Does a chitosan-containing dentifrice prevent demineralization around orthodontic brackets?

Transcription

1 Originl Article Does chitosn-contining dentifrice prevent deminerliztion round orthodontic brckets? Tncn Uysl ; Meltem Dery Akkurt b ; Mihri Amsyli c ; Sut Ozcn d ; Ahmet Ygci e ; Feridun Bsk f ; Deniz Sgdic g ABSTRACT Objective: To test the null hypothesis tht there is no significnt difference between the chitosncontining nd conventionl nonfluoridted dentifrices in inhibition of enmel deminerliztion round orthodontic brckets. Mterils nd Methods: Sixteen orthodontic ptients who were scheduled to hve extrction of four first premolrs for orthodontic resons were divided into two groups fter the power of the study ws estimted. Ptients in the experimentl group were instructed to use chitosn-contining dentifrice (AloeDent), nd ptients in the control group were instructed to use nonfluoridted dentifrice (Sensodyne Mint). After 60 dys, the teeth were extrcted nd longitudinlly sectioned. The deminerliztion ws ssessed by cross-sectionl microhrdness. The determintions were mde t the brcket edge cementing limits nd t occlusl nd cervicl points, 100 mm nd 200 mm wy from the edge. In ll these positions, indenttions were mde t depths of 10, 20, 30, 50, 70, nd 90 mm from the enmel surfce. Anlysis of vrince (ANOVA) nd Tukey test were used for sttisticl evlution t P,.05 level. Results: ANOVA showed sttisticlly significnt differences for the fctors of dentifrice type, position, nd depth (P 5.000). Sttisticlly significnt differences for microhrdness vlues between two tested dentifrices were observed up to 20 mm of depth from the enmel surfce (P,.05). Lower microhrdness vlues were found for nonfluoridted dentifrice. Significnt microhrdness differences were lso determined between mterils t occlusl nd cervicl 0 mm positions (P,.05). At these positions, chitosn-contining dentifrice showed lower deminerliztion thn the control. Conclusion: Chitosn-contining dentifrice my reduce the enmel declcifiction found in ptients with poor orl hygiene. The null hypothesis is rejected. (Angle Orthod. 2011;81: ) KEY WORDS: Chitosn; Tooth deminerliztion; Dentl cries; Orthodontic brckets Associte Professor nd Chir, Erciyes University, Fculty of Dentistry, Deprtment of Orthodontics, Kyseri, Turkey nd Visiting Professor, King Sud University, Riydh, Sudi Arbi. b Reserch Assistnt, Gülhne Militry Medicl Acdemy, Center of Dentl Sciences, Deprtment of Peditric Dentistry, Ankr, Turkey. c Reserch Assistnt, Gülhne Militry Medicl Acdemy, Center of Dentl Sciences, Deprtment of Orthodontics, Ankr, Turkey. d Reserch Assistnt, Gzi University, Fculty of Dentistry, Deprtment of Conservtive Dentistry nd Endodontics, Ankr, Turkey. e Reserch Assistnt, Erciyes University, Fculty of Dentistry, Deprtment of Orthodontics, Kyseri, Turkey. f Professor, Gülhne Militry Medicl Acdemy, Center of Dentl Sciences, Deprtment of Peditric Dentistry, Ankr, Turkey. INTRODUCTION Despite the dvnces in orthodontic mterils nd techniques, the development of cvittions round the brckets during tretment continues to be problem. 1 Fixed pplinces mke it difficult for young ptients to g Professor nd Deprtment Chir, Gülhne Militry Medicl Acdemy, Center of Dentl Sciences, Deprtment of Orthodontics, Ankr, Turkey. Corresponding uthor: Dr Tncn Uysl, Erciyes Üniversitesi, Diş Hekimliği Fkültesi, Ortodonti Anbilim Dlı, 38039, Melikgzi, Kyseri, Turkey (e-mil: tncnuysl@yhoo.com) Accepted: August Submitted: My G 2011 by The EH Angle Eduction nd Reserch Foundtion, Inc. DOI: /

2 320 UYSAL, AKKURT, AMASYALI, OZCAN, YAGCI, BASAK, SAGDIC mintin dequte orl hygiene during orthodontic tretment. 2 These pplinces re linked to high risk of developing white-spot lesions. 3 The prevlence of new declcifictions mong orthodontic ptients with fixed pplinces is reported to rnge from 13% to 75%. 3,4 Ptients with orthodontic brckets hve n elevted risk of cries, nd enmel lesions cn occur within month, irrespective of mechnicl plque control nd whether fluoridted dentifrice is used. 3,5,6 Severl methods hve been used to prevent or reduce enmel deminerliztion during orthodontic tretment, including fluoride ppliction in vrious forms, enmel selnts, rigorous orl-hygiene regimens using glss-ionomer cement for bonding brcket nd modified pplince designs. 7 9 Chitosn nd modified chitosns re interesting cndidtes in this respect. Chitosn, nturl liner biopolyminoscchride is obtined by lkline decetyltion of chitin Chitin is chemiclly polymeric N-cetyl-D-glucosmine nd is minly contined in the shells of crbs nd shrimps. 13 Prticulr properties of chitosn re especilly importnt. It hs ph of 6.3, which is suitble to buffer the orl ph vlue high enough to prevent the deleterious ction of orgnic cids on the tooth surfce. 14 This mteril is lso biocomptible nd biodegrdble. It is positively chrged nd combines with the bcteril cell wll nd membrne with bcteriosttic nd bctericidl results. 15,16 Muzzrelli et l. 17 demonstrted tht chitosn exhibit bctericidl ction ginst severl pthogens, including Streptococcus mutns. This is especilly importnt since S. mutns is known to be the principl etiologicl fctor of dentl cries. 18 Wter-soluble, reduced chitosn ws used s mouth-rinse gent, nd it displyed n ntibcteril nd plque-reducing ction. 19 Furthermore, recent studies hve demonstrted tht chewing chitosncontining gum effectively inhibited the growth of criogenic bcteri in sliv. 20 It is well-known tht sub-miniml inhibitory concentrtions of severl ntibcteril compounds impir expression or production of bcteril dhesions, thus interfering with dherence to nd coloniztion of host tissues. 21 Therefore, considering tht, prevention from bcteril dhesion cn esily be chieved in the orl cvity by the use of dentifrices contining these gents. Studies in dentl literture hve demonstrted the positive effects of chitosn-contining mterils on the ph chnges in bcteril dentl plque 14 nd lso showed good ntimicrobil effectiveness of these mterils In different perspective, morphous clciumphosphte contining orthodontic dhesive, ntibcteril monomer-contining dhesive, 25 nd different topicl gents 26 hve been investigted in reducing enmel deminerliztion round brckets. However, no in vivo studies hve been performed to investigte the efficiency of dentifrice on enmel deminerliztion round orthodontic brckets. Therefore, the im of this study ws to evlute the in vivo effects of chitosn-contining dentifrice in reducing enmel deminerliztion round orthodontic brckets nd to compre the chitosn-contining dentifrice with the conventionl nonfluoridted dentifrice. For these purposes, the null hypothesis ssumed tht there is no significnt difference between the chitosncontining nd nonfluoridted dentifrices in inhibition of enmel deminerliztion round orthodontic brckets. MATERIALS AND METHODS This study ws pproved by the Ethicl Committee on Reserch of the Gülhne Militry Medicl Acdemy, Ankr, Turkey. A power nlysis ws completed by G*Power Ver (Frnz Ful, Universität Kiel, Germny) softwre. Bsed on 1:1 rtio between groups, smple size of eight ptients in ech group would give more thn 80% power to detect significnt differences with 0.40 effect size nd t significnce level of Inclusion Criteri The inclusion criteri were s follows: N Extrction of first premolrs due to orthodontic resons; N No ctive cries lesions, no stining, no enmel defect, or no initil cries lesion on premolrs tht were plnned to be investigted; N Norml slivry flow rte (.1.0 ml/min); N Norml buffer cpcity (finl ph: ); N No llergic rection to ny of the ingredients in dentifrices; nd N Regulr tooth brushing hbit. Exclusion Criteri The exclusion criteri were s follows: N Poor orl hygiene, N Occurrence of llergic rection or mucosl irrittion due to ny of the ingredients in dentifrices, nd N Unexpected side effects. Sixteen orthodontic ptients who were scheduled to hve four first premolr teeth extrcted for orthodontic resons were invited to prticipte in the study ccording to selection criteri, nd ll ptients nd their fmilies provided informed consent. All ptients received full-mouth clening to remove plque in preprtion for bonding. For evluting the

3 CHITOSAN-CONTAINING DENTIFRICE DEMINERALIZATION 321 bseline deminerliztion vlues of ll selected teeth, portble bttery-powered lser fluorescence device, DIAGNOdent Pen (KVo, Germny), ws used. 22 The scores of two groups were less thn 13, nd this indictes tht there ws no deminerliztion; both were equivlent for cries risk. Ptients were divided into two equl groups: one experimentl nd one control. After orl hygiene trining, ptients were given one of the two dentifrices rndomly: N Group 1 (experimentl) ws given chitosn-contining dentifrice (AloeDent, Optim-Helth Nutrition Ltd, Crdiff, Wles, UK), nd N Group 2 (control) ws given nonfluoridted dentifrice (Sensodyne Mint, GlxoSmithKline Consumer Helthcre, Brentford, UK). Orthodontic brckets were bonded with Trnsbond XT (3M Unitek, Monrovi, Clif), resin-bsed composite. A 37% phosphoric cid gel (3M Espe, St Pul, Minn) ws used for 15 seconds. The teeth were rinsed with wter for 30 seconds nd dried with n oilfree source for 20 seconds. Trnsbond XT (3M Unitek) primer ws pplied to the etched surfce in thin film nd not cured. Adhesive pste ws pplied to the brcket bse (Dyn-Lok series, 3M Unitek), nd the brcket ws positioned on the tooth nd pressed firmly into plce. The excess dhesive ws removed from round the brcket with scler, nd the dhesive ws light cured from the mesil nd distl for 10 seconds ech (totl time 20 seconds). A light-emitting diode unit (Elipr Freelight 2, 3M-Espe) ws used for curing the specimens for 20 seconds. All ptients were instructed to brush their teeth twice dy with the given dentifrice nd were dvised ginst using ny dditionl preprtions. For the testing procedure, 32 brckets were bonded for ech group (16 upper nd 16 lower first premolrs in both groups). After 60 dys, the teeth were extrcted nd stored in refrigertor in flsks contining guze dmpened with 2% formldehyde, ph 7.0, until the nlysis. Deminerliztion ws evluted by crosssectionl microhrdness method ccording to the literture. 6,22 28 Cross-sectionl Microhrdness Anlysis One opertor who ws blinded from the group lloction crried out the microhrdness nlysis (Dr Ozcn). The roots of the teeth were removed with wter-cooled dimond disk. The crowns were hemisectioned verticlly into mesil nd distl hlves with lrge 15 HC wfering blde in n Isomet low-speed sw (Buehler, Lke Bluff, Ill). The hemisections were cut into cervicl portion nd n occlusl portion. Both portions were embedded in self-curing epoxy resin (Epo-Kwick, Buehler), leving the cut fce exposed. The hlf crown sections were polished with brsive pper discs (320, 600, nd 1200 grit) nd polished with 1-mm dimond spry nd cloth polishing disc (Buehler). A microhrdness tester (HMV-700, Shimdzu, Kyoto, Jpn) under 2N lod for 15 seconds ws used for the microhrdness nlysis. Forty-eight indenttions were mde in ech hlf crown from eight positions nd six depths ccording to the definitions of Pscotto et l. 6 On the buccl surfce, indenttions were mde under the brcket. In the occlusl nd cervicl regions, indenttions were mde t the edge (0) of the brcket nd t 100 mm nd 200 mm wy from it. Indenttions were lso mde in the middle third of the lingul surfce of ech hlf crown, s nother control. In ll these positions, six indenttions were mde t 10, 20, 30, 50, 70, nd 90 mm from the externl surfce of the enmel. The vlues of Vickers hrdness number (VHN) found in the two hlf crowns were verged. Sttisticl Anlysis Dt nlyses were performed by using Sttisticl Pckge for Socil Sciences (SPSS, Ver 13.0, SPSS Inc, Chicgo, Ill). The Shpiro-Wilks normlity test nd the Levene vrince homogeneity test were pplied to the microhrdness dt. The dt showed norml distribution, nd there ws homogeneity of vrinces between the groups. Anlysis of vrince (ANOVA) ws used to evlute the effect of mterils, depths from the enmel surfce, positions, nd their interctions. For multiple comprisons, the Tukey honestly significnt difference (HSD) test ws used. The sttisticlly significnt level ws set t P,.05 level. For evluting the intr- nd interobserver greement, the microhrdness mesurements were done by two investigtors using the sme instrument t two seprte times, nd Cohen s kpp scores were determined. RESULTS The kpp scores for the ssessment of intr- nd interobserver greement were higher thn 0.80, which implies substntil greement between the observers. ANOVA showed sttisticlly significnt differences for the fctors of dentifrice type, position, nd depth (P 5.000). The interctions (dentifrice type/position, dentifrice type/depth, position/depth nd dentifrice type/position/depth) were lso sttisticlly significnt (P 5.000) (Tble 1). Descriptive sttistics nd multiple comprisons of microhrdness for chitosn-contining nd conven-

4 322 UYSAL, AKKURT, AMASYALI, OZCAN, YAGCI, BASAK, SAGDIC Tble 1. Sttisticl Comprisons nd the Results of ANOVA Source Sum of Squres Degrees of Freedom Men Squre F Sig Dentifrice type 152, , , * Position 303, , , * Depth 1,458, , , * Dentifrice type * position 202, , , * Dentifrice type * depth 1,431, , , * Position * depth 293, , , * Dentifrice type * position * depth 188, , , * Adjusted R squred * Sttisticlly significnt (P,.05). tionl nonfluoridted dentifrice t different depths from the enmel surfce re shown in Tble 2. The interction between dentifrice type nd depth hd significnt differences t the depths of 10 mm nd 20 mm from the enmel surfce. Less deminerliztion ws found on enmel round the brckets for the experimentl group compred with the control group. All descriptive sttistics nd multiple comprisons of microhrdness of two dentifrice systems t different observtion positions re shown in Tble 3. Sttisticlly significnt microhrdness differences were determined for the two tested groups (P,.05). Chitosncontining dentifrice showed higher microhrdness (occlusl 0 mm: VHN; cervicl 0 mm: VHN) thn the conventionl dentifrice (occlusl 0 mm: VHN; cervicl 0 mm: VHN). All descriptive sttistics nd multiple comprisons of microhrdness of two dentifrice systems nd positions t depths of 10 mm nd 20 mm re shown in Tble 4. The highest deminerliztion vlues were determined t occlusl nd cervicl 0 mm positions for the control group t 10 mm nd 20 mm depth. According to these results, the null hypothesis of the present study is rejected. DISCUSSION Present findings showed tht the use of chitosncontining dentifrice during 60 dys of orthodontic tretment ws ble to prevent deminerliztion of enmel, nd its use cn be suggested in prevention of white-spot lesions. To our knowledge, this study is the first to compre the use of specific dentifrice with conventionl nonfluoridted dentifrice by evluting condition with microhrdness testing enmel deminerliztion round orthodontic brckets in n in vivo condition, by microhrdness testing. In the pst, to use fewer ptients nd for ethicl considertions, preventive effects of vrious products such s fluoride-relesing mterils ginst deminerliztion were investigted by using split-mouth study design. 27 A split-mouth design ws unsuitble for this investigtion. Moreover orl hygiene chrcteristics re not lwys homogeneously distributed over the within-ptient experimentl units, nd this heterogeneity cn reduce the efficiency of split-mouth designs. As suggested by Pscotto et l., 6 the current experimentl design ws chosen insted of the split-mouth technique to void the crry-cross effect. Therefore, subjects were divided into two groups. The bseline clinicl, rdiologic, slivry, nd lser fluorescence ssessments were done for stndrdiztion. It ws determined tht ll ptients in both groups were equivlent with regrd to cries risk or deminerliztion ctivity. Insted of in vitro studies with extrcted teeth, our model hd severl dvntges 27 : the development of the cries lesions ws studied in vitl teeth; miniml ptient coopertion ws required; no specil diet ws required; nd becuse the protected enmel surfce llowed the ccumultion of thick plque, no other site ws t risk of cries with this procedure. Tble 2. Descriptive Sttistics nd Multiple Comprisons of Microhrdness (VHN) for Chitosn-contining nd Conventionl Dentifrice Systems t Different Depths From the Enmel Surfce Interction of Dentifrice Type/Depth, mm Nonfluoridted Dentifrice Chitosn-contining Dentifrice Men SD Men SD Multiple Comprisons * * NS NS NS NS Tukey HSD test. NS indictes not significnt. * Sttisticlly significnt (P,.05).

5 CHITOSAN-CONTAINING DENTIFRICE DEMINERALIZATION 323 Tble 3. Descriptive Sttistics nd Multiple Comprisons of Microhrdness (VHN) of Two Dentifrice Systems t Different Observtion Positions Interction of Dentifrice Nonfluoridted Dentifrice Chitosn-contining Dentifrice Type/Position Men SD Men SD Multiple Comprisons Occlusl 200 mm NS Occlusl 100 mm NS Occlusl 0 mm * Under brcket NS Cervicl 0 mm * Cervicl 100 mm NS Cervicl 200 mm NS Lingul NS NS indictes not significnt. * Sttisticlly significnt (P,.05). The deminerliztion vlues of enmel under two internl controls (under the brcket nd t the lingul surfce) bonded to the two types of teeth were used to evlute the effect of cid etching nd enmel deminerliztion. 6 In this study, the minerl loss ws ssessed by cross-sectionl microhrdness, n ccepted nlytic method. This method ws preferred to evlute deminerliztion nd cries becuse strong correltion coefficient (r ) ws reported by Fetherstone nd coworkers 28 between enmel microhrdness scores nd the percentge of minerl loss in the cries lesions. Pscotto et l. 6 observed reduced enmel hrdness in the cervicl region of the brcket compred with tht in the occlusl re. These findings were similr to current findings. In vivo, the explntion for this my be tht the greter dentl plque ccumultion nd ptient difficulty in clening this re. In vitro, the explntion would be less minerliztion nd higher crbonte on the cervicl surfce thn in the occlusl region. 6 Interestingly in the present study, different from the previous findings, 6,27,28 similr minerl loss ws observed t the cervicl nd the occlusl region t 0 mm positions. Sttisticlly significnt microhrdness differences were determined t these regions between the tested mterils. Control group showed lower hrdness vlues tht indicte more minerl loss thn the tested mterils. While others hve reported tht the deminerliztion of the enmel round orthodontic brckets cn extend s fr s 75 mm below the enmel surfce, Gorton nd Fetherstone 1 nd Pscotto et l. 6 reported tht enmel deminerliztion extended to only 30 mm from the enmel surfce in vivo. They permitted their subjects to brush their teeth, which most probbly removed some or ll of the plque nd microorgnisms ccountble for deminerliztion. In this study, for extensive nd controlled ssessment, the indenttions we mde were t 10, 20, 30, 50, 70, nd 90 mm from the externl surfce of the enmel to observe minerl chnges t the outermost prt of the enmel. The Tble 4. Descriptive Sttistics nd Multiple Comprisons of Microhrdness (VHN) of Two Dentifrice Systems nd Positions t Depth of 10 nd 20 mm Nonfluoridted Dentifrice Chitosn-contining Dentifrice Multiple Depth, mm Position Men SD Minimum Mximum Men SD Minimum Mximum Comprisons 10 Occlusl 200 mm NS Occlusl 100 mm NS Occlusl 0 mm * Under brcket NS Cervicl 0 mm * Cervicl 100 mm NS Cervicl 200 mm NS Lingul NS 20 Occlusl 200 mm NS Occlusl 100 mm NS Occlusl 0 mm * Under brcket NS Cervicl 0 mm * Cervicl 100 mm NS Cervicl 200 mm NS Lingul NS NS indictes not significnt. * Sttisticlly significnt (P,.05).

6 324 UYSAL, AKKURT, AMASYALI, OZCAN, YAGCI, BASAK, SAGDIC results of the current study demonstrte tht, up to 20- mm depth from enmel surfce, the microhrdness vlues for nonfluoridted dentifrice were lower thn for the experimentl dentifrice, nd the difference ws sttisticlly significnt. Different from our findings, de Mour et l. 27 found lesion depths up to 70 mm from the enmel surfce. Our results showed tht deminerliztion existed only up to 20 mm of depth from the enmel surfce. This could be explined by the experimentl model used; they llowed more plque ccumultion nd impired its removl by tooth brushing. Multiple comprisons of deminerliztion for dentifrice type nd position t the 10 mm depth from the enmel surfce showed sttisticlly significnt differences t ll positions in both the cervicl nd occlusl mrgins evluted on the buccl surfce. Orthodontic ttchments mke ptient s dentl hygiene more difficult, nd the ccumultion of plque is esier round the brckets. Our results confirmed this by showing the lower deminerliztion vlues t the occlusl nd cervicl mrgins t 0 mm positions (Tble 3). To dte, the use of chitosn-contining chewing gum nd mouth rinse hs been found to be n effective method for preventing deminerliztion of enmel. Hyshi et l. 20 hve reported tht chitosn-contining chewing gum ws more effective thn chitosn-contining mouth rinse. Hyshi et l. 20 hve lso reported tht chitosn relesed from the gum bse could be preserved t the bcteriosttic level in the sliv. The ntimicrobil ctivity of chitosn is dependent on its moleculr weight nd degree of decetyltion. 29 Fujiwr et l. 15 hve proved tht the highly decetylted nd lower moleculr chitosn showed bctericidl ctivity. Present findings suggested tht the supplementtion of chitosn to dentifrice is n effective method to control the deminerliztion of enmel round brckets. CONCLUSION N Chitosn-contining dentifrice my reduce the enmel declcifiction found in ptients with poor orl hygiene. REFERENCES 1. 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7 CHITOSAN-CONTAINING DENTIFRICE DEMINERALIZATION Uysl T, Amsyli M, Ozcn S, Koyuturk AE, Akyol M, Sgdic D. In vivo effects of morphous clcium phosphte contining orthodontic composite on enmel deminerliztion round orthodontic brckets. Aust Dent J. 2010;55: Uysl T, Amsyli M, Ozcn S, Koyuturk AE, Sgdic D. Amorphous clcium phosphte-contining orthodontic composites. Do they prevent deminerlistion round orthodontic brckets? Aust Orthod J. 2010;26: Uysl T, Amsyli M, Ozcn S, Koyuturk AE, Sgdic D. Effect of ntibcteril monomer contining-dhesive on enmel deminerliztion round orthodontic brckets. In vivo study. Am J Orthod Dentofcil Orthop. In press. 26. Uysl T, Amsyli M, Koyuturk AE, Ozcn S. Effects of different topicl gents on enmel deminerliztion round orthodontic brckets. In vivo nd in vitro study. Aust Dent J. 2010;55: de Mour MS, de Melo Simplício AH, Cury JA. In-vivo effects of fluoridted ntiplque dentifrice nd bonding mteril on enmel deminerliztion djcent to orthodontic pplinces. Am J Orthod Dentofcil Orthop. 2006;130: Fetherstone JBD, ten Cte JM, Shriti M, Arends J. Comprison of rtificil cries-like lesion by quntittive micrordiogrphy nd microhrdness profiles. Cries Res. 1983;17: No HK, Prk NY, Kee SH, Meyers SP. Antibcteril ctivity of chitosns nd chitosn oligomers with different moleculr weights. Int J Food Microbiol. 2002;74:65 72.