Demineralization around orthodontic brackets bonded with resin-modified glass ionomer cement and fluoride-releasing resin composite. Evaluating the effects of fluoride-releasing dental materials on adjacent interproximal caries. Mineral loss on adjacent enamel glass ionomer cements restorations after cariogenic and erosive challenges. A clinical comparison of glass ionomer, resin-modified glass ionomer and resin composite restorations in the treatment of cervical caries in xerostomic head and neck radiation patients. Hypermineralization of Dentinal Lesions Adjacent to Glass-ionomer Cement Restorations Inhibition of demineralization adjacent to tooth-colored restorations in primary teeth after 2 in vitro challenges. Effect of Microleakage and Fluoride on Enamel-Dentine Demineralization around Restorations Demineralization of enamel in relation to the fluoride release of materials. In vivo inhibition of demineralization around orthodontic brackets. In situ anticariogenic potential of glass ionomer cement.
PURPOSE Enamel demineralization adjacent to orthodontic brackets is one of the risks associated with orthodontic treatment . Glass ionomer cements have been shown to decrease enamel demineralization adjacent to brackets and b and s but do not exhibit bond strengths comparable to resin composites . The purpose of this in vitro study was to compare a fluoride-releasing resin composite versus a resin-modified glass ionomer cement for inhibition of enamel demineralization surrounding orthodontic brackets . METHODS Forty-five teeth were r and omly assigned to 3 groups of 15 teeth . Fifteen were bonded with Concise ( 3 M ) , a non-fluoride-releasing resin composite ( control ) ; 15 teeth were bonded with Light Bond ( Reliance ) , a fluoride-releasing resin composite ; and 15 teeth were bonded with Fuji Ortho LC ( GC Corporation ) , a resin-modified glass ionomer cement . The teeth were placed in an artificial caries solution to create lesions . Following sectioning of the teeth in a buccolingual direction , polarized light microscopy was utilized to evaluate enamel demineralization adjacent to the orthodontic bracket . The area of the lesion was measured 100 microns from the orthodontic bracket and bonding agent . RESULTS MANOVA ( P < .0001 ) and Duncan 's test ( P < .05 ) indicated the resin-modified glass ionomer cement ( Fuji Ortho LC ) and the fluoride-releasing resin composite ( Light Bond ) had significantly less adjacent enamel demineralization than the non-fluoride-releasing resin composite control . However , there was no significant difference between the resin-modified glass ionomer cement and the fluoride-releasing resin composite . CONCLUSIONS Based on the results of this in vitro study , it can be concluded that Fuji Ortho LC and Light Bond exhibit significant inhibition of adjacent demineralization compared to the non-fluoride-releasing control BACKGROUND The authors examined several restorative material s to evaluate their ability to inhibit demineralization and enhance remineralization of incipient carious lesions on the interproximal enamel of teeth adjacent to those restored with the material s. METHODS Twenty-one subjects in need of a crown on a m and ibular molar and a Class II inlay on an adjacent tooth took part in this six-phase study . Artificial enamel lesions were created and positioned within the interproximal portion of a crown . Lesions were photographed with polarized light microscopy and characterized before and after 30-day intraoral exposures . Each phase included the placement of a new section in the crown model and a new Class II inlay restorative material in the adjacent tooth . RESULTS Results demonstrated that nonfluori date d resin composite , fluori date d resin composite and resin-modified glass ionomer restorative material s , when placed in subjects who brushed with a fluori date d dentifrice , demonstrated significantly ( P < .05 ) less enamel demineralization than the nonfluori date d resin composite control placed in subjects who brushed with a nonfluori date d dentifrice . The resin-modified glass ionomer cement , however , even when brushed with a nonfluori date d dentifrice , exhibited significantly ( P < .05 ) less demineralization than the nonfluori date d resin composite control brushed with a nonfluori date d dentifrice . CONCLUSIONS Resin-modified glass ionomer cement appears to significantly inhibit demineralization of interproximal enamel of teeth adjacent to those restored with the material . CLINICAL IMPLICATION S Resin-modified glass ionomer cement restorations can enhance prevention of enamel demineralization on adjacent teeth OBJECTIVES the purpose of this study was to determine the mineral loss on surrounding enamel restored with glass ionomer cements ( GIC ) after erosive and cariogenic challenges . METHODS Bovine enamel specimens were r and omly assigned into six groups according to the restorative material : G1 - composite resin ; G2 - high viscous GIC ; G3 - resin-modified glass ionomer with nanoparticles ; G4 - encapsulated resin-modified GIC ; G5 - encapsulated high viscous GIC ; G6 - resin-modified GIC . After restorative procedures , half of specimens in each group were su bmi tted to caries challenge using a pH cycling model for 5 days , and the other half were su bmi tted to erosive challenge in citric acid for 10 min . Before and after the challenges , surface Knoop microhardness assessment s were performed and mineral changes were calculated for adjacent enamel at different distances from restorative margin . RESULTS Data were compared for significant differences using two-way ANOVA and Student-Newman-Keuls tests ( p<0.05 ) . Erosive challenge significantly reduced enamel surface hardness , but no significant difference was observed irrespectively restorative material s ( p>0.05 ) . The cariogenic challenge promoted a higher surface hardness loss for the resin-modified GIC ( G4 ) and only for the High viscous GIC ( G2 ) an increase in surface hardness was observed . For enamel analyses , significant differences were observed with respect to the different material s ( p<0.001 ) and distances ( p=0.023 ) . Specimens restored with the composite resin presented higher mineral loss and specimens restored with the conventional high viscous GIC and the encapsulated resin-modified GIC presented the lowest values for mineral loss . CONCLUSION The GICs exerts protective effect only for cariogenic challenge Controversy exists as to whether there is less secondary caries at the margins of glass ionomer restorations compared with other material s that do not release fluoride . This study examined the incidence of secondary caries for three types of restorative material s in Class V restorations in xerostomic patients . The study group consisted of 45 high caries-risk adult patients who had undergone head and neck irradiation for the treatment of cancer . All were substantially xerostomic and in need of at least three restorations in the same arch . Every patient received a restoration with each of the test material s , a conventional glass ionomer ( GI ) , a resin modified glass ionomer ( RMGI ) and a resin composite ( C ) . Patients were instructed in the daily use of a neutral pH sodium fluoride gel in custom trays . Recall appointments were made at 6 , 12 , 18 and 24 months , and the restorations were examined for material loss , marginal integrity and recurrent caries at the restoration margin . Fluoride compliance was determined at each recall period and recorded as the percentage of recommended use during that interval . Patients were categorized at the end of the study as fluoride non-users if their average compliance was 50 % or less . Those with greater than 50 % compliance were categorized as fluoride users . In the latter group , no recurrent caries was found for any of the restorations , whereas a material -dependent incidence of recurrent caries was found in the fluoride non-user group . None of the GI , one RMGI and eight C restorations failed due to recurrent caries . For the fluoride non-user patients , Fishers exact test ( p=0.05 ) showed no statistical difference between GI and RMGI but statistical differences were found among those material s and resin composite at each recall period . Recurrent caries reductions for GI and RMGI relative to C were greater than 80 % in xerostomic patients not using topical fluoride supplementation Previous reports have shown a release of fluoride from glass-ionomer cement ( GIC ) restorations into the oral fluids . Fluoride in the ambient fluids has a caries-preventive effect by enhancing remineralization and inhibiting demineralization of the dental hard tissues . Therefore , the current investigation was undertaken to determine whether GIC fillings could contribute to the remineralization of caries lesions in dentin . Small circular preparations were made in disks of dentin which had incipient caries-like lesions in the remaining tissue . The preparations were filled with amalgam or composite material s ( as controls ) or with GIC . The specimens thus contained a restoration close to a dentinal caries-like lesion . The specimens were placed contralaterally in the buccal surfaces of removable partial dentures and were worn intra-orally by volunteers for a 12-week experimental period , after which the specimens were sectioned and analyzed by microradiography . All specimens with GIC restorations exhibited hypermineralization in the tissue bordering the filling and in the wall of the preparation which had been in contact with the restoration . The ( caries-like ) lesions were remineralized , even under conditions of heavy plaque formation . In contrast , specimens with amalgam or composite restorations showed further extensive demineralization . This study demonstrates a significant remineralization potential exerted by the fluoride-releasing GIC restorative material . Consequently , the choice of the restorative material might be crucial for the occurrence or prevention of recurrent caries around restorations PURPOSE As clinical diagnosis of secondary caries is the most common reason for restoration replacement , fluoride-releasing restorative material s have been developed to address this problem . The purpose s of this study were to verify demineralization inhibition produced by 5 restorative material s su bmi tted to two methods of in vitro cariogenic challenge and verify whether these methods influence material behavior by means of polarized light microscopy and microhardness . METHODS Class V cavities were prepared on buccal surfaces of 100 extracted primary molars and r and omly restored with 1 of the 4 fluoride-releasing material s , Fuji IX , Vitremer , Dyract , Tetric Ceram , and Filtek Z250 as control material ( N=10 ) . Specimens were su bmi tted to in vitro caries induction by two different methods , acid gel immersion , and pH cycling . Teeth su bmi tted to gel were then sectioned and prepared for polarized light microscopy in water , while teeth cycled were prepared for microhardness evaluation . RESULTS Polarized light microscopy : Means of demineralization areas ( microm(2 ) ) differed significantly , depending on the restorative material . Tukey 's test revealed the smallest demineralization areas adjacent to Fuji IX and Vitremer restorations , with no difference between them ( P>.05 ) . The greatest demineralization area mean values were verified using Dyract and Filtek Z250 , without differences between them ( P>.05 ) . Microhardness : Glass ionomer cements ( GICs ) performed better on the area of great cariogenic challenge , closer to the surface , than other material s indicating minor mineral loss during pH cycling . The compomer Dyract presented similar performance to GICs and composite resin Tetric Ceram , but it was better than Filtek Z250 . CONCLUSION The experimental model of caries lesion induction may influence material performance . GICs , however , are superior in preventing in vitro demineralization independently of the method There is no consensus about an association between microleakage and secondary caries , especially considering the presence of fluoride ( F ) at the tooth/restoration interface . Thus , a r and omized , double-blind , crossover study was carried out to evaluate in situ the effect of microleakage on caries around enamel-dentine restorations in the presence of F from dental material s or dentifrice , either alone or in combination . In 4 phases of 14 days each , 14 volunteers wore palatal devices containing dental slabs restored with composite resin ( CR ) or resin-modified glass ionomer cement ( GI ) . Restorations were made without leakage ( L– ) , following the recommended adhesive procedures , or with leakage ( L+ ) , in the absence of adhesive procedures . Plaque-like biofilm ( PLB ) was left to accumulate on the restored slabs , which were exposed extraorally to a 20 % sucrose solution 10 × /day . The volunteers used a non-F ( NF ) or an F ( FD ) dentifrice 3 × /day , depending on the experimental phase . No differences were found between L+ or L– restorations ( p > 0.05 ) . Higher demineralization in both enamel and dentine around CR restorations was observed under NF ( p < 0.05 ) . F concentration was higher in the fluid of PLB exposed to FD or formed onto GI restoration ( p < 0.05 ) . These results suggest that while microleakage does not affect caries development , GI or FD may maintain increased F levels in the PLB , thereby decreasing caries progression PURPOSE To examine the reduction in enamel demineralization provided by fluoride release from a conventional glass-ionomer , a resin-modified glass-ionomer and an experimental fluoride-releasing resin-based composite compared to a conventional resin-based composite control , and to correlate the level of fluoride release with demineralization . MATERIAL S AND METHODS Enamel surfaces of extracted human incisors had a 0.4 mm thick layer of the specified test material carefully placed in a b and across the mid-facial enamel to simulate a cement layer beneath an orthodontic bracket . The top surface of the test material was covered with nail varnish , leaving only the edges of the material exposed to release fluoride . The teeth were additionally covered with nail varnish to within 1 mm of the test material . Each group of teeth was placed into separate volumes of unstirred demineralizing solution at a pH of 4.7 for 4 days . The specimens were sectioned and examined by polarized light microscopy . Lesion areas were measured at distances from 100 - 800 microm away from the test material . Fluoride release for the test material s was measured for periods up to 5 months . RESULTS All of the fluoride-releasing material s demonstrated a statistically significant ( P < 0.05 ) degree of protection of enamel from demineralization compared to the non-fluoride control material . The degree of protection was greatest near the material , but lesion areas increased with distance in an inverse relationship to the amount of fluoride release . Lesions were displaced from the region near the material s and the mean displacement was directly related to amount of fluoride release . The mean lesion areas for each distance decreased with the logarithm of the cumulative fluoride release Demineralization around orthodontic appliances is a problem . Suboptimal oral hygiene , long intervals between appointments , and potentially poor patient cooperation with using fluoride dentifrices and mouth rinses necessitate a compliance-free means of preventing tooth decay . The hypothesis of this study was that fluoride released by glass ionomer cement inhibits the formation of carious lesions around orthodontic brackets in vivo . Brackets were bonded on 2 first premolars in 21 r and omized , consecutively selected patients 11 to 18 years old . Eleven test-group subjects were bonded with fluoride-releasing glass ionomer cement , and 10 control subjects were bonded with composite resin ( no fluoride ) . The teeth were extracted after 4 weeks , sectioned , and evaluated quantitatively by cross-sectional microhardness testing . Fluoride levels in patient saliva were measured by the Taves diffusion method in sample s taken at days 0 ( baseline ) , 1 , 2 , 3 , 7 , 14 , 21 , and 28 to determine whether fluoride from the glass ionomer cement influenced the overall intraoral fluoride levels . The results demonstrated significantly more demineralization around the brackets of the control patients ( P < .01 , Wilcoxon signed rank test ) . For whole-mouth salivary fluoride levels , no significant overall difference between the groups ( P > .05 ) and no noticeable trend within groups ( P > .05 ) were found . These results indicate that using fluoride-releasing glass ionomer cement for bonding orthodontic brackets successfully inhibited caries in vivo . This cariostatic effect was localized to the area around the brackets and was statistically significant after 4 weeks The purpose of this study was to compare the amount of fluoride in plaque formed on glass ionomer cement or composite and to evaluate the effects of fluoride released on growth of cariogenic microflora , fluoride uptake , and secondary caries formation under in situ conditions of a high cariogenic challenge . Ten adult volunteers took part in this crossover study performed in two phases of 28 days . Eighty enamel blocks were r and omly restored with glass ionomer cement ( Chelon-Fil-Espe ) or composite ( Silux ) . During each phase of the study , an acrylic resin appliance , containing four enamel blocks restored with the same material , was constructed for each of the volunteers . During the experimental period , all subjects used fluoride-free dentifrice , refrained from brushing the restored enamel blocks , and immersed the appliances into 20 % sucrose solution eight times a day . Fluoride levels , mutans streptococci , and lactobacilli were assessed in dental plaque . Fluoride uptake and microhardness profiles were determined in enamel around the restorations . Statistical analyses indicated a significantly higher level of fluoride ( p < 0.05 ) and a lower level of mutans streptococci plaque formed on glass ionomer cement . Analysis of variance in a split-plot model indicated that in the enamel around the glass ionomer restoration the fluoride uptake was significantly greater ( p < 0.025 ) and the mineral loss significantly lower ( p < 0.01 ) . The results show that glass ionomer cement presents a broad anticariogenic effect and may be of value in preventing secondary caries , even under conditions of a high caries risk
The evidence suggests that RM-GIC is associated with a higher reduction of demineralization in adjacent hard tooth tissue than composite resin without fluoride .
No difference was found when RM-GIC was compared with fluoride-containing composite resin .
RM-GIC showed efficacy in reducing demineralization .
UNLABELLED The purpose of this systematic review was to quantitatively find out whether resin-modified glass-ionomers ( RM-GIC ) , in comparison to fluoride-containing composite resin and composite resin without fluoride , are associated with a more effective reduction of demineralization in hard tooth tissues under caries challenge .