reduced in length. Finlly, especilly in deep ite ptients, the verticl overlp my e ggrvted the supreruption of the nterior segments. Trditionl reconstructive versus dhesive therpy Following the guidelines conventionl orl rehilittion concepts, structurlly compromised teeth The Interntionl Journl of Periodontics & Restortive Dentistry 2010 BY QUINTESSENCE PUBLISHING CO, INC. PRINTING OF THIS DOCUMENT IS RESTRICTED TO PERSONAL USE ONLY. NO PART OF THIS ARTICLE MAY BE REPRODUCED OR TRANSMITTED IN ANY FORM WITHOUT WRITTEN PERMISSION FROM THE PUBLISHER.

62 561 should receive complete crown coverge. To plce the ssocited restortion mrgins t the gingivl level, significnt mount of the remining volume of the clinicl crown hs to e removed during tooth preprtion to provide the required verticl pth of insertion the crown. In other terms, prepring such teeth crowns will sustntilly ggrvte the destruction of minerlized tissue tht ws initited the erosive process. infrequently, elective endodontic tretment will e necessry, mostly ccompnied the use of posts, to ssure intrrdiculr retention of the crowns to e cemented. To void these types of invsive tretment modlities nd to keep the teeth vitl, n experimentl pproch to restoring the mxillry nterior teeth of ptients ffected severe dentl erosion is currently under investigtion t the University of Genev School of Dentl Medicine (Genev Erosion study) the uthors of this reserch. A minimlly invsive tretment concept tht consists of reconstructing the pltl spect with composite restortions, followed the restortion of the fcil spect with cermic veneers, is promoted. The tretment ojective is reched the most conservtive pproch possile, since the remining tooth structure is preserved nd locted in the center etween two different restortions (the sndwich pproch) nd permed t two different time points. When it comes to the preservtion of minerlized tooth structure, such n ultrconservtive pproch cnnot e mtched ny type of complete crown coverge. The type of restortion est indicted to restore the pltl spect of the eroded mxillry nterior teeth (direct or indirect composite restortions) is selected ccording to the mount of the nterior interocclusl spce otined fter n increse in the verticl dimension of occlusion. If the spce is limited (< 1 mm), the composite restortions cn e fricted free-hnd, sving time nd money (there is no lortory fee the pltl onlys nd only one clinicl ppointment is required). If the interocclusl distnce etween the nterior teeth is significnt, however, free-hnd resin composites could prove to e rther chllenging. When the teeth present comintion of compromised pltl, incisl, nd fcil spects, it is difficult to visulize the optiml finl morphology of the teeth, prticulrly while restoring only the pltl spect with ruer dm in plce. Thus, the results my e unpredictle nd highly time consuming. Under such conditions, fricting pltl onlys in lortory clerly presents some dvntges, including superior wer resistnce nd higher precision during friction of the definitive m. A series of rticles on full-mouth dhesive rehilittion ddress this in detil One of the criticisms to the sndwich pproch is the work nd cost ssocited with the friction of two seprte restortions ech tooth. However, only with two independent restortions re two different pths of insertion possile, nd the tooth preprtion cn theree e kept miniml. Even the most conservtive preprtion ll-cermic crowns could not chieve this level of tooth preservtion. ACE clssifiction Assessment of the severity of dentl erosion is complicted ecuse of the sujectivity of the methods of evlution nd the possile presence of wer cofctors (prfunctionl hits, hyposlivtion, wer resulting from tooth mlposition, ging, corse diet, inpproprite tooth-rushing techniques, rsive toothpstes, etc). In ddition, the rting scles selected investigtors my e somewht complicted to trnslte in clinicl environment, nd erly ltertions re difficult to locte, even with the support of photogrphy, study csts, nd ttentive clinicl exmintion Severl uthors hve proposed clssifictions nd indices ddressing either tooth wer in generl 25 or including dignostic criteri erosive tooth wer specificlly. 26 Most recently, Brtlett et l 18 pulished new scoring system, termed sic erosive wer exmintion (BEWE), designed oth scientific nd clinicl purposes. It ws the uthors twofold ojective to provide simple tool use in generl prctice nd to permit more scientificlly oriented comprisons with lredy existing indices. Furthermore, the BEWE imed to ugment the wreness of tooth erosion mong generl prctitioners nd to provide respective guide tretment when indicted. Finlly, the BEWE ws intended to stop the continued prolifertion of new indices, s Volume 30, Numer 6, BY QUINTESSENCE PUBLISHING CO, INC. PRINTING OF THIS DOCUMENT IS RESTRICTED TO PERSONAL USE ONLY. NO PART OF THIS ARTICLE MAY BE REPRODUCED OR TRANSMITTED IN ANY FORM WITHOUT WRITTEN PERMISSION FROM THE PUBLISHER.

63 562 Tle 1 The ACE clssifiction Pltl Pltl Incisl edge Fcil Pulp Suggested enmel dentin length enmel vitlity therpy Clss I Reduced exposed Preserved Preserved Preserved No restortive tretment Clss II Lost in contct Minimlly exposed Preserved Preserved Preserved Pltl composites res Clss III Lost Distinctly exposed Lost 2 mm Preserved Preserved Pltl onlys Clss IV Lost Extensively exposed Lost > 2 mm Preserved Preserved Sndwich pproch Clss V Lost Extensively exposed Lost > 2 mm Distinctively Preserved Sndwich pproch reduced/lost (experimentl) Clss VI Lost Extensively exposed Lost > 2 mm Lost Lost Sndwich pproch (highly experimentl) Fig 1 ACE Clss I: (left) Frontl nd (right) occlusl views. Very erly detection of the erosive prolem. All the cingul lost their microntomicl detils. The enmel ppers very shiny. Even though there is not yet dentin exposure, smll chipping of the enmel t the incisl edge is visile (miniml verticl overlp). Considering the ptient s ge (25 yers) nd etiology (ulimi), this ptient hs high risk of deteriorting towrd more severe stge in short period of time. it ws hoped to represent consensus within the specilized scientific community. Nevertheless, there is still n undisputle need clssifiction tht directly nd specificlly focuses on the nterior mxillry dentition, where loss of minerlized tissue ecuse of erosion, s minute s it my e t n erly stge of the disese, cn e ssessed esily. Clinicins not involved in epidemiologic surveys clerly need the lest complicted pproch to clssify ech ptient rpidly nd to decide on the most pproprite tretment pln. Thus, the prerequisite precise nd rpid ssessment is dignostic instrument tht is sed on limited numer of key prmeters nd tht guides the clinicin in logicl nd systemtic wy. As consequence, these two fundmentl prdigms hve een instrumentl in the development nd finliztion of the proposed ACE clssifiction (Tle 1). The ACE clssifiction is strictly relted to the clinicl oservtion of the sttus of the nterior mxillry teeth, which re generlly the most dmged. Ptients re grouped into six clsses, nd ech clss, dentl tretment pln is suggested. The clssifiction is sed on five prmeters relevnt the selection of the tretment nd the ssessment of the prognosis: the dentin exposure in the contct res, the preservtion of the incisl edges, the length of the remining clinicl crown, the presence of enmel on the vestiulr surfces, nd the pulp vitlity. ACE Clss I: Flttened cingul without dentin exposure Suggested therpy: No restortive tretment This is the erliest stge of dentl erosion. The enmel is present ut thinner. The pltl spect of the teeth my pper more yellowish in the centrl portion of the underlying dentin nd more white t the periphery with the presence of thicker enmel (Fig 1). The Interntionl Journl of Periodontics & Restortive Dentistry 2010 BY QUINTESSENCE PUBLISHING CO, INC. PRINTING OF THIS DOCUMENT IS RESTRICTED TO PERSONAL USE ONLY. NO PART OF THIS ARTICLE MAY BE REPRODUCED OR TRANSMITTED IN ANY FORM WITHOUT WRITTEN PERMISSION FROM THE PUBLISHER.

64 563 Fig 2 ACE Clss II: Pretretment (left) frontl nd (center) occlusl views nd (right) posttretment occlusl view. In this ptient, the pltl spects present res of dentin exposure t the level of the contct points. The incisl edges were still intct. An erly conservtive rehilittion ws plnned, nd ll mxillry nterior teeth were restored using n indirect pproch (pltl veneers), while the posterior teeth received direct composite restortions. For ptients in this ctegory, no restortive tretment is recommended. However, preventive mesures (eg, occlusl gurd, fluoride gel) re mndtory. Most of ll, the etiology should e investigted nd the cuse of the dentl erosion eliminted. Since the enmel lyer is still intct, 100% recovery is possile t this stge if the ptient is cple of preventing further tissue loss. ACE Clss II: Dentin exposure on the pltl spect (contct res), no dmge to the incisl edges Suggested therpy: Direct or indirect pltl onlys In this group of ptients, the enmel t the level of the pltl spect of the mxillry teeth is more compromised nd smll res of dentin re exposed, generlly relted to the contct points of the opposing dentition (Fig 2). Since the mndiulr nterior teeth re rrely ffected erosion, their incisl edges, composed of enmel, typiclly remin intct nd ct like chisels, dmging the mxillry nterior teeth in very ggressive mnner (focl ttrition). Since the occlusl contcts re now composed of softer dentin, it is resonle to nticipte tht the loss of tooth structure will worsen t fster rte, especilly if the cuse of the erosion is not under control. This is the reson why the dentl sttus of ptients ffected dentl erosion my deteriorte quickly fter n initil slow strt (Fig 3). Noody cn predict exctly how ech ptient will evolve; nevertheless, prmeters such s ge nd etiology of the dentl erosion cn guide the clinicin to predict the steepness of the curve of the disese progression nd to justify erly intervention. A ulimic ptient in his or her erly 20s who lredy presents exposed res of dentin (Clss II) is t higher risk of deteriorting the dentition compred to ptient in his or her 50s who suffers from gstric reflux tht is kept under medicl control. The first ptient should e treted immeditely, even though severl uthors recommend controlling the disese first Volume 30, Numer 6, BY QUINTESSENCE PUBLISHING CO, INC. PRINTING OF THIS DOCUMENT IS RESTRICTED TO PERSONAL USE ONLY. NO PART OF THIS ARTICLE MAY BE REPRODUCED OR TRANSMITTED IN ANY FORM WITHOUT WRITTEN PERMISSION FROM THE PUBLISHER.

65 564 Tooth structure Enmel Coronl dentin Rdiculr dentin Adhesive therpy, ACE Clss II ptient Adhesive therpy, ACE Clss III ptient Adhesive therpy, ACE Clss IV ptient Loss of tooth vitlity No restortive tretment Conventionl therpy Fig 3 Correltion etween loss of tooth structure nd the ptient s ge in cses of dentl erosion. The chnge in the steepness of the curve is relted to the loss of enmel nd the consequent dentin exposure in the contct res. Severl fctors cn dd to the ggrvtion of the steepness of the curve (prfunctionl hits, hyposlivtion, lck of erosion control, cidic diet, etc) Age (y) Since psychologic prolem is not often resolved quickly, protecting the remining enmel nd the exposed dentin from further dmge is recommended, even though the restortions my hve less fvorle prognosis under these specific conditions In the opinion of the uthors of this pper, the pltl spect of Clss II ptients should e restored s soon s possile, either mens of direct or indirect composite restortions (erly not invsive rehilittion). If the pltl wer hs not yet ffected the strength of the incisl edges nd the length of the fcil surfces of the teeth is still intct, restortion of the pltl spect of the mxillry nterior teeth could e the only tretment required. To otin the necessry interocclusl spce, djunctive orthodontic tretment could e dvocted, which llows the posterior teeth to e excluded from the tretment. However, not every ptient ccepts this possiility. A second option to otin the nterior spce needed consists of incresing the ptient s verticl dimension of occlusion. In this cse, ll the posterior teeth, t lest in one rch, re restored with direct composite restortions without ny tooth preprtion. Since the dentl destruction is intercepted t n erly stge, there is not enough spce thicker, indirect posterior restortions; removing tooth structure to crete the spce thicker restortions goes ginst the principles of miniml invsiveness. This erly nd extensive rehilittion sed on direct composites is not well ccepted mong clinicins, who think tht restoring so mny teeth with so-clled wek restortions is n overtretment which sufficient longevity would not e gurnteed. As consequence, mny clinicins prefer to wit until further dmge hs tken plce to justify full-mouth rehilittion sed on stronger restortions (onlys or crowns). Untuntely, there re no clinicl studies ville to dte showing which choice my e the most eneficil in the long term to ACE Clss II ptients: n immedite rehilittion with weker direct composites nd no tooth preprtion, or lter tretment with more resistnt restortions ut more compromised dentition nd more ggressive tooth preprtion. Thus, further clinicl reserch is needed. In the current investigtion eing undertken the uthors of The Interntionl Journl of Periodontics & Restortive Dentistry 2010 BY QUINTESSENCE PUBLISHING CO, INC. PRINTING OF THIS DOCUMENT IS RESTRICTED TO PERSONAL USE ONLY. NO PART OF THIS ARTICLE MAY BE REPRODUCED OR TRANSMITTED IN ANY FORM WITHOUT WRITTEN PERMISSION FROM THE PUBLISHER.

66 565 Fig 4 ACE Clss III: (left) Pretretment nd (right) posttretment views. In this deep ite ptient, severe loss of tooth structure t the level of the pltl spect wekened the vestiulr surfces (note the high trnslucency), ut the fcil surfce ws lmost intct (shortening of the clinicl crown less thn 2 mm). This ptient required only pltl onlys. No further tretment ws necessry to restore the mxillry nterior teeth. e tht ll teeth were vitl nd mintined vitlity fter tretment. this reserch in Genev, ll ptients (ACE Clss II) involved were treted s erly s possile. Since this prospective clinicl study does not hve control group of ptients who were left untreted nd restored lter with conventionl therpy, comprison etween the two different tretment plns is not possile. On the other hnd, this clinicl study will provide the first set of dt helping to confirm (or reject) the clinicl vlidity of this ultrconservtive dhesive pproch. ACE Clss III: Distinct dentin exposure on the pltl spect, dmge of the incisl edge length ( 2 mm) Suggested therpy: Pltl veneers If ptients re left untreted, erosion nd focl ttrition will eventully led to wekening of the thickness of the incisl edges of the mxillry nterior teeth, especilly if the verticl overlp (overite) is not significnt (Fig 4). When the incisl edges re ffected, ttentive ptients strt seeking help, driven mostly esthetic concerns. Ptients in this ctegory re generlly in their lte 20s or erly 30s. Since not ll of them re willing to receive orthodontic tretment to crete interrch spce in the nterior segments of their mouth, n increse of the verticl dimension of occlusion Volume 30, Numer 6, BY QUINTESSENCE PUBLISHING CO, INC. PRINTING OF THIS DOCUMENT IS RESTRICTED TO PERSONAL USE ONLY. NO PART OF THIS ARTICLE MAY BE REPRODUCED OR TRANSMITTED IN ANY FORM WITHOUT WRITTEN PERMISSION FROM THE PUBLISHER.

67 566 Fig 5 When the enmel frme is still present (mesil, distl, cervicl, nd vestiulr spects), the tooth presents higher resistnce to tensile ces. Adhesive restortions restoring the pltl spect re suject to less ending ces, nd their clinicl permnce is enhnced (tennis rcket theory) is necessry nd involves the reconstruction of the posterior teeth, which, t this stge, my present signs of erosion s well. The choice etween indirect or direct composite restortions is sed on the severity of the loss of tooth structure nd sometimes on the finncil sttus of the ptient. The finl restortive choice the posterior qudrnts (direct composite restortions or onlys) must lwys e driven minimlly invsive principles. Following the three-step technique to increse the verticl dimension of occlusion, the nterior mxillry teeth re restored with indirect restortions (composite pltl veneers), especilly if the nterior spce creted with the increse in the verticl dimension of occlusion is more thn 1 mm. Due to the miniml dmge to the vestiulr spect of these nterior teeth, there is often no need further tretment. If the vestiulr surfces of the mxillry nterior teeth re intct or only slightly dmged t the level of the incisl edges, fcil veneers my e considered n overtretment since the length could e reestlished mens of pltl veneers. An ttempt should e mde to mtch the color of the nturl tooth with the pltl veneers, since the horizontl flt junction etween the tooth nd pltl veneers my e difficult in terms of color lending. Shde modifiction could lwys e ttempted lter if necessry. The clinicin should hve discussion with ech ptient to determine if the ptient could e stisfied estheticlly without veneers. Even though no long-term followup dt re ville currently on the longevity of pltl veneers used to replce dmged incisl edges, these restortions hve n cceptle prognosis ACE Clss III ptients. Often, ll the mrgins of pltl veneers re onded to enmel. Furthermore, the teeth involved still preserve their enmel frme. In fct, looking from the pltl spect, this frme could e identified nd comprle to the frme of tennis rcket (tennis rcket theory, Fig 5). The mesil nd distl wlls of such erosion-ffected teeth re generlly still intct (unless Clss III restortions re present). The cervicl pltl enmel is lso mostly present s nd of 1 to 2 mm next to the gingivl mrgin. Finlly, the enmel t the vestiulr spect of the tooth is lmost completely intct in this clss of ptients (less thn 2-mm loss of incisl edge length). The Interntionl Journl of Periodontics & Restortive Dentistry 2010 BY QUINTESSENCE PUBLISHING CO, INC. PRINTING OF THIS DOCUMENT IS RESTRICTED TO PERSONAL USE ONLY. NO PART OF THIS ARTICLE MAY BE REPRODUCED OR TRANSMITTED IN ANY FORM WITHOUT WRITTEN PERMISSION FROM THE PUBLISHER.

68 567 According to the tennis rcket theory, compromised teeth with n lmost intct enmel frme will show surprisingly high resistnce to flexure during function (mstiction or occlusion). As consequence, pltl composite restortions, suject to less tensile ces, will lst longer. Severl studies hve demonstrted the importnce of the mrginl ridges posterior teeth. Restortions tht extend to the mesil nd distl spect, such s mesil occlusl distl restortions, gretly ffected the strength of the restored posterior teeth In the opinion of the current uthors, the mesil nd distl mrginl ridges of the nterior teeth my hve similr importnce to tht descried posterior teeth. Since their removl during pltl veneer preprtion could drmticlly compromise the flexure resistnce of the tooth, the interproximl contct point should e removed minimlly mens of n interproximl dimond strip or not e removed t ll. ACE Clss IV: Extended dentin exposure on the pltl spect, loss of the incisl length of the tooth (> 2 mm), preserved fcil enmel Suggested therpy: Sndwich pproch Most ptients in this ctegory re wre of their dentl prolem since they hve noticed the shortening of their clinicl crowns nd n increse in the trnslucency of the incisl edges, even though they might not relize the extent of the tooth destruction (Figs 6 to 6d). At this stge, the posterior teeth re often involved, especilly the premolrs. Since n increse in the verticl dimension of occlusion is mndtory to crete the necessry interrch spce the restortive mterils in the nterior nd posterior segments, the three-step technique should e followed. To restore the nterior mxillry teeth, the sndwich pproch is recommended. After the restortion of the pltl spect with composite veneers, the tretment should e completed with cermic fcil veneers. The veneers re necessry not only ecuse pltl veneers often do not mtch the color of the nturl teeth, ut lso ecuse there re no studies to document the longterm permnce of such lrge composite restortion in cse the fcil veneers re not plced. Some ptients in the ongoing Genev study hve decided not to otin fcil veneers nd re under strict monitoring. If the pltl veneers degrde t quick rte, cermic fcil veneers could e fricted t lter dte. On the other hnd, the reminder of ACE Clss IV ptients ll received the two nterior restortions, nd the preliminry results (up to 4 yers of follow-up without ny clinicl prolems) re very encourging (Figs 6e to 6h). While prepring these dmged teeth fcil veneers, ttention should e given to not remove the fcil enmel nd trnsm these ptients into ACE Clss V cses. Additive techniques (tested the dignostic mock-up) or very thin veneers should e dvocted. 36 For this second option, the technicin should not e concerned with the finl esthetic result (s the crowns), since these teeth re generlly still live nd their originl color should not need hevy modifiction. ACE Clss V: Extended dentin exposure on the pltl spect, loss of the incisl length of the tooth (> 2 mm), distinct reduction/loss of the fcil enmel Suggested therpy: Sndwich pproch (experimentl) Ptients who re treted t this lter stge, untuntely, my not hve fvorle long-term prognosis if their mxillry nterior teeth re restored using the sndwich pproch (Fig 7). In ddition to the reduced length of the remining clinicl crown, the lck of enmel on the fcil spect of the teeth compromises the qulity of the ond of the definitive veneers nd the flexure resistnce. There re no long-term clinicl studies reporting on the longevity of sndwich pproch in Clss V ptients. At the University of Genev, ptients in this ctegory were treted following the dhesive technique since the lterntive option (conventionl therpy) would require devitliztion of ll compromised teeth. Preliminry dt from the Genev Erosion study show very promising results: the cpcity of the sndwich pproch to keep the vitlity of ll treted teeth, ll rehilittions chieved very plesing esthetic result, nd tooth preservtion ws mximl. Nevertheless, ptients Volume 30, Numer 6, BY QUINTESSENCE PUBLISHING CO, INC. PRINTING OF THIS DOCUMENT IS RESTRICTED TO PERSONAL USE ONLY. NO PART OF THIS ARTICLE MAY BE REPRODUCED OR TRANSMITTED IN ANY FORM WITHOUT WRITTEN PERMISSION FROM THE PUBLISHER.

69 568 Fig 6 ACE Clss IV Figs 6 to 6d (left) Pretretment nd (right) postretment views of n nterior mxillry restortion. This ptient required sndwich pproch (composite pltl nd cermic fcil veneers). Figs 6e to 6h (left) Pretretment nd (right) posttretment views. In this ptient, the comintion of erosion nd focl ttrition led to complete loss of the incisl edges (more thn 2 mm). Composite veneers were used to restore the pltl spect; even though cermic fcil veneers were plnned to complete the tretment of these teeth, the ptient decided to wit since the difference in shde ws not visile t norml communiction distnce (1-yer follow-up). e tht ll teeth kept their vitlity fter tretment. should e intercepted nd treted whenever possile n optiml clinicl permnce of their rehilittion. ACE Clss VI: Advnced loss of tooth structure leding to pulp necrosis Suggested therpy: Sndwich pproch (highly experimentl) Ptients t this stge present severely compromised dentition (Fig 8). Generlly, even in the cse of significnt loss of pltl tooth structure, the pulp hs time to withdrw nd compromised teeth surprisingly preserve their vitlity, result of the slow progression of the erosive process. For tooth to lose vitlity ecuse of dentl erosion, very severe nd frequent cid ttck (eg, ulimic or norexic ptients) is necessry, which overcomes the cpcity of the pulp to protect itself, or simply n extreme destruction of its coronl dentin. In oth cses, tretment prognosis my The Interntionl Journl of Periodontics & Restortive Dentistry 2010 BY QUINTESSENCE PUBLISHING CO, INC. PRINTING OF THIS DOCUMENT IS RESTRICTED TO PERSONAL USE ONLY. NO PART OF THIS ARTICLE MAY BE REPRODUCED OR TRANSMITTED IN ANY FORM WITHOUT WRITTEN PERMISSION FROM THE PUBLISHER.

70 569 Fig 7 ACE Clss V: (left) Pretretment nd (right) posttretment views (2-yer followup). The dentl destruction hd involved lmost two thirds of the crown length nd the dentin ws exposed on the fcil spect. The sndwich pproch is considered experimentl in these cses, since the cermic fcil veneers re onded minly to reduced surfce of dentin. Fig 8 ACE Clss VI: (left) Pretretment nd (right) posttretment views. The dentl tissue destruction in this ptient ws so severe tht two teeth were not vitl t the time of the first consulttion. Since the lterntive ws the extrction of the four mxillry incisors, the ptient ws treted following the sndwich pproch. The 2- yer clinicl follow-up results re presented. e tht the pltl composite restortions were mde directly in the mouth, nd the veneers were fricted lortory technicin selected the ptient personl resons (completed in collortion with Dr H. Gheddf Dm). e poor, especilly if the erosion cnnot e controlled. In the uthors opinion, dhesive techniques should still e ttempted, even though long-term results re lcking. The sndwich pproch hs the dvntge of preserving the mximum tooth structure nd, in most cses, the tooth vitlity of the remining teeth.. So fr, in the Genev Erosion study, ptients in this ctegory hve mintined the vitlity of ll treted teeth. If loss of vitlity occurs s result of the severely ffected pulp of these teeth, endodontic ccess will e mde esier through the pltl veneer without dmging the fcil veneer. This would e more difficult in cses of full coverge. Another dvntge of the dhesive technique in cses of lter loss of vitlity is tht internl leching procedures could e done esily. On the contrry, in cses with conventionl therpy, the option to chnge the shde of discolored root visile fter gingivl recession is not ville ecuse of the presence of the post cemented in the root. Volume 30, Numer 6, BY QUINTESSENCE PUBLISHING CO, INC. PRINTING OF THIS DOCUMENT IS RESTRICTED TO PERSONAL USE ONLY. NO PART OF THIS ARTICLE MAY BE REPRODUCED OR TRANSMITTED IN ANY FORM WITHOUT WRITTEN PERMISSION FROM THE PUBLISHER.

71 570 Conclusion Dentl erosion is frequently underestimted pthology tht ffects n incresing numer of young individuls. Intercepting ptients t the initil stges of the disese is criticl to void irreversile dmge to their dentition nd to gurntee etter clinicl permnce of the restortions selected. In this rticle, new clssifiction is proposed to quntify the severity of the dentl destruction nd to guide clinicins nd ptients in the decision-mking process. The clssifiction is sed on severl prmeters relevnt oth the selection of the tretment nd the ssessment of the prognosis, such s dentin exposure in the pltl tooth contct res, ltertions t the level of the incisl edges, nd ultimtely, loss of pulp vitlity. Ptients re grouped into six clsses, nd ech, dentl tretment pln is suggested. For ptients in whom the severity vries depending on loction, the most compromised nterior tooth is selected to decide which clss the ptient elongs to. Finlly, with the exception of ACE Clss II, where minor orthodontic tooth movement my e considered, tretment of the erosion requires distinct ugmenttion of the existing verticl dimension of occlusion to crete the necessry spce to restore the mxillry nterior teeth. Consequently, direct or indirect restortions of the posterior qudrnts must lso e plnned s n integrl prt of the definitive orl rehilittion. Acknowledgment The uthors would like to thnk the following lortory technicins nd cermists their integrl support in completing these complex cses: Alwin Schönenerger, Ptrick Schnider, Pscl Müller, Serge Erpen, Sylvn Crciofo, nd Sophie Zweicker. Finlly, the uthors would like to cknowledge the collortion of Dr Hmst Gheddf Dm, Dr Giovnn Vglio, Dr Federico Prndo, Dr Lind Grutter, Dr Tommso Giovnni Rocc, nd Dr Julin Lurschi. References 1. Aud SM, Wterhouse PJ, Nunn JH, Moynihn PJ. Dentl cries nd its ssocition with sociodemogrphics, erosion, nd diet in schoolchildren from southest Brzil. Peditr Dent 2009;31: McGuire J, Szo A, Jckson S, Brdley TG, Okunseri C. Erosive tooth wer mong children in the United Sttes: Reltionship to rce/ethnicity nd oesity. Int J Peditr Dent 2009;19:91 98 [errtum 2009;19:222]. 3. Vn't Spijker A, Rodriguez JM, Kreulen CM, Bronkhorst EM, Brtlett DW, Creugers NH. Prevlence of tooth wer in dults. Int J Prosthodont 2009;22: El Aidi H, Bronkhorst EM, Truin GJ. A longitudinl study of tooth erosion in dolescents. J Dent Res 2008;87: Milosevic A, O'Sullivn E. Dignosis, prevention nd mngement of dentl erosion: Summry of n updted ntionl guideline. Prim Dent Cre 2008;15: Milosevic A. Gstro-oesophgel reflux nd dentl erosion. Evid Bsed Dent 2008;9: Shughnessy BF, Feldmn HA, Clevelnd R, Sonis A, Brown JN, Gordon CM. Orl helth nd one density in dolescents nd young women with norexi nervos. J Clin Peditr Dent 2008;33: Brtlett D. A new look t erosive tooth wer in elderly people. J Am Dent Assoc 2007;138(suppl):21S 25S. 9. Nunn JH. Prevlence of dentl erosion nd the implictions orl helth. Eur J Orl Sci 1996;104: The Interntionl Journl of Periodontics & Restortive Dentistry 2010 BY QUINTESSENCE PUBLISHING CO, INC. PRINTING OF THIS DOCUMENT IS RESTRICTED TO PERSONAL USE ONLY. NO PART OF THIS ARTICLE MAY BE REPRODUCED OR TRANSMITTED IN ANY FORM WITHOUT WRITTEN PERMISSION FROM THE PUBLISHER.

72 Hinds K, Gregory JR. Ntionl Diet nd Nutrition Survey: Children Aged 1? to 4? Yers. Vol 2: Report of the Dentl Survey. London: Office of Popultion Censuses nd Surveys, O Brien M. Children s Dentl Helth in the United Kingdom London: Office of Popultion Censuses nd Surveys, HMSO Lussi A, Schffner M, Hotz P, Suter P. Dentl erosion in popultion of Swiss dults. Community Dent Orl Epidemiol 1991; 19: Tylor DF, Byne SC, Sturdevnt JR, Wilder AD. Comprison of direct nd indirect methods nlyzing wer of posterior composite restortions. Dent Mter 1989; 5: Leinfelder KF, Wilder AD Jr, Teixeir LC. Wer rtes of posterior composite resins. J Am Dent Assoc 1986;112: Vilti F, Belser UC. Full-mouth dhesive rehilittion of severely eroded dentition: The three-step technique. Prt 3. Eur J Esthet Dent 2008;3: Vilti F, Belser UC. Full-mouth dhesive rehilittion of severely eroded dentition: The three-step technique. Prt 2. Eur J Esthet Dent 2008;3: Vilti F, Belser UC. Full-mouth dhesive rehilittion of severely eroded dentition: The three-step technique. Prt 1. Eur J Esthet Dent 2008;3: Brtlett D, Gnss C, Lussi A. Bsic Erosive Wer Exmintion (BEWE): A new scoring system scientific nd clinicl needs. Clin Orl Investig 2008;12(suppl 1):S Young A, Amechi BT, Dugmore C, et l. Current erosion indices Flwed or vlid? Clin Orl Investig 2008;12(suppl 1):S Holrook WP, Gnss C. Is dignosing exposed dentine suitle tool grding erosive loss? Clin Orl Investig 2008; 12(suppl 1):S Gnss C. How vlid re current dignostic criteri dentl erosion? Clin Orl Investig 2008;12(suppl 1):S Lussi A, Hellwig E, Zero D, Jeggi T. Erosive tooth wer: Dignosis, risk fctors nd prevention. Am J Dent 2006;19: Jeggi T, Grüninger A, Lussi A. Restortive therpy of erosion. Monogr Orl Sci 2006;20: Lussi A. Dentl erosion clinicl dignosis nd cse history tking. Eur J Orl Sci 1996; 104: Smith BG, Knight JK. An index mesuring the wer of teeth. Br Dent J 1984; 156: Eccles JD. Dentl erosion of nonindustril origin. A clinicl survey nd clssifiction. J Prosthet Dent 1979;42: Arnh AC, Edurdo Cde P, Cordás TA. Eting disorders. Prt II: Clinicl strtegies dentl tretment. J Contemp Dent Prct 2008;9: Arnh AC, Edurdo Cde P, Cordás TA. Eting disorders. Prt I: Psychitric dignosis nd dentl implictions. J Contemp Dent Prct 2008;9: Ali DA, Brown RS, Rodriguez LO, Moody EL, Nsr MF. Dentl erosion cused silent gstroesophgel reflux disese. J Am Dent Assoc 2002;133: Sundrm G, Wilson R, Wtson TF, Brtlett D. Clinicl mesurement of pltl tooth wer following coting resin seling system. Oper Dent 2007;32: Sundrm G, Brtlett D, Wtson T. Bonding to nd protecting worn pltl surfces of teeth with dentine onding gents. J Orl Rehil 2004;31: Ty FR, Pshley DH. Resin onding to cervicl sclerotic dentin: A review. J Dent 2004;32: Pnitvisi P, Messer HH. Cuspl deflection in molrs in reltion to endodontic nd restortive procedures. J Endod 1995; 21: Reeh ES, Messer HH, Dougls WH. Reduction in tooth stiffness s result of endodontic nd restortive procedures. J Endod 1989;15: Reeh ES, Dougls WH, Messer HH. Stiffness of endodonticlly-treted teeth relted to restortion technique. J Dent Res 1989;68: Mgne P, Belser UC. Novel porcelin lminte preprtion pproch driven dignostic mock-up. J Esthet Restor Dent 2004;16:7 16. Volume 30, Numer 6, BY QUINTESSENCE PUBLISHING CO, INC. PRINTING OF THIS DOCUMENT IS RESTRICTED TO PERSONAL USE ONLY. NO PART OF THIS ARTICLE MAY BE REPRODUCED OR TRANSMITTED IN ANY FORM WITHOUT WRITTEN PERMISSION FROM THE PUBLISHER.

73 572 The Interntionl Journl of Periodontics & Restortive Dentistry 2010 BY QUINTESSENCE PUBLISHING CO, INC. PRINTING OF THIS DOCUMENT IS RESTRICTED TO PERSONAL USE ONLY. NO PART OF THIS ARTICLE MAY BE REPRODUCED OR TRANSMITTED IN ANY FORM WITHOUT WRITTEN PERMISSION FROM THE PUBLISHER.

74 CLINICAL RESEARCH Tretment plnning of dhesive dditive rehilittions: the progressive wx-up of the three-step technique Frncesc Vilti, MD, DMD, MSc Privte prctice, Genev Dentl Tem, Genev, Switzerlnd Senior Lecturer, Deprtment of Fixed Prosthodontics nd Biomterils, University Clinic Dentl Medicine, Genev, Switzerlnd Sylvin Crciofo, MDT Chief Dentl Technologist, University Clinic Dentl Medicine, Genev, Switzerlnd Correspondence to: Dr Frncesc Vilti Genev Dentl Tem, Rue St-Léger 8, 1205 Genev; Tel.: ; Fx: ; E-mil: 2 THE INTERNATIONAL JOURNAL OF ESTHETIC DENTISTRY

75 VAILATI/CARCIOFO Astrct A full-mouth rehilittion should e correctly plnned from the strt using dignostic wx-up to reduce the potentil remkes, incresed chir time, nd lortory costs. However, determining the clinicl vlidity of n extensive wx-up cn e complicted clinicins who lck the experience of full-mouth rehilittions. The three-step technique is simplified pproch tht hs een developed to fcilitte the clinicin s tsk. By following this technique, the dignostic wx-up is progressively developed to the finl outcome through the interction etween ptient, clinicin, nd lortory technicin. This rticle provides guidelines imed t helping clinicins nd lortory technicins to ecome more proctive in the tretment plnning of full-mouth rehilittions, strting from the three mjor prmeters of incisl edge position, occlusl plne position, nd the verticl dimension of occlusion. (Int J Esthet Dent 2016;11:XXX XXX) 3 THE INTERNATIONAL JOURNAL OF ESTHETIC DENTISTRY

76 CLINICAL RESEARCH Introduction When dentition is severely compromised, full-mouth wx-up is generlly considered mndtory to ressure the clinicin tht the cse is comprehensively nlyzed. Untuntely, t the end of the therpy, clinicins often relize tht the initil full-mouth wx-up did not correspond to the finl outcome of the rehilittion, to the point tht questions rise s to its rel clinicl vlue. The reson this my e tht clinicins llow lortory technicins to mke independent decisions out severl clinicl prmeters, which increses the chnce error. An pproch hs een developed to simplify the full-mouth rehilittion tretment pln the three-step technique which considers three fundmentl prmeters: the verticl dimension of occlusion (VDO), the incisl edge position, nd the occlusl plne position. 1-7 Since the three-step technique dvoctes the principles of minimlly invsive to non-invsive dentistry, n increse of the VDO is strongly dvocted every full-mouth rehilittion to void the need tooth preprtion (dditive dentistry). In ddition, the incisl edge position of the finl restortions is essentil to stisfy the ptient s esthetic needs. Finlly, the occlusl plne position not only hs n importnt esthetic vlue, ut lso defines how to shre the interocclusl spce otined with the increse of the VDO t the level of the posterior teeth. In the uthors opinion, full-mouth wx-up where these three prmeters re considered t the sme time is risky. Since the prmeters re closely relted to ech other, chnge to one necessrily entils modifiction to nother. In this wy, the wx-up my ecome useless. For exmple, if mock-up is mde out of the full-mouth wx-up, nd the ptient sks the incisl edges to e shortened, the occlusl plne must lso e modified to void n unesthetic reverse smile; nd if this ltter spect is modified, the occlusl wx-up should e remde. The full-mouth wx-up hs then ecome useless. The three-step technique prefers, insted, prtil wx-up tht will progress fter eing evluted nd vlidted the clinicin t severl stges. In lortory step I, the lortory technicin will wx up only the vestiulr spect of the mxillry teeth, nd the clinicin will vlidte only the incisl edges nd the occlusl plne. In lortory step II, wx will e plced on the occlusl surfces of specific posterior teeth, nd the clinicin will pprove the occlusl plne position nd the increse of the VDO. Finlly, in lortory step III, the wx-up will recrete the pltl spect of the mxillry nterior teeth, nd the clinicin will give n opinion on the incisl length nd the increse of the VDO. Step I The esthetic Since stisfying the ptient s esthetic needs is mjor ojective, clinicins should tke the time to relly understnd wht will e considered esthetic ech ptient. Trying to impose the clinicin s tste on the finl restortions my e highly risky. The risk of not c- 4 THE INTERNATIONAL JOURNAL OF ESTHETIC DENTISTRY

77 VAILATI/CARCIOFO Fig 1 nd In cse of the destruction of the incisl edges, it is recommended to involve ptients s soon s possile in the importnt decision out the esthetic of their future smile, since not everyone is redy to ccept longer nd wider restortions. cepting the shpe of the mxillry nterior teeth is higher in ptients ffected dentl erosion, especilly in severe cses. Although these ptients clim to e disstisfied with their smile, they re often more ccustomed to the look of their irregulr, smll, nd yellowish teeth thn they imgine, nd drstic chnge cn e difficult them to ccept. To void lengthy discussions nd costly remkes, it is dvisle to identify the shpe nd color of the finl restortions s soon s possile. Lrger, longer, whiter teeth my e shocking the ptient, nd the initil negtive rection does not lwys chnge to n cceptnce of the new proposed smile design. A tridimensionl mock-up, which lso involves the mxillry posterior teeth, my e more useful to communicte with these ptients (Fig 1). 8 Consequently, in the three-step technique, while fullmouth wx-up is not considered necessry, more extended mock-up is fundmentl step understnding the ptient s esthetic wishes. This mock-up should e done s soon s possile, ee investing in n extensive wx-up of the posterior teeth. Following the three-step technique, the two csts (out of lginte impressions) re rticulted in mximum interocclusl position (MIP) on semi-djustle rticultor using fceow. The first prtil wx-up will cover only the vestiulr surfce of the mxillry teeth, sufficient to recrete the incisl edges nd the occlusl plne t the level of the mxillry teeth (mxillry vestiulr wxup). Inspired the photogrphs of the ptient s smile, the lortory technicin will focus exclusively on the esthetic ppernce, with mximum freedom of cretivity (Figs 2 nd 3). Since the rehilittion is driven minimlly invsive to non-invsive dentistry, lortory technicins should rememer to lwys thicken the teeth during this wx-up so tht the vestiulr spect of the teeth cn e left intct during the preprtion the finl fcil veneers (dditive wx-up). The use dif- 5 THE INTERNATIONAL JOURNAL OF ESTHETIC DENTISTRY

78 CLINICAL RESEARCH Fig 2 nd Mxillry vestiulr wx-up. Only the incisl edges nd the vestiulr cusps of the mxillry teeth re reconstructed in wx, where needed. The ntgonistic cst is not considered t this stge, since ee progressing to the occlusl wx-up, the esthetic occlusl plne should e vlidted cliniclly with the ptient. Fig 3 nd This simplified wx-up is then used to fricte vestiulr mock-up. Thnks to the limited wx on the pltl spect, the mock-up key will e very stle on the teeth, limiting the presence of excesses. Ptients could lso keep the mock-up nd remove it themselves simply pulling it in the vestiulr direction. c Fig 4 to c Lck of contrst etween the stone nd the wx did not llow the evlution of the thickness of the future restortions. A silicon index ws necessry to see the vestiulr spce occupied the wx, which in this specific cse ws insufficient non-invsive pproch. 6 THE INTERNATIONAL JOURNAL OF ESTHETIC DENTISTRY

79 VAILATI/CARCIOFO Fig 5 nd Mxillry vestiulr mock-up. To void ny occlusl preprtion of the mxillry posterior teeth, the dditive wx-up lowers the position of the initil occlusl plne, worsening the existing reverse smile. Thus, ee wxing the occlusl surfces of the posterior teeth, it is mndtory to confirm with the ptient the choice of longer nterior teeth to hrmonize the new occlusl plne. ferent color wx to llow the visuliztion of its thickness is fundmentl (Fig 4). At the completion of clinicl step I, while the ptient expresses n opinion on the look of the mxillry vestiulr mock-up, the clinicin should gther inmtion the restortion of the posterior teeth. In fct, the mjor gol in this mock-up visit is to vlidte the esthetic position of the occlusl plne (eg, hrmony with the incisl edges), so tht the lortory technicin hs helpful inmtion on how to shre the posterior interocclusl spce, which will e otined with the increse of the VDO (Fig 5). One of the vrints of clssic clinicl step I occurs in cses where there is n insufficient horizontl overlp of the mxillry nterior teeth. Generlly, to fricte the mxillry vestiulr wxup, wxing up the opposing rch is not considered, since the increse of the VDO hs not yet een decided. However, in cse the mndile hs protrusive position, the mxillry vestiulr wx-up could e used to lso determine the increse of the VDO cliniclly. In this cse, the lortory technicin would e instructed to lengthen the mxillry nterior teeth until their incisl edges overlp the ntgonistic teeth. The incisl edges of the wxed-up teeth should hve miniml horizontl nd verticl overlp (t lest 1.5 mm), nd miniml thickness (1.5 mm), to gurntee the strength of the finl restortions. During the mock-up visit, the clinicin, in ddition to evluting the esthetic outcome of the lengthened teeth, my lso register the ptient s occlusion t the new increse of the VDO sking the ptient to simply ite on the incisl edges of the mock-up, nd then inject ite registrtion mteril in the posterior sextnts (Fig 6). Another vrint to the clssic threestep pplies in cses ffected initil/ moderte dentl erosion where the tooth destruction is not sufficiently severe to justify the need fcil veneers. When the vestiulr spect of the mxillry nterior teeth is mostly intct, nd the ptient cn e restored only mens of pltl veneers, mock-up visit is not necessry, since the incisl edges THE INTERNATIONAL JOURNAL OF ESTHETIC DENTISTRY 7

80 CLINICAL RESEARCH VDO is more restricted the risk of set c Fig 6 to c A 23-yer-old ptient ffected severe dentl erosion. The lortory technicin ws instructed to lso consider the position of the mndiulr rch. During the wx-up, the mxillry incisors were lengthened until miniml overlp with the ntgonistic teeth (1.5 mm) ws chieved. During clinicl step I, with the mxillry vestiulr mock-up in plce, the clinicin evluted whether the length of the mock-up plesed the ptient. In ddition, the ite ws registered sking the ptient to ite on the mock-up while registrtion mteril ws injected into the posterior spces. nd the occlusl plne of the finl restortions cn esily e visulized with the csts nd the clinicl photogrphs of the ptient s smile. Step I (the mxillry vestiulr wx-up) is then skipped, nd the lortory technicin cn directly strt the wx-up of the posterior qudrnts, reducing the cost nd speeding up the therpy (MODIFIED three-step technique). 9 Step II The posterior support The im of lortory step II is to wx up the posterior teeth t n incresed VDO. This wx-up will involve only the occlusl surfces of the two premolrs nd the first molrs, nd will e used to fricte direct composite restortions mens of trnsprent keys. At this stge, the clinicin must e prepred to nswer three questions: How much to increse the VDO. How to distriute the posterior interocclusl spce otined with the increse of the VDO. Which posterior restortions to use during step II (direct nd/or indirect restortions). After hving estlished the esthetic occlusl plne in step I, in order to complete the occlusl surfces of the posterior teeth it is necessry to determine the increse of the VDO. As lredy mentioned, in cse of severely worn dentition, n increse of the VDO is inevitle to reduce the need sustntil tooth preprtion in generl, nd to void elective endodontic tretments, in prticulr t the level of the nterior teeth. Clinicins re generlly frid to increse the VDO, fering consequences t the level of the temporomndiulr joints. On the contrry, the cpcity to dpt to the chnge of the VDO is generlly remrkle However, while the posterior teeth conspicuous increse of the VDO is lwys fvorle to deliver thicker restortions nd void tooth preprtion, limittions exist in delivering too-ulky nterior restortions to reestlish the contct points. Consequently, the increse of the 8 THE INTERNATIONAL JOURNAL OF ESTHETIC DENTISTRY

81 VAILATI/CARCIOFO ting the nterior teeth too fr prt thn the ptient s poor dptility to the increse of the VDO. Since ech ptient presents different scenrio, creful evlution of the rticulted csts should e considered ee deciding on the increse of the VDO. The threestep technique suggests first mking n ritrry choice looking t the initil csts mounted on the rticultor. The increse of the VDO should e guided not only restortive needs, such s the type of restortive mteril selected (eg, cermic or composite), ut lso occlusl considertions. While deciding on the increse of the VDO, ttention should e pid to hrmonizing the curve of Spee nd correcting the deep ite, especilly in erosive ptients with reverse smile nd suprerupted mndiulr incisors. 15 To fltten the curve of Spee without orthodontic therpy, significnt mount of the spce otined with the increse of the VDO should e given to the mndiulr rch, leving less spce ville the mxillry posterior teeth. There re two extreme clinicl choices when considering the increse of the VDO (Fig 7). The first choice is to fvor the nterior teeth with miniml increse of the VDO, which will led to rehilittion with dequte finl contct points in the nterior qudrnts, ut thinner nd weker posterior restortions. In ddition, it will e difficult to correct the occlusl plne nd/or the deep ite. The second choice is to fvor the posterior teeth with mximum increse of the VDO, which will otin dequte thickness of the posterior restortions without ny tooth preprtion. At the sme time, it will e possile to hrmonize the occlusl plne nd improve the deep ite. However, the tretment will led to the cretion of n nterior open ite, which cnnot e corrected only mens of pltl veneers. With the second choice, orthodontic therpy could e considered fterwrds to restore the nterior contcts. The lest-fvorle solution with the second choice is to leve the ptient with n nterior open ite. In this unstle occlusl sitution, Fig 7 The increse of the VDO should e relted to the nterior nd posterior teeth. While the posterior restortions conspicuous increse is lwys uspicious, the nterior teeth there is limittion to incresing the size of their pltl spect. THE INTERNATIONAL JOURNAL OF ESTHETIC DENTISTRY 9

82 CLINICAL RESEARCH c d Fig 8 to d Progression of the wx-up to the posterior teeth. The esthetic occlusl plne hd indicted how much of the interocclusl posterior spce could e given to the mxillry posterior teeth. To know how much is left the mndiulr teeth, the increse of the VDO should e determined first. In this ptient, the ANTERIOR stop ws touching the ntgonistic teeth, nd the posterior spce otined ws considered sufficient to deliver thick-enough posterior restortions. Fig 9 nd Mxillry vestiulr wx-up nd ANTERIOR stop. Thnks to the presence of the ANTER- IOR stop, the posterior teeth were set prt. Their seprtion indicted the mximum possile increse of the VDO, which still llowed otining nterior contcts. The clinicin should now decide if the interocclusl spce is sufficient the posterior restortions selected. e tht the ANTERIOR stop in this ptient lso included mndiulr incisor. 10 THE INTERNATIONAL JOURNAL OF ESTHETIC DENTISTRY

83 VAILATI/CARCIOFO Fig 10 nd Progression of the wx-up shown in Fig 9, fter tking the decision on the mount of increse of the VDO. Michign occlusl splint should e worn every night to stilize the nterior contct nd void supreruption. Since the nterior teeth s coupling is the limiting fctor in the increse of the VDO, the lortory technicin should provide n ANTERIOR stop reconstructing in wx only the pltl spect of the two centrl incisors to the thickest cliniclly cceptle shpe. Only two centrl incisors re necessry to fricte the ANTERIOR stop, since leving the surfces of the djcent teeth free of wx llows etter judgment on the clinicl cceptility of the ulkier pltl surfces. With the models mounted on the rticultor, the clinicin cn visulize the interocclusl spce otined in the posterior sextnts when the csts touch t the level of the reconstructed centrl incisors, since this represents the mximum mount of the VDO possile to still reestlish nterior contcts. The clinicin should then decide if this increse of the VDO is sufficient the restortive needs of the posterior teeth or not, nd mke the clinicl choice of fvoring either the nterior or the posterior teeth (Figs 8 to 10). If the mndiulr nterior teeth present exposed dentin, they should lso e included in the tretment nd in the ANTERIOR stop. For the mndiulr (s well s the mxillry) nterior teeth, only few strtegic teeth should e wxed up (ie, the most vestiulr ones), to etter visulize the clinicl outcome. Thnks to this prtil wx-up, mlpositioned teeth cn e etter identified, nd the need orthodontic therpy my e dvocted. While reconstructing dmged mndiulr teeth in wx, the lortory technicin should e creful not to lengthen their incisl edges excessively, since these teeth often lredy present suprerupted position. In ddition, lengthening these teeth in the incisl direction will worsen the curve of Spee nd the verticl overlp (deep ite) (Fig 11). To fricte n ANTERIOR stop, three points should e identified: A Incisl edge of the finl restortion. B New contct point with the ntgonistic tooth fter n increse of the VDO. C Most cervicl mrgin of the finl restortion. 11 THE INTERNATIONAL JOURNAL OF ESTHETIC DENTISTRY

84 CLINICAL RESEARCH Fig 11 Restortion of the nterior teeth nd deep ite. To void worsening the deep ite, the clinicin nd lortory technicin should resist the tempttion to excessively lengthen the incisl edges of oth the mxillry nd mndiulr teeth. In prticulr, the mndiulr incisors re often suprerupted, so insted of lengthening their incisl edges, the contct point should e reched thickening the pltl spect of their ntgonistic teeth. Fig 12 Three points could e identified in n ANTERIOR stop. A decision on the position of the B point (new contct point t the increse of the VDO) should involve the clinicin, since the finl shpe my e ulkier thn nturl tooth, to llow lrger increse of the VDO. The clinicin should determine whether the new shpe is cliniclly cceptle to the ptient. The union of these three points defines the pltl shpe of the mxillry pltl restortions. The junction etween B nd C should e s stright s possile to void phonetic impirments nd plque ccumultion (clensility), ut to still gurntee support to the occlusl contct (mechnicl strength) (Fig 12). It is recommended tht the pltl wxup e kept inside verticl line pssing through the C point (the C line), plced on frontl plne. This line defines the most pltl limit where the occlusl contct (B point) could e plced (Fig 13). 12 THE INTERNATIONAL JOURNAL OF ESTHETIC DENTISTRY

85 VAILATI/CARCIOFO Fig 13 nd Incorrect ANTERIOR stops. In oth cses, the B point ws more pltl thn the C line, nd this shpe the finl restortions would not hve een tolerted the ptient. With just this miniml wx-up, the clinicin hs gined vlule inmtion on the increse of the VDO nd the reestlishment of the nterior contct points. The three-step technique recommends the rticultion of the models in MIP. However, more complex cses (eg, devited mndile), it is possile to reregister the position of the mndile t the incresed VDO during the mock-up visit, thnks to the presence of the AN- TERIOR stop, which could lso e used s n nterior jig. While the ptient is iting on the ANTERIOR stop, the interrch posterior spce is filled with registrtion mteril. The mndiulr cst cn then e remounted, since the occlusl spect of the posterior teeth is prtilly not covered the mock-up, nd the occlusl ite registrtions could e dpted on the models (Fig 14). While deciding on the increse of the VDO, the clinicin should lso consider how to distriute the otined interocclusl spce mong the posterior teeth. This decision will mostly e sed on the presence of exposed dentin (eg, teeth to e restored), nd the finnces of the ptient. The uthors elieve tht it is lso importnt to fltten the occlusl plne nd reduce the deep ite whenever possile to promote more freedom to the lterl excursions of the mndile. 15 c Fig 14 to c An ANTERIOR stop could ecome n nterior jig during the mock-up visit to rerticulte the csts t incresed VDO (cse completed with Dr. C Dmrdji). 13 THE INTERNATIONAL JOURNAL OF ESTHETIC DENTISTRY

86 CLINICAL RESEARCH Fig 15 The est view to nlyze rticulted csts is from the pltl/lingul spect. While lortory technicins re fmilir with this view, clinicins re not, since it is impossile cliniclly. From this view it is esier to visulize the occlusl plne, the curve of Spee, nd the suprerupted mndiulr nterior teeth. The posterior interocclusl spce could e shred in three different wys: 1) one-rch distriution; 2) two-rch distriution; 3) mixed distriution (Fig 15). One-rch distriution With this option, the spce is given to only one rch (mndiulr or mxillry). The dvntge of this option is the reduction in the overll cost of tretment, since only one rch is restored. In ddition, the spce otined the increse of the VDO will not e shred mong ntgonistic teeth. Consequently, the increse of the VDO could e kept smller, nd the open ite corrected more esily mens of pltl veneers. Untuntely, this option is not lwys possile due to clinicl limittions. For exmple, the posterior teeth of the unrestored rch should e intct (no dentin exposure), nd the existing occlusl plne of the ntgonistic teeth should e correct (Fig 16). Fig 16 nd One-rch distriution. The increse of the VDO required to repir the incisl edges ws miniml. Since the mxillry posterior teeth were intct, it ws decided to increse the VDO, restoring only the ntgonistic mndiulr teeth. 14 THE INTERNATIONAL JOURNAL OF ESTHETIC DENTISTRY

87 VAILATI/CARCIOFO Fig 17 nd Two-rch distriution. A moderte to severe cse of dentl erosion. Both the rches presented teeth with exposed dentin, so two-rch distriution ws necessry, requiring more spce t the level of the posterior teeth. Two-rch distriution This is the most common sitution, especilly in the cse of severe dentl wer, since untuntely the posterior teeth of oth the rches present exposed dentin nd need to e restored. The dvntge of this option is the possiility of chnging the position of the occlusl plne modifying oth the occlusl surfce of the mxillry nd mndiulr posterior teeth. One disdvntge is the cost, since the ptient hs to py full-mouth rehilittion, with the restortion of ll the posterior teeth. Another disdvntge is the necessity to shre the interocclusl spce otined with the increse of the VDO. For exmple, if 2 mm is ville t the level of the first molr, the two ntgonistic onlys shring the ville spce eqully will only hve 1-mm thickness, which my not e strong enough, especilly in ptients with prfunctionl hits (Fig 17). Mixed distriution This distriution mens tht oth the mxillry nd mndiulr posterior teeth will e restored, ut not ll of them. This is often the cse when there is n irregulr occlusl plne, with supreruption of some posterior teeth. To chieve correct occlusl plne, the suprerupted teeth will not e restored, if of course their occlusl surfce is intct. The dvntge of this option is tht it costs less nd hs shorter clinicl time compred to the two-rch distriution (Fig 18). Bee the lortory technicin strts the wx-up of the posterior teeth, the clinicin should lso hve n ide out which type of restortions will e delivered during step II provisionl nd/or finl so tht the wx-up cn e modified ccordingly. In this rticle, only the wx-up modifictions in cse of friction of provisionl restortions re discussed. When the dentition is prticulrly compromised nd/or mndiulr devition is present, it is preferle during step II to deliver provisionl posterior composite restortions, fricted directly in the mouth mens of trnsprent keys. This tretment is comprle to n occlusl ite onded 24 h in 15 THE INTERNATIONAL JOURNAL OF ESTHETIC DENTISTRY

88 CLINICAL RESEARCH Fig 18 nd Mixed distriution. In this erly cse of dentl erosion, the increse of the VDO ws miniml nd necessry mostly to reince the thin incisl edges. To reduce the numer of teeth to e restored nd to void shring the limited posterior interrch spce, only the mndiulr molrs nd the mxillry premolrs were restored. It ws possile to not include the remining posterior teeth in the rehilittion, since they did not present dentin exposure. e tht the wx-up of the pltl spect of ll the mxillry teeth ws not necessry. The ANTERIOR stop could e done with only one or oth centrl incisors. the mouth (therpeutic white ite). This is lso the fstest tretment to restore multiple teeth t the sme time (eg, in two-rch distriution) ptients who do not hve time or cnnot tolerte long ppointments. Following the three-step technique, these provisionl restortions will e replced fter the rehilittion of the nterior qudrnts the finl restortions. When the wx-up of the posterior teeth is used the friction of the provisionl restortions, it should e modified t four levels ee the friction of the trnsprent keys: 1) interproximl res; 2) mesil nd distl stops; 3) occlusl emrsures (mrginl ridges); nd 4) vestiulr/pltl surfce (one-third cervicl). In generl, the wx should e kept to minimum nd plced only on the occlusl surfces where the contct points of the white ite will e. The remining wx should e removed ee the friction of the keys to reduce the size of the provisionl composite restortions nd fcilitte their future removl. In ddition, the interproximl res should e clen of excess wx, to reduce the risk of interproximl excesses during the friction of the composite restortions. A mesil nd distl stop should lwys e identified nd left wxfree, to promote etter sitting of the trnsprent keys (ie, less occlusl djustments). Dmged vestiulr nd/or pltl surfces my lso represent dilemm during the wx-up. The lortory technicin should resist the tempttion of fully reconstructing in wx these dmged surfces, since the clinicin does not need to fricte the provisionl composite so close to the cervicl spect of the teeth (high risk of excess) (Fig 19). The only reson to extend the wx-up to the cervicl spect is if the supporting cusps re very compromised (eg, 16 THE INTERNATIONAL JOURNAL OF ESTHETIC DENTISTRY

89 VAILATI/CARCIOFO Fig 19 nd For white ite, the wx should e limited to the occlusl surfces only, even when the teeth re not intct in the cervicl third. This will gurntee etter onding conditions nd esier removl of the excesses. Fig 20 nd The posterior wx-up to fricte the trnsprent keys should e very precise t the level of the emrsures. Any excess of wx will led to n excess of composite in the mouth. The mrginl ridges could e wekened with sclpel to promote the opening of the contct points etween the direct restortions during mstiction. pltl mxillry cusps), nd the occlusl contcts of the white ite need to e reinced (ie, void sher filure). One of the limits of the white ite is the closed interproximl contct points. To try to fvor their opening during function, the occlusl emrsures of the wx-up could e wekened ccentuting the seprtion of the wxed-up mrginl ridges with sclpel (Fig 20). Finlly, it is worth rememering to lwys use different color wx, since the clinicin will use the contrst with the stone to get n ide of how much composite should e plced in the trnsprent keys (Fig 21). At the end of clinicl step II, ptients will present stle posterior support t n incresed VDO nd n nterior open ite. Thnks to this nterior spce, the mxillry nterior teeth will then e restored without ny tooth preprtion (mximum tooth preservtion) mens of pltl veneers (step III). To move to 17 THE INTERNATIONAL JOURNAL OF ESTHETIC DENTISTRY

90 CLINICAL RESEARCH Fig 21 The use of similr color etween the wx nd the cst mkes it very difficult to see the limits of the wx nd its thickness. e tht the mxillry cnine is not free of wx, nd if this is not removed, the trnsprent key will not hve its mesil stop. the next step, new impressions, n nterior ite registrtion in MIP, nd fceow re needed. Step III The nterior contcts In step III, the lortory technicin will recrete in wx the pltl surfces of the mxillry nterior teeth ee fricting the pltl veneers. The shpe of the two centrl incisors ws lredy proposed with the ANTERIOR stop, nd confirmed or chnged the clinicin (Fig 22). As previously mentioned, one of the dvntges of the three-step technique is the possiility of evluting nd, if necessry, correcting the outcome of previous steps. The increse of the VDO, otined during step II, could e modified during step III. In cse the lortory technicin relizes tht the clinicl increse of the VDO ws excessive to reestlish the nterior contcts mens of pltl veneers, he/she cn progress with the friction of the finl nterior restortions to the idel shpe, which will hve no contcts with the ntgonistic teeth. The clinicin will then ond these restortions nd djust the occlusion on the posterior teeth until the nterior teeth re in contct (decrese of the VDO). It is lso possile to correct the opposite sitution (increse of the VDO). In this scenrio, the VDO will e incresed on the rticultor dding wx on the posterior teeth, nd the pltl veneers will e fricted ccordingly. Once onded on the pltl veneers, s expected, the posterior teeth will no longer e in contct. To reestlish the posterior support, simple direct composite will e delivered dding mteril on the previously roughened surfces of the pre-existing contct points. To fcilitte this second option, the direct composite restortions should e mde in only one rch. If mjor increments of the VDO re necessry, new trnsprent keys could e used to speed up the tretment (Fig 23). Severl uthors hve set fundmentl guidelines the reconstruction of the pltl surfces of the mxillry nterior teeth, especilly considering the envelope of function However, following the three-step technique, the shpe of the mxillry nterior finl restortions is strongly dictted, not only restoring the dmged pltl spect, ut lso the need to estlish the nterior contcts fter the increse of the VDO. To chieve these contcts, 18 THE INTERNATIONAL JOURNAL OF ESTHETIC DENTISTRY

91 VAILATI/CARCIOFO Fig 22 Wxing up the centrl incisors to fricte the ANTERIOR stop llows the lortory technicin to discuss the shpe of the future pltl veneers. At this stge, the clinicin cn sk modifictions or ccept the proposed m. Fig 23 In this cse, the increse of the VDO otined with the white ite ws not sufficient. Insted of rescheduling the ptient, with the sme impression the pltl veneers, the lortory technicin wxed up the occlusl surfces of the mxillry teeth nd fricted the pltl veneers t the incresed VDO. Two trnsprent keys were used to increse the VDO ee onding the veneers. there is no hesittion to restore teeth to lrger size thn the nturl dentition. In ddition, clinicins often hve to fce nd solve dentl/skeletl discrepncies improved or ggrvted the increse of the VDO using restortive mens only, since this type of ptient ccepts the therpy ecuse of its simplicity (nd rpidity), nd frequently refuses orthodontic therpy nd even more frequently, orthognthic surgery. Theree, the lortory technicin will rrely e inspired the nturl dentition the nterior region of the mouth, nd will recrete the perfect shpe nd idel contct points. Overll, the restored teeth will lwys look wider in n nterior posterior direction thn the nturl dentition, nd lortory technicins should not feel uncomtle out delivering restortions with n unusul shpe. Even though it is expected tht the pltl spect of these restored teeth should not resemle the intct teeth, ppering thicker even t the incisl edges, there re limittions to how much the size cn e incresed. There re six mjor ojectives during step III (friction of the pltl veneers): Re-estlish nterior contcts points (B points), unless decided otherwise. Supported B points (eg, not on surfces tht re too inclined). BC line stright ( clensility nd phonetics). Smooth pltl surfces (no excessive ntomy). Mximum eft to correct or not ggrvte deep ite (minimum lengthening of oth the incisl edges of mxillry nd mndiulr teeth). No steep nterior guidnce (open incisl ngle). 19 THE INTERNATIONAL JOURNAL OF ESTHETIC DENTISTRY

92 CLINICAL RESEARCH Fig 24 nd Pltl veneers with pltl ntomy tht is too ccentuted, occupying spce the tongue without ny functionl purpose. In ddition, these veneers could e very uncomtle ptients who re ccustomed to concve shpe of eroded teeth. While defining the mximum thickness tolerted ech ptient, lortory technicins should er in mind tht ptients ffected dentl erosion re used to hving very flt/concve pltl surfces, nd tht they hve dpted the tongue to spek even with conspicuous loss of tooth structure, since this loss hs hppened progressively t very slow rte. Occupying the tongue spce with ulky pltl veneers ll t once will e immeditely considered uncomtle the ptient, especilly ecuse it would cuse the impirment of the pronuncition of some letters (eg, D-T sounds). In time, the tongue will eventully djust, ut there will e ptients who will struggle longer, nd who my pnic in the mentime. As generl rule, since the finl shpe will e igger, the size of the pltl surfces should e kept flt in the res cerviclly to the B point (stright BC line). Complicted occlusl ntomy should e voided, such s very deep pltl grooves nd/or pronounced cingul. In ddition, not only is more eft required, ut the surfces of the finl restortions will e more difficult to polish, nd the irregulr texture will e very uncomtle the ptient s tongue (Fig 24). During the friction of the ANTER- IOR stop, the lortory technicin focused only on sttic occlusl contcts, mostly nlyzing the shpe of the pltl surfce etween the B nd C points clensility nd prolems with phonetics. In this lortory step III, the surfce, comprised etween the B nd A points, will lso e considered, since this is the re involved in the eccentric movements (nterior guidnce). Severl uthors hve given guidelines to correlte the condylr inclintions with the steepness of the nterior guidnce, nd it is not the ojective of this rticle to nlyze the vlidity of the different methods to chieve correct occlusl scheme, especilly when there is no evidence to support the superiority of one method over the others THE INTERNATIONAL JOURNAL OF ESTHETIC DENTISTRY

93 VAILATI/CARCIOFO Fig 25 Incisl ngle. This ngle is defined the AB line (from the contct point to the incisl edge) nd the fcil surfce of the ntgonistic tooth. In the cse on the right, the incisl edges re too thick. Reducing their volume without compromising the mechnicl strength of the future pltl veneers will open the incisl ngle nd promote the freedom of the mndile in its functionl movements. Fig 26 To open the incisl ngle (1), the A point is moved more vestiulrly (2). The pltl veneer will stop with step (2), which will e filled the composite used during the onding procedure to smooth the trnsition nd improve the shde mtching with the remining tooth structure (3). As generl rule, since rigid rticultor cnnot duplicte the sophisticted mndiulr movement, the three-step technique promotes the use of the ptient s the finl rticultor to test the occlusion. Consequently, occlusl djustments in the mouth will lwys e required nd expected. 21 The use of composite the therpeutic ite nd the pltl veneers fcilittes this tsk. The eccentric movements re simply tested with the ptient sitting upright, not nesthetized, nd chewing smll piece of gum. It is very surprising how ptients know exctly which re the interferences during chewing when they re not nesthetized. Following the ptient s request, group function is often the pre- 21 THE INTERNATIONAL JOURNAL OF ESTHETIC DENTISTRY