Post-operative bleaching: effect on microleakage.

The effect of a carbamide peroxide bleaching gel on the microleakage of Class V resin composite restorations with two dentin bonding agents was evaluated using extracted human teeth. Class V cavity preparations were placed at the cementoenamel junction of the facial and lingual surfaces of 20 teeth for a total of 40 preparations. Half of the teeth were restored with Scotchbond 2/Silux Plus and half were restored with Prisma Universal Bond 3/AP.H. Five teeth were randomly selected from each of the two groups and were stored in water at 37 degrees C to serve as controls. The remaining teeth were exposed to a carbamide peroxide gel for three 2-hour periods per day for 9 days. The specimens were stored in distilled water at 37 degrees C except during treatment periods. All teeth were then thermally stressed for 100 cycles. Microleakage was assessed by dye penetration. The results demonstrated that the carbamide peroxide agent adversely affected the marginal seal of both restorative systems.     

Microleakage of bonded amalgam restorations: effect of thermal cycling

This study examined the effect of thermal cycling on the microleakage of bonded amalgam restorations. Three dental amalgam alloys and a gallium alloy were tested with two adhesive resin systems and copal varnish as a control. Class V cavity preparations were prepared on 168 freshly extracted premolars or molars. The preparations were placed parallel to and 1.0 mm occlusal to the cementoenamel junction (CEJ). Four groups of 42 teeth each were treated with one of the following adhesive dentin systems: Bond-It, All-Bond 2/Resinomer or a copal varnish (Copalite). The four groups of 42 teeth each were then restored with one of three dental amalgams: Orosphere Plus, Indiloy, Oralloy or a Gallium alloy (Galloy), resulting in 12 test groups of 14 teeth each. The specimens were stored in double distilled water at 37 degrees C for 24 hours. Final contouring and polishing of the restorations were performed under water spray. Half of the restorations in each group were thermocycled for 3000 cycles (5 degrees C-37 degrees C-55 degrees C-37 degrees C) with a dwell time of 15 sec at each temperature. The other half were stored in double distilled water at 37 degrees C for 24 hours. Then all 168 restorations were stained with dye, sectioned and scored for microleakage. Results showed that the adhesive dentin systems reduced microleakage in amalgam restorations compared to copal varnish only in non-thermocycled specimens. Statistical analysis of the results showed that there was an extremely significant difference (p < 0.001) in microleakage between the non-thermocycled and the thermocycled specimens in all test groups, whereas, there was no significant difference (p > 0.05) among thermocycled specimens. The reduction of microleakage was not significantly different between Bond-It and All-Bond 2/Resinomer in non-thermocycled specimens. Oralloy showed the most microleakage in the non-thermocycled groups when compared to the other alloys using the same adhesive liner.     

Resistance to maxillary premolar fractures after restoration of class II preparations with resin composite or ceromer.

OBJECTIVE: The aim of this study was to evaluate the resistance to fracture of intact and restored human maxillary premolars. METHOD AND MATERIALS: Thirty noncarious human maxillary premolars, divided into three groups of 10, were submitted to mechanical tests to evaluate their resistance to fracture. Group 1 consisted of intact teeth. Teeth in group 2 received mesio-occlusodistal cavity preparations and were restored with direct resin composite restorations. Teeth in group 3 received mesio-occlusodistal cavity preparations and were restored with ceromer inlays placed with the indirect technique. After restoration, teeth were stored at 37 degrees C for 24 hours and then thermocycled for 500 cycles at temperatures of 5 degrees C and 55 degrees C. RESULTS: Statistical analysis revealed that group 3 (178.765 kgf) had a significantly greater maximum rupture load than did group 1 (120.040 kgf). There was no statistically significant difference between groups 1 and 2 or between groups 2 and 3. CONCLUSION: Class II cavity preparations restored with indirect ceromer inlays offered greater resistance to fracture than did intact teeth. The fracture resistance of teeth restored with resin composite was not significantly different from that of either the ceromer or intact teeth.     

Effect of composite resin placement and use of an unfilled resin on the microleakage of two dentin bonding agents

The purpose of this study was to assess, in vitro, the microleakage of Class V restorations using two third generations dentin bonding agents, with a hybrid light polymerized composite resin. One of the bonding agents was of the NPG-PMDM type and the other was a polyhexanide. Restorations were placed in cavities prepared in extracted human premolars using either a bulk or incremental packing technique. The NPG-PMDM-based agent was used with and without an intermediary unfilled resin. The teeth were stored for 1 week at 37 degrees C, thermocycled for 1500 cycles between 55 degrees C, 37 degrees C and 5 degrees C and the restorations examined for leakage using methylene blue dye. The teeth were sectioned through the restorations and the degree of microleakage assessed visually. All groups of restorations showed some degree of leakage at the gingival margin. Statistical analysis showed that there were significant differences in the amounts of leakage (P less than 0.001). There was no difference in leakage between any of the groups that had been restored using the NPG-PMDM system (P greater than 0.05). There was, however, less leakage of the incrementally filled group compared with the bulk-packed group with the polyhexanide agent (P less than 0.05). When the two bonding agents were compared, there was no significant difference in leakage (P greater than 0.05) except for the incrementally-packed polyhexanide and the incrementally-packed NPG-PMDM with unfilled resin (P less than 0.05). Only one specimen in any of the groups leaked at the enamel margin.     

The effect of flowable resin composites as gingival increments on the microleakage of posterior resin composites

Microleakage has been a major concern in restorative dentistry. The curing contraction of composites still presents a problem with controlling microleakage and postoperative sensitivity. This study investigated the effect of flowable materials on gingival microleakage of microhybrid and packable resin composite restorations. Ninety Class II cavities with cervical margins 1 mm below the CEJ were prepared in 45 extracted human premolars. The teeth were randomly divided into three groups (n=15). In each group, one side of each tooth was restored incrementally with respective composites-SureFil, Filtek P60 and Tetric Ceram; whereas, on the other side, flowable materials-Dyract Flow, Filtek Flow or Tetric Flow-were placed respectively as a 1-mm thick gingival increment before the resin composite restoration. The restored teeth were stored for one week in distilled water at 37 degrees C, thermocycled between 5 degrees C and 55 degrees C and immersed in 0.5% basic fuchsin for 24 hours. Dye penetration was evaluated using a stereomicroscope at 10x magnification. The data were analyzed statistically by Kruskal-Wallis analysis of variance and Mann-Whitney U-tests. The effect of flowable increments on reducing the gingival microleakage was found to be statistically significant for all restorative materials tested (p<0.05).     

In vitro microleakage of four tracers with multiple applications to the same tooth

Microleakage testing continues to be undertaken using a variety of techniques and methodologies. This study compared four microleakage tracers to determine if a difference exists in their ability to demonstrate microleakage on a single dental amalgam restorative material by testing in two phases. Class V amalgam restorations were placed on the facial surfaces of 105 extracted human premolars with all margins in enamel. The teeth were stored at 37 degrees C in water for two weeks except during thermocycling for 2500 cycles between 8 degrees C and 48 degrees C. The teeth were prepared for microleakage testing by sealing the external surfaces with nail polish and tinfoil, leaving the restoration and surrounding 1 mm exposed. In the first phase, four groups of 15 teeth were randomly assigned to 0.5% basic fuchsin dye, 2.0% fluorescent dye, 1.5% reactive orange 14 and 45Ca. In the second phase, another three groups of 15 teeth were immersed in 45Ca, then immersed in one of the remaining three tracers. Ridit analysis and Newman-Keuls multiple comparisons were used to compare the groups at a significance level of 0.05. The results indicate that there are differences in observed microleakage between tracers and there is no statistical influence on dye tracers by initial immersion in 45Ca.     

Microleakage of class V resin composite restorations after conventional and Er:YAG laser preparation

This in vitro study compared the microleakage of Class V resin composite restorations at bevelled enamel/composite and dentin/composite interfaces following Er:YAG laser (pre-treatment modalities: laser-etching and/or acid-etching) or conventional preparation and acid-etch, in association with two resin composite formulations and their three-step adhesive system. Class V cavities with conventional bevel produced on the lingual and buccal surfaces of eighty extracted caries- and restoration-free human teeth, were assigned to eight groups: cavities were or Er:YAG-lased and acid-etched (groups 1 and 5); or Er:YAG-lased, laser-etched and acid-etched (groups 2 and 6); or Er:YAG-lased and only laser-etched (groups 3 and 7); or cut by dental drill at high-speed and acid-etched (groups 4 and 8). The specimens were restored with Optibond FL+Herculite XRV (groups 1, 2, 3 and 4) or with Scotchbond MP+Z 100 (groups 5, 6, 7 and 8), stored in distilled water at 37 degrees C for 24 h, thermocycled 1500 times between 5 and 55 degrees C, placed in a 2% aqueous solution of methylene blue for 24 h at 37 degrees C, embedded in resin and sectioned. Microleakage was assessed according to the depth of dye penetration along the restoration. There were statistically significant differences between occlusal and cervical regions for all groups (P<0.01) except for groups 3 and 7. Pair-wise comparison of groups showed that acid-etch is advocated when using resin composite in Er:YAG-lased Class V cavities; the seal at enamel margins in Er:YAG-lased and laser-etched cavities depended on the resin composite formulation and corresponding adhesive (P<0.05).     

The effect of polishing systems on microleakage of tooth coloured restoratives: Part 1. Conventional and resin-modified glass-ionomer cements

The purpose of this in vitro study was to investigate the effect of polishing systems on the microleakage of conventional and resin-modified glass-ionomer cements. Class V cavities were prepared at the cemento-enamel junction of 80 freshly extracted posterior teeth. The prepared teeth were randomly divided into two groups and restored with conventional or resin-modified glass-ionomer cements. The restored teeth were stored in distilled water at 37 degrees C for 1 week after removal of excess restorative with diamond finishing burs. The restored teeth were then divided into four groups of 10 and finished and polished using the following systems: Two Striper MFS; Sof-Lex XT; Enhance Composite Finishing and Polishing System; Shofu Composite Finishing Kit. The finished restorations were subjected to dye penetration testing. Results showed that the microleakage at dentin margins of conventional glass-ionomer cements and enamel margins of resin-modified glass-ionomer cements are significantly affected by the different polishing systems.     

The effect of polishing systems on microleakage of tooth-coloured restoratives. Part 2: composite and polyacid-modified composite resins

The purpose of this in vitro study was to investigate the effect of polishing systems on the microleakage of composite and polyacid-modified composite resins. Class V cavities were prepared at the cemento-enamel junction of 80 freshly extracted posterior teeth. The prepared teeth were randomly divided into two groups and restored with conventional or polyacid-modified composite resins. The restored teeth were stored in distilled water at 37 degrees C for 1 week after removal of excess restorative with diamond finishing burs. The restored teeth were then divided into four groups of ten and finished/polished using the following systems: Two Striper micron finishing system (MFS), Sof-Lex XT (Sof-Lex), Enhance composite finishing and polishing system (Enhance), and Shofu composite finishing kit (Shofu). The finished restorations were subjected to dye penetration testing. Results showed that the microleakage resistance at both enamel and dentin margins of composite and polyacid-modified composite resins are not significantly affected by the different polishing systems.     

The effect of pulse activation on microleakage of a 'packable' composite resin and two 'ormocers'

The purpose of the study was to examine the effect of pulse polymerization on microleakage of one packable composite resin and two organically modified ceramics (ormocers), within a high C-factor preparation. Class-V cavity preparations with occlusal margins in enamel and gingival margins in dentin were prepared on 60 freshly extracted premolars or molars. Teeth were randomly assigned to 12 experimental groups (five teeth each) representing the different restorative systems, mode of polymerization and thermal cycling test. Three groups of 20 teeth each were restored with one of the following restorative systems: Scotch bond 1/Filtek P 60, Admira bond/Admira, Etch&Prime 3.0/Definite. 10 restorations of each restorative system (two experimental groups) were conventionally polymerized, whereas the other 10 restorations were polymerized with a pulse program. The specimens were stored in double-distilled water at 37 degrees C for 24 h. Ten restorations from each restorative system (30 restorations, half of the specimens) were thermocycled, the other 30 restorations were kept in double-distilled water at 37 degrees C for 24 h. Then all 60 restorations stained with dye, sectioned and scored for microleakage. Results showed that there were no significant differences (P > 0.05) among the materials with respect to microleakage scores. The experimental groups that were conventionally polymerized revealed significantly more microleakage (P < 0.05) after thermal cycling than all the other groups. The gingival microleakage was significantly more (P < 0.05) than occlusal in conventionally polymerized, thermocycled experimental groups.     

In vitro microleakage of composite restorations after nonvital bleaching.

OBJECTIVE: After bleaching treatment, esthetic restorations often need to be replaced due to color changes. Some papers have shown alterations in the bond of adhesive restorations to bleached teeth. The purpose of this study was to evaluate tooth and resin composite adhesion when submitted to nonvital dental bleaching. METHOD AND MATERIALS: One hundred and twenty bovine teeth were assigned to 3 groups (n = 40); paste of sodium perborate and water; 37% carbamide peroxide gel; and no bleaching (control). After 3 weeks of continuous bleaching treatment, standardized Class V cavities were prepared at the cementoenamel junction and restored with Single Bond adhesive system and Z100 resin composite. The samples were thermocycled 1,500 times (5 +/- 1/55 +/- 1 degrees C) with a 1-minute dwell time. Then, they were immersed in a 2% methylene blue solution (pH 7) for 4 hours, sectioned, and analyzed by stereomicroscopy. Microleakage analyses were done, using scores from 0 to 4, considering leakage on the incisal wall (enamel) and the cervical wall (dentin). Data were analyzed by Kruskal-Wallis and Mann-Whitney tests (alpha = 0.05). RESULTS: The results showed that sodium perborate and carbamide peroxide gel significantly increase the microleakage in Class V resin composite restorations to dentin but not to enamel margins. CONCLUSION: The risk of microleakage in dentin margins is increased soon after bleaching treatment.     

Effect of dentin deproteinization on microleakage of Class V composite restorations

The role of the collagen fibers in dentin adhesion has not clearly been established. Therefore, this laboratory study evaluated the microleakage at resin-dentin and resin-enamel interfaces of Class V composite restorations after etching enamel and dentin with phosphoric acid (H3PO4) or after etching with H3PO4 followed by deproteinization with 5% sodium hypochlorite (NaOCl) to prevent the formation of a hybrid layer. Ten extracted human molars were used to prepare standardized Class V cavities on both buccal and lingual surfaces. The teeth were randomly divided in two groups: 1) Class V cavities that were etched with H3PO4 for 15 seconds; b) Class V cavities that were etched with H3PO4 for 15 seconds followed by collagen removal with 5% NaOCl for two minutes. The cavities were restored using the Prime & Bond 2.1 bonding system and TPH resin composite. The specimens were stored in water for 24 hours at 37 degrees C and thermocycled 500 times between water baths kept at 5 degrees C and 55 degrees C. After thermocycling, specimens were immersed in a 0.5% aqueous solution of basic fuchsin for 24 hours. Three longitudinal sections of each restoration were obtained and examined with a stereomicroscope for qualitative evaluation of microleakage. The data were statistically analyzed by Mann-Whitney U and Wilcoxon matched pairs signed ranked tests. Extra specimens were analyzed with the scanning electron microscope (SEM). Occlusal margins (enamel margins) resulted in statistical lower degree of leakage than gingival margins (dentin/cementum margins) in both treatment groups. For each type of margin, there were no statistically significant differences between the etched and the etched and deproteinized groups. Under the SEM, occlusal surfaces showed no detachment between enamel and dentin, while dentin/cementum resulted in gap formation.     

Microleakage of Class V resin composite restorations placed with self-etching adhesives

STATEMENT OF PROBLEM: Although they are widely available, there is insufficient information about the capability of self-etching adhesives in sealing the margins of resin composite restorations. PURPOSE: The purpose of this study was to compare the in vitro microleakage of Class V resin composite restorations placed using a strong pH self-etching adhesive, an intermediate pH self-etching adhesive, and an adhesive with a separate etchant and primer. MATERIAL AND METHODS: Class V resin composite restorations (n = 8) were placed in prepared cavities in extracted human third molars using 2 self-etching dentin adhesives, Prompt L-Pop (Strong pH) or One-Up Bond F (Intermediate pH), and an adhesive with a separate etchant and primer, ScotchBond Multi-Purpose. The restored teeth received 1000 thermal cycles between 5 degrees C and 55 degrees C water baths with a 1-minute dwell time and were subsequently subjected to a methylene blue dye challenge and sectioned. The sectioned specimens were scored as demonstrating none, slight, or severe leakage (n=16). Ranked data were analyzed using a 1-way analysis of variance at a 5% confidence level. RESULTS: The only leakage observed was along gingival margins, with an incidence of 31% for Prompt L-Pop and One-Up Bond F, and 50% for ScotchBond Multi-Purpose. CONCLUSION: No significant differences in marginal leakage were found among the adhesives tested.     

Microleakage of Class V restorations using two different compomer systems: an in vitro study

This study compared the marginal microleakage of Class V cavities restored with Dyract-AP and F2000. Forty Class V cavity preparations were performed on extracted human teeth. As a negative control, twenty teeth were used without Class V preparations. The apical foramina of the teeth were sealed with a layer of varnish and amalgam restorations. Class V cavity preparations with occlusal margins in enamel, and gingival margins in cementum or dentin that measured approximately three millimeters in width (gingival-occlusal) and length (mesial-distal), were prepared on the buccal surface of the teeth. Samples were divided randomly into 2 groups of 15, and restored per manufacturer's instructions using experimental primer/conditioner (PCC, D/C) and Single Bond Adhesive (3M). All restorations were polished with an abrasive finishing kit. After storage in 37 degrees C water for 24 hours, all specimens were thermocycled between 5 degrees C and 55 degrees C for 500 cycles with a 30-second dwell time, followed by immersion in 0.2% basic fucsine for 24 hours. Teeth were then embedded in cold cure acrylic resin, sectioned longitudinally, and the dye penetration at the enamel and cementum margins were scored at 30x magnification. Evaluations were rated from 0 to 3 (0 = no leakage; 1 = dye penetration up to one-half of the preparation depth; 2 = dye penetration more than one-half preparation depth, but less than the axial wall; 3 = dye penetration along the axial wall). Both F-2000 and Dyract-AP indicated no leakage in the enamel margins. Dyract-AP showed no leakage at either the enamel or dentin margins. Fisher's Exact Test revealed that this difference in dentin margins was statistically significant (p < 0.05). Under the given conditions, Dyract-AP and F-2000 demonstrated resistance to microleakage in enamel, and showed Dyract-AP to be more resistant to microleakage in dentin than F-2000.     

The effects of high concentration tooth whitening bleaches on microleakage of Class V composite restorations

OBJECTIVE: To explore the effects of high-concentration hydrogen peroxide bleaching agents on the microleakage of composite restorations. METHODS: In 60 extracted human molars, Class V restorations were prepared with Scotchbond 1/Filtek Z250 composite. Teeth were randomly divided into four groups: (1) no bleaching; (2) bleaching with 14% hydrogen peroxide gel from Crest Whitestrips; (3) bleaching with 20% carbamide peroxide gel from Opalescence PF 20; and (4) bleaching with 38% hydrogen peroxide gel Opalescence Xtra Boost. Bleaching procedures were carried out at 37 degrees C for 21 days/42 hours (2); seven days/42 hours (3); one day/45 minutes (4). Varnish was applied on the apical portion of the teeth only, excluding the restoration, prior to immersion in a 0.1% rhodamin-B-isothiocyanate solution for 24 hours at 37 degrees C. After rinsing, specimens were embedded in methacrylate blocks, and sectioned with a water-cooled microtome with three restoration cuts positioned centrally parallel to the long axis of the tooth. Microleakage was evaluated at the occlusal margins of the Class V restorations using a stereo microscope, separate for dentin and enamel margins. RESULTS: Over 90% of enamel margins exhibited no microleakage following cycling. Bleaching agents had almost no effect on numerical averages. Eighty-eight percent of the dentin margins were free of microleakage for the non-treated control group. Bleaching treatments collectively had slight numerical reductions to around 80%. The statistical evaluation (Kruskal-Wallis-test) showed no significant difference in microleakage between groups for enamel or dentin. CONCLUSION: Bleaching with the materials tested had no influence on microleakage of Filtek Z250 composite bonded with Scotchbond 1.     

Comparison of microleakage of experimental and selected commercially available bonding system

The microleakages of composite restorations bonded with two commercial and two experimental systems were observed. A high-viscosity condensable composite and a low-viscosity composite were used as the restorative materials. The bonding systems used were two widely accepted commercial brands and two experimental systems, one containing ferric oxalate and the other aluminum oxalate. Restorations were placed in cavities prepared in extracted human teeth and treated with the various bonding systems. These restorations were stored in 37 degrees C water for 24 hours and then polished. The restored teeth were subjected to seven days of thermocycling (5 degrees C-55 degrees C for 540 cycles per day). Microleakage was detected and scored from 0-4 according to the degree of stain penetration. The experimental systems had lower scores than the commercial systems. The high-viscosity composite restorations had microleakage scores higher than those of the lower-viscosity composite restorations.     

Fracture resistance of teeth restored with the bonded amalgam technique

This study evaluated the fracture resistance of maxillary premolars with MOD Class II cavity preparations restored with silver amalgam (G1), Scotchbond Multi Purpose Plus and silver amalgam (G2) and Panavia F and silver amalgam (G3). After the restorations were made, the specimens were stored at 37 degrees C for 24 hours at 100% humidity and submitted to the compression test. Statistical analysis of the data (ANOVA and Tukey Test) revealed no significant differences among the three groups that were studied.     

漂白剂对玻璃离子水门汀类材料充填Ⅴ类洞边缘微渗漏的影响

目的评估漂白凝胶和洁白牙贴对3种不同的玻璃离子水门汀类材料边缘微渗漏的影响。方法在45颗离体健康前磨牙的颊舌侧制备Ⅴ类洞,随机分为A、B、C组,分别使用加强型玻璃离子水门汀KetacTM Molar Easymix、复合体F2000、复合体Dyract AP充填,每个大组再分为3个亚组,第1组和第2组分别使用质量分数14％过氧化氢（HP）洁白牙贴和10％过氧化脲（CP）凝胶进行漂白,第3组为对照组。所有样本置入37 ℃蒸馏水中保存7 d后冷热循环500次,然后进行漂白。漂白21 d后置于碱性品红溶液中染色24 h,沿牙体长轴通过充填体中央颊舌向剖开牙齿,体视显微镜下观察并测量染料渗入窝洞壁的深度。结果2种漂白方式对充填体边缘微渗漏的影响没有明显差异（P>0.05）;与对照组相比,2种漂白方式对B、C组的微渗漏均没有产生明显影响（P>0.05）,但均可使A组的微渗漏增加（P<0.05）。结论10％CP凝胶和14％HP洁白牙贴对充填体边缘微渗漏的影响无明显差异;漂白不会影响复合体的微渗漏,但会增加加强型玻璃离子水门汀的微渗漏。     

The effect of fiber placement or flowable resin lining on microleakage in Class II adhesive restorations

PURPOSE: The aim of this in vitro study was to evaluate the effect of two fibers (polyethylene or glass) and a flowable resin liner on microleakage in Class II adhesive restorations. MATERIALS AND METHODS: Class II adhesive cavities were prepared on mesial and distal surfaces of 40 extracted sound human molars. The cavity margins were below or above the CEJ. The teeth were randomly divided into four groups according to the restoration technique: group 1: restored with a resin composite (AP-X, Kuraray) in bulk after SE Bond (Kuraray) treatment; group 2: flowable resin liner (Protect Liner F, Kuraray) was used before composite restoration; in group 3, a polyethylene fiber (Ribbond) and in group 4, a glass fiber (everStick NET, StickTech) was placed into the bed of flowable resin before composite restoration. Samples were finished, stored in distilled water for 7 days at room temperature, and then thermocycled for 300 cycles between 5 degrees C and 55 degrees C. After sealing the apices, the teeth were varnished within 1 mm of the margins and placed in 0.5% basic fuchsin dye for 24 h at 37 degrees C. After rinsing, the teeth were sectioned longitudinally through the restorations and microleakage was evaluated with a stereomicroscope. Marginal penetration was scored on a 0 to 4 scale, and the data were statistically analyzed using Kruskal-Wallis and the Mann-Whitney U-test. RESULTS: Flowable resin, everStick NET, and Ribbond THM used in combination with flowable resin significantly reduced leakage at occlusal margins in cavities with enamel margins (p < 0.05). When the leakage values on cervical dentin margins were evaluated, there was no statistically significant difference among the tested groups (p > 0.05). CONCLUSION: Use of flowable composite alone or in combination with polyethylene or glass fibers reduces occlusal leakage in Class II adhesive cavities with enamel margins.     

Effects of finishing/polishing techniques on microleakage of resin-modified glass ilonomer cement restorations

This study investigated the effect of finishing/polishing techniques on the microleakage of resin-modified glass ionomer restorations. Class V preparations were made on the buccal and lingual/palatal surfaces of freshly extracted teeth. The cavities on each tooth were restored with Fuji II LC (FT [GC]) and Photac-Fil Quick (PF [3M-ESPE]) according to manufacturers' instructions. Immediately after light-polymerization, gross finishing was done with eight-fluted tungsten carbide burs. The teeth were then randomly divided into four groups and finishing/polishing was done with one of the following systems: (a) Robot Carbides (RC); (b) Super-Snap system (SS); (c) OneGloss (OG) and (d) CompoSite Polishers (CS). The sample size for each material-finishing/polishing system combination was eight. After finishing/polishing, the teeth were stored in distilled water at 37 degrees C for one week. The root apices were then sealed with acrylic and two coats of varnish was applied 1 mm beyond the restoration margins. The teeth were subsequently subjected to dye penetration testing (0.5% basic fuchsin), sectioned and scored. Data was analyzed using Kruskal-Wallis and Mann-Whitney U tests at a significance level of 0.05. Results of statistical analysis were as follows: Enamel margins: PF-OG相似文献