Contemporary Management of Generalized Erosive Tooth Surface Loss

Transcription

1 Mitl Ptel Dvid Seymour nd Mrtin F W-Y Chn Contemporry Mngement of Generlized Erosive Tooth Surfce Loss Astrct: Mngement of generlized erosive tooth surfce loss cn e chllenging. Creful pre-opertive ssessment of the ptient nd tretment plnning is essentil. The im of ny tretment provided is to prevent further tooth surfce loss, restore esthetics nd function, nd provide stle occlusl reltionship. Whilst ttempting to fulfil these gols, it is importnt to protect the remining tooth structure y using restortions which re conservtive nd do not cuse further dmge to teeth which re lredy compromised. This pper ims to descrie conservtive pproch to restoring ptients with generlized tooth surfce loss. Clinicl Relevnce: To highlight conservtive tretment options ville for the mngement of generlized erosive tooth surfce loss nd show how they contrst with other destructive irreversile conventionl techniques. Dent Updte 2013; 40: Acid erosion is defined s the dissolution of dentl hrd tissues y cid derived from extrinsic nd intrinsic sources (Tles 1 nd 2) ut not from cteri which re prt of the intr-orl flor. 1 Erosive tooth surfce loss is highly prevlent nd growing prolem in terms of mngement. 2 The 2003 survey of Children s Dentl Helth in the UK 3 showed tht 53% of 5-yer-olds nd third of yer-olds showed signs of tooth surfce loss which ws predominntly erosive in nture. This ws 1 5% increse from the 1993 survey. 4 The Adult Dentl Mitl Ptel, BSc(Hons), BDS, MFDS RCS(Eng), MSc, FDS(Rest Dent) RCPS(Glsg), Specilist Registrr in Restortive Dentistry, Dvid Seymour, BChD, MFDS RCS(Ed), Specilty Trinee in Restortive Dentistry, Mrtin F W-Y Chn, BDS, MDSc, MRD RCS(Ed), DRD RCS(Ed), FDS(Rest Dent), RCPS(Gls), Consultnt in Restortive Dentistry, Deprtment of Restortive Dentistry, Leeds Dentl Institute, Clrendon Wy, Leeds LS2 9LU, UK. Helth Survey in lso showed tht two-thirds of dults exmined hd signs of tooth surfce loss into dentine on their nterior teeth nd this ws shown to increse with ge. Tooth surfce loss, which develops slowly with incresing ge, is considered to e physiologicl, however, if ptient presents with tooth surfce loss tht is disproportionte to his/her ge, or if the vitlity of the tooth is thretened, then it is considered to e pthologicl nd some intervention my e necessry to prevent further tooth surfce loss or to restore the worn teeth. Erosive tooth surfce loss Mngement of tooth surfce loss cn e chllenging, especilly if extensive tooth tissue hs een lost. An ccurte dignosis of the etiology is importnt in identifying the custive fctors nd providing preventive dvice to the ptient prior to ny restortive tretment eing crried out. In most cses, there re often smll elements of ttrition nd/or rsion lso present, mking it condition of multifctoril etiology. 6,7 A significnt numer of ptients with erosive tooth surfce loss will hve no complints or my e unwre of it. If the ptient is unwre of the tooth surfce loss, it is the responsiility of the dentist to mke him/her wre of it nd identify the cuse t n erly stge. Where the tooth surfce loss is miniml nd the ptient hs no complints, mngement cn e kept simple with preventive dvice nd monitoring using silicone indices, photogrphs nd study models. Ptients with more dvnced tooth surfce loss my present with n esthetic concern or complining of functionl prolems due to the loss of stle occlusl contcts. The mjority of these ptients do not complin of sensitivity, ut those tht do my hve ongoing erosive tooth surfce loss where the teeth re eing exposed to highly frequent rte of cidic chllenge. 8 Ptients with dvnced tooth surfce loss will require some form of intervention to protect the remining tooth structure nd, in most cses, restore their worn dentition to improve the esthetic ppernce nd provide stle occlusl reltionship in order to improve function. The extent of 222 DentlUpdte April 2013

2 Intrinsic Acid (Reflux of gstric cid) Tle 1. Sources of intrinsic cid. Extrinsic Acids Alcohol Soft drinks Food stuff Mediction Environmentl Occuptionl Common cuses: Tle 2. Sources of extrinsic cids. Incresed pressure on stomch from pregnncy, oesity or incresed gstric volume from over eting or eting lte t night Voluntry repeted induced vomiting often ssocited with eting disorders such s ulimi nervos nd norexi nervos Rumintion syndrome reflux of swllowed food for further mstiction Gstro-oesophgel reflux disese (GORD) ssocited with: -Hitus herni (wekening of lower oesophgel sphincter) -GI trct disturnces (duodenl ulcer, chronic constiption) -Chronic lcoholism Side-effects of certin medictions my induce vomiting or decrese uffering cpcity of sliv due to drug-induced xerostomi Vomiting cused y chemotherpy nd rdiotherpy tretment for cncer Athletic nervos voluntry regurgittion in thletes to mintin ody weight, eg rce jockey Wine, Beer, Alcopops, Cider, Spirit mixers Fruit juices Flvoured wter Cronted drinks (NB Cronic cid is wek cid nd itself does not cuse erosion: it is other cids in soft drinks such s citric cid which cuse erosion) Fruit flvoured tes/herl tes Sports/Energy drinks, eg Lucozde sport, Red Bull, Mxim Pickles Fruits, eg ornges nd lemons Vinegr-sed foods Yoghurt-sed foods Vitmin C, Iron tlets Chlorine from swimming pools Working in cid environment tooth surfce loss cn e either loclized to few teeth or generlized to involve most of the teeth in oth the mxill nd mndile. Erosive tooth surfce loss cn ffect ny tooth surfce. 9 Erly erosive lesions my show smooth silky-glzed or dull enmel surfces with the sence of perikymt. Moderte cses often show cupping defects nd dvnced lesions present with most of the enmel eing lost, however, there is often n intct ring of enmel which remins round the gingivl mrgin. 8 These lesions re usully well into dentine, often into tertiry dentine. Ptients with generlized tooth surfce loss rrely pper to hve lost ny occlusl verticl dimension, despite the significnt generlized loss in clinicl crown height. 10 This is often due to the fct tht erosive tooth surfce loss is usully slowly progressing condition which llows time for compenstory lveolr down growth of the mxill to occur. 11 In ptients where the tooth surfce loss is ctive nd rpidly progressing, this compenstion my not e fst enough nd cn result in the ptient presenting with reduced lower fce height due to loss in occlusl verticl dimension. 12 Ptients with loclized tooth surfce loss lso mintin their occlusl verticl dimension, ut often lose interocclusl spce etween the worn teeth through loclized lveolr compenstion 11 nd over eruption of the worn nd opposing teeth. This is often seen in ptients who hve wer of their nterior teeth. 13,14 Tretment options Vrious restortions re ville for restoring teeth with tooth surfce loss. Trditionlly, comintion of metl cermic crowns, porcelin veneers nd gold crowns hve een shown to e successful in restoring function, esthetics nd occlusl stility. 15 The iggest disdvntge of these cst restortions is tht they re comprtively destructive to the lredy worn teeth nd cn lso result in the loss of vitlity of these teeth It is often difficult to explin to the ptient tht tretment of his/her tooth surfce loss will involve further removl of helthy tooth tissue. 10 In severe cses of erosion, removle prosthesis my e considered. 19 This cn e in the form of complete or prtil overdenture, only April 2013 DentlUpdte 223

3 denture or overly denture. Whilst these re non-destructive to tooth tissue, they cn e techniclly difficult to mke nd ptients my prefer to hve fixed replcement. With dvnces in onding techniques, the use of composite resin hs recently ecome populr, prticulrly for the restortion of loclized nterior tooth surfce loss, however, there is very little literture on the use of composite for uilding up posterior worn teeth This rticle presents cse of generlized tooth surfce loss which hs een predominntly restored with composite resin nd miniml preprtion gold onlys on the lower first molrs. Cse report A 26-yer-old mle presented to the clinic with n esthetic concern nd lso complined of sensitivity to hot nd cold from his teeth. Following history nd clinicl exmintion, provisionl dignosis of ctive erosive tooth surfce loss ws mde. Further investigtion with diet sheet highlighted tht the primry etiologicl fctor ws the consumption of litre of cronted Col per dy. There ws lso some history of previous cid reflux nd herturn. From the extr-orl exmintion it ws noted tht the ptient showed none of the upper nterior teeth with the upper lip t rest ut, when the ptient smiled, the gingivl mrgins were slightly visile round the nterior teeth due to some lveolr compenstion (Figure 1). The horizontl incisl plne ppered flt (Figure 2) nd no longer followed the curvture of the lower lip. Intr-orlly the tooth surfce loss ws generlized, involving ll the teeth in oth rches nd extended into dentine (Figure 3). Anteriorly, there ws lso thinning nd chipping of the incisl edge resulting in reduced clinicl crown height (Figure 2). In occlusion, the ptient ppered to hve very slight decrese in lower fce height due to some loss in occlusl verticl dimension which hd not fully een compensted for y lveolr down growth of the mxill. This, long with the fct tht the ptient ws getting sensitivity to hot nd cold, suggests tht there ws some ctive erosion tking plce which ws resulting in rpid tooth surfce loss. There ws n ovious discrepncy Figure 1. Ptient with high lip line which shows the entire tooth nd some of the gingivl tissues. noted etween the ptient s intercuspl position nd the retruded contct position. In the intercuspl position, the ptient hd developed Clss III incisl reltionship. This ws due to the ptient posturing the mndile forwrds in order to mintin contct etween the worn nterior teeth. Cse mngement Initilly, discussion took plce with the ptient with regrds to diet nd prevention. The ptient ws dvised to reduce the mount nd frequency of cronted drinks he ws consuming, restrict them to mel times only nd use strw to prevent ny further erosive tooth surfce loss. Whilst the ptient ws not wre of ny ctive herturn or cid reflux tking plce, owing to the pst medicl history, the ptient s generl medicl prctitioner ws lso contcted to investigte further the possiility of silent cid reflux. Following preventive dvice, oth the ptient nd clinicin greed tht the tooth surfce loss ws dvnced enough to consider some form of restortive tretment to restore the worn teeth nd protect them from further tooth surfce loss. Restortive tretment options were discussed with the ptient which included, the use of direct nd indirect composite resin, porcelin fused to metl crowns, ll-cermic nd gold crowns or onlys. The ptient s tooth surfce loss ws not extensive enough to consider removle prosthesis. The use of composite resin to replce the worn tooth structure, restore esthetics nd function, whilst protecting the remining tooth structure, ws explined to the ptient in detil. The ptient ws informed tht this is the most conservtive form of tretment c d e Figure 2. Ptient s incisl plne is flt (red line) nd does not follow curvture of the lower lip. Incresed gingivl disply suggests tht there hs een some lveolr compenstion in the upper rch. Figure 3. ( e) Pre-opertive intr-orl views. 224 DentlUpdte April 2013

4 Figure 4. (, ) Chirside esthetic preview creted using orthodontic wx t initil ssessment visit. nd lterntive tretment would involve crowning severl teeth, which is more destructive. In order to explin the im of the tretment visully, chirside esthetic preview ws crried out using orthodontic wx (Figure 4). This technique involved dding orthodontic wx to the upper nterior six teeth to mke them roughly the idel size nd shpe, sed on the clinicin s experience nd knowledge of verge tooth dimensions. This llowed the ptient to see wht restortive tretment with composite resin could offer nd lso gve the clinicin n ide of how much the nterior teeth needed to e uilt up to restore esthetics, with teeth of idel size nd shpe nd the incisl plne following the lower lip line. This simple form of chirside esthetic preview lso helped in giving the lortory detiled prescription for the dignostic wx-up in terms of how much ech tooth needs uilding up nd how much increse in occlusl verticl dimension is required to chieve this result. The ptient ws hppy with the ppernce of the mock up nd ws keen to go hed with the composite uild-ups to restore his worn dentition. Impressions, fceow record nd n interocclusl retruded rc of closure record ws tken t the estimted increse in occlusl verticl dimension. Articulted study models nd dignostic wx-up were mde. This ws shown to the ptient nd the finl tretment pln greed. A Memosil (Hereus Kulzer, GMBH) index (Figure 5) ws mde from the dignostic wx-up for ech rch, which ws used to help guide restortion of the nterior teeth with composite resin sed on the mtrix technique descried y Roinson et l. 26 Prior to restoring the teeth with composite resin, the teeth were evelled nd clened with pumice to remove the slivry pellicle. Initilly, ll four cnine teeth were restored to estlish the new occlusl verticl dimension nd restore cnine guidnce in lterl excursions. This ws immeditely followed y restortion of the upper nd lower incisor teeth nd plcement of temporry composite stops (Figure 6) on the premolrs nd molrs to mintin the interocclusl spce creted y incresing the occlusl verticl dimension. The use of mtrix llowed the pltl contour nd incisl length of the teeth to e mpped out ccurtely with enmel shde composite s per the dignostic wx-up. This ws then used to guide the susequent plcement of the dentine shde of composite. In order to prevent onding composite to the djcent teeth, the initil enmel composite lyer on the pltl surfce uilt using the mtrix ws kept shy of the contct points. Following plcement of the dentine shde composite, the interproximl contct points were creted using enmel shde composite nd cellulose strip wrpped over the pltl surfce. The finl enmel lyer ws then plced to finish the restortion. Using the mtrix to recrete the contour of the pltl surfce s per the dignostic wx-up lso helped in developing stle occlusl reltionship, which required miniml djustment to ensure even occlusl contcts on ll the restortions. Once the nterior teeth in oth rches were complete, the premolrs nd the upper molr teeth were uilt up using comintion of the mtrix technique nd free-hnd uild-up technique, lso descried y Roinson et l. 26 The lower first molrs were restored with lmde gold onlys which were cemented using Pnvi (Kurry Dentl). All the composite restortions were completed y mintining moisture control using comintion of cotton wool rolls, tongue Figure 5. Memosil index mde from the dignostic wx-up to guide composite uild-ups. Figure 6. Exmple of composite stop plced on the posterior molrs whilst the nterior teeth re eing restored. gurd slivry ejector nd educting the ptient on the importnce of keeping the re dry. Mintining dequte moisture control to uild-up the lower molrs in composite ws difficult nd therefore it ws decided to restore these teeth with miniml preprtion gold onlys. The direct composite used ws Esthetix with Prime nd Bond NT onding gent (Dentsply, Germny). Figures 7 h show the posttretment views of the finl restortions. Discussion Before ny restortive tretment is commenced it is importnt to identify the cuse of tooth surfce loss s this cn help when deciding how to restore the worn teeth. For exmple, ptients who hve worn their teeth through clenching or grinding (ttrition) will need restortions 226 DentlUpdte April 2013

5 c d e f g tht cn withstnd incresed occlusl forces. These ptients lso need to understnd tht they re more likely to frcture or dmge restortions compred to someone with erosive or rsive tooth surfce loss. For these resons, these ptients my e etter treted with crowns or comintion of dhesive composite restortions with few crowns or onlys on strtegiclly selected teeth, such s cnines, premolrs nd/or molrs which my help to restore guidnce nd tke excessive forces off the dhesive restortions. In comprison to this, someone who hs lost tooth tissue through cid erosion cn, theoreticlly, e restored using dhesive techniques nd composite resin, s they re unlikely to generte incresed occlusl forces which could sher off the restortions. Clinicl ssessment During the clinicl ssessment it is importnt to ssess the ptient oth extr-orlly nd intr-orlly in detil. Extr-orl exmintion llows the ssessment of the mount of incisl disply with upper lip relxed nd while the ptient is tlking nd smiling. If the ptient hs no incisl tooth disply with upper lip relxed then there my e some scope to increse the length of the incisor teeth with the finl restortion. If there is lredy few millimetres (mm) of incisl tooth disply with the upper lip relxed, s shown in the ptient in Figure 8, or significnt soft tissue disply when the ptient smiles (Figure 8) (often seen when there is lveolr compenstion ssocited with tooth surfce loss), then it my not e possile to increse the length of the teeth. Incresing the length of the teeth through the restortion in this scenrio would result in too much incisl disply when the lip is t rest, mking the teeth pper s if they re too long, often giving poor esthetic ppernce. Insted, it my e more pproprite to crry out crown lengthening surgery 27,28 to lengthen the clinicl crown height, reduce the gummy nture of the smile nd restore the teeth to the idel length for the ptient. In some cses, comintion of incresing the length of teeth y few mm nd few mm of crown lengthening surgery my e necessry. The ptient in the cse presented here does hve high smile line with some gingivl disply (Figures 1 nd 2). However, owing to the lck of incisl tooth disply when the upper lip is t rest, it ws possile to uild the teeth up nd void the need for crown lengthening surgery without mking the teeth look too long. The pre-opertive esthetic preview which ws crried out helped in mking this decision. The postopertive view (Figure 7) lso shows tht the incisl plne hs een restored so tht line drwn long the incisl edges of the upper nterior teeth would e of similr curvture to the lower lip, which ppers more esthetic when compred to the flt incisl plne seen in Figure 2. Creting interocclusl spce for restortion of worn teeth The intr-orl exmintion will highlight if the wer is loclized to few teeth or generlized nd whether interocclusl spce is ville or not. In loclized wer of the nterior teeth, if spce is ville this cn e used simply to restore the teeth without the need for tooth preprtion or n increse in the occlusl verticl dimension. When interocclusl h Figure 7. ( h) Post-tretment views of the finl restortions. Figure 8. (, ) Exmple of clinicl cse where crown lengthening surgery is necessry. April 2013 DentlUpdte 227

6 spce is not ville, usully due to comintion of lveolr compenstion nd overeruption of worn nd opposing teeth, spce needs to e creted. Tooth preprtion is one method of creting spce. However, this should e voided s it is destructive to n lredy compromised tooth. Exmintion of the ptient s occlusion should e crried out to see if the occlusion cn e reorgnized y mnipulting the ptient s mndile into retruded contct positon. 15 This cn often crete spce nteriorly which cn e used to restore the loclized nterior wer. Creting even contcts etween the restortions nd opposing teeth will hold the mndile in the retruded contct position, mking this the ptient s new intercuspl position. In some cses where the retruded contct position is coincident with the intercuspl position, or if there is only smll difference etween the two, it my not e possile to crete spce s descried ove. In these cses, spce cn e creted using the Dhl principle. 29 Originlly, Dhl s work involved the use of n nterior cst colt chrome removle ite plne (Dhl pplince) which, when inserted, cused disclusion of the posterior teeth. Over n verge of 6 9 months, the posterior teeth re-estlished contcts through comintion of reltive intrusion of the nterior teeth nd overeruption of the posterior teeth. As result, interocclusl spce ws creted nteriorly which could e used to restore the worn teeth. This technique, over time, hs een descried s the Dhl principle. 30 The Dhl pplince itself hs een developed since it ws first descried, with mny uthors dvocting the use of direct composite restortions on the upper nterior teeth. These restortions re plced t n incresed occlusl verticl dimension with even occlusl contcts with the opposing nterior teeth in the retruded rc of closure. This results in disclusion of the posterior teeth, 12,21,22 which over n verge of 4 9 months often come ck into contct through reltive tooth movements, s descried ove, voiding the need for ny further tretment. 30 In cses of generlized tooth surfce loss, restoring only the nterior teeth is generlly not enough nd restortion of the posterior worn teeth is lso often required. In this sitution, the ptient my require complete reorgniztion of the occlusl scheme t n incresed occlusl verticl dimension to crete spce in the retruded rc of closure. The cse presented here hs een restored in this mnner with comintion of direct composites nd gold onlys. Stging of tretment When crrying out fullmouth rehilittion, s shown in the cse presented here, creful plnning is importnt to ensure ccurcy of the new occlusl scheme. In order to chieve this, it is importnt to crry out the tretment in stges over severl visits in short period of time. Building up strtegic teeth (often the cnines) in ech qudrnt initilly is importnt to estlish the new occlusl verticl dimension nd stle mndiulr position. Once this hs een done, the rest of the nterior teeth cn e restored one y one s quickly s possile to prevent ny uncontrolled/unfvourle tooth movement. Often, for the sme reson, while the nterior teeth re eing restored, it is worth plcing temporry composite stops (Figure 6) on the posterior teeth to mintin the interocclusl spce s it cn e while efore the posterior teeth re restored. If the creted spce etween the posterior teeth is not mintined, then restortion of these teeth my require preprtion of the teeth to crete more interocclusl spce. As mentioned efore, this is highly destructive to n lredy compromised tooth. Composite resin nd tooth surfce loss Indirect restortions re fr more destructive to tooth tissue ut less technique sensitive compred to composite resin. When using composite, the clinicin needs to e le to mintin dequte moisture control s well s hving the rtistic flre to crete tooth-like composite restortions. Although it would e desirle to use ruer dm, it cn e difficult when uilding up worn teeth with composite. Often, in the upper rch, moisture control is well mintined using cotton wool rolls, slivry ejectors, guze squres nd good ptient co-opertion. Mintining moisture control in this wy cn e difficult in the lower rch, prticulrly the posterior prts in the lower rch. Where dequte moisture control cnnot e chieved, either with the use of ruer dm or other techniques, composite resin should e voided. Alterntive indirect restortions should e considered where control of moisture is not required for such long periods of time. In this cse, gold onlys with miniml preprtion were plced on the lower molrs. Chn et l 31 showed tht these restortions re often successfully used in the posterior prts of the mouth where esthetics is not priority nd where moisture control cn e difficult to chieve. There is very little literture on the longevity of composite resins. The est ville evidence shows tht composite resin used to restore nterior worn teeth hs success rte of 89.4% over men 30-month follow-up period. 20 Poyser et l 32 lso found only 6% complete filure rte of composite restortions on worn lower nterior teeth over 2.5 yer follow-up period nd Redmn et l 21 showed survivl rtes of over 4.5 yers with direct nterior composites. The min cuses of filure were due to the composite wering wy over time nd mrginl discolortion. Conclusions The im of mnging the worn dentition should e to protect the remining tooth structure whilst restoring function, occlusl stility nd esthetics. From the ptient s point of view, the most importnt fctor is often the esthetic ppernce of his/her teeth. In order to chieve these gols, minimlly invsive pproch is preferred nd the use of direct composite restortions is well suited to this. Using composite to restore generlized erosive tooth surfce loss erly on in the tretment leves the option of more invsive restortions for the future, if necessry. The use of composite resin, s shown in the cse here, voids, or t lest delys, the ptient entering destructive restortive tretment cycle. Composite restortions lso provide good esthetics, re esy to repir if they frcture nd cn esily e refurished y polishing if they discolour over time. Despite the lck of long-term evidence for longevity of these restortions, the ovementioned enefits should plce composite towrds the top of the list when plnning tretment for ptients with erosive tooth surfce loss. 228 DentlUpdte April 2013

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