不同邻面抛光方法对牙釉质表面粗糙度及表面形貌的影响

目的：评价4种邻面抛光方法对邻面釉质表面粗糙度及显微形貌的影响,为邻面抛光方法的选择提供依据。方法：选择21颗离体牙前磨牙,沿颊舌面中线纵剖后获得邻面釉质试件42枚,再用自凝塑料包埋,暴露邻面釉质,用浮石粉抛光,并超声清洗。将42个试样均分为6组,分别作如下处理：A组空白对照,不做处理;B组：阴性对照,采用标准金刚砂车针切磨触点及其周围釉质,切磨后不抛光;其余4组为实验组,经标准金刚砂车针切磨后分别采用以下方法抛光：C组：极细粒度金刚砂车针抛光;D组：裂钻抛光;E组：矽粒子抛光;F组：彩虹抛光条抛光。之后用粗糙度仪测定釉面粗糙度,并进行扫描电镜观察。结果：标准金刚砂车针切磨后粗糙度大幅度增加（P〈0.05）,釉质表面发生明显条形凹陷性缺损;经4种方法抛光后,釉质表面粗糙度均有显著下降（P〈0.05）,显微形貌均较阴性组光滑,其中矽粒子抛光组可达到较空白对照组更为光滑的表面。结论：实验涉及的4种不同邻面抛光方法均有助于降低釉质切磨区域的表面粗糙度,但抛光效果存在差异;采用矽粒子抛光可完全抵消牙体预备时旋转器械对邻牙邻面的切磨作用,获得最为光滑的釉质表面。     

Surface geometry of three packable and one hybrid composite after polishing

This study evaluated the surface quality of four composite materials after polishing with six different polishing techniques. Eighty specimens were made using three packable composites (Definite/Degussa, SureFil/ Dentsply and Solitaire/Heraeus-Kulzer) and one hybrid composite (Herculite XRV/Kerr). Five specimens of each material were polished using flexible Sof-Lex discs. The remaining 75 specimens of each composite were prepared using three finishing protocols: a single 30 microm diamond (n = 25), two finishing diamonds (30/20 microm; n = 25) and a 30 microm diamond followed by a tungsten carbide finishing bur (n = 25). Final polishing of each of the three finishing groups was accomplished with SuperBuff, Diafix-oral, OneGloss, Astropol and HaWe Composite Polishers (n = 5, each). Surface roughness was evaluated quantitatively by laser-stylus profilometry. Average roughness (R(a)) was calculated; statistical analysis of the data was performed with two-way ANOVA and Scheffé post-hoc tests. The polished surfaces were examined qualitatively by SEM. The results showed significant effects on surface roughness from the different composites (p = 0.011) and polishing systems (p < 0.001). After polishing, the Solitaire surfaces (R(a) = 0.72 microm) were smoother than Definite (R(a) = 0.87 microm) and SureFil (R(a) = 0.89 microm) and significantly smoother than Herculite (R(a) = 0.92 microm; p = 0.011). Three of the polishing methods (SuperBuff, Diafix-oral and Astropol) achieved lower R(a)-values than Sof-Lex discs. The polishing quality of the one-step systems SuperBuff and Diafix-oral was strongly affected by the initial finishing protocol.     

Three-dimensional surface profile analysis of different types of flowable restorative resins following different finishing protocols

AIM: The aim of this study was to investigate the surface roughness of different types of flowable restorative resins and compare the effectiveness of diamond finishing burs followed by aluminum oxide discs with aluminum oxide discs alone in producing smooth surfaces. METHODS AND MATERIALS: Twenty-four specimens (10 mm X 2 mm) for each flowable resin (flowable microhybrid composite, flowable liquid microhybrid composite, flowable compomer, and flowable ormocer) were fabricated in an acrylic mold and randomly assigned to three groups. In group I samples were left undisturbed after the removal of a Mylar strip (control). In group II samples were polished with diamond finishing burs, followed by aluminum oxide discs. In group III samples were finished with only aluminum oxide discs. The mean surface roughness (Ra, microm) was determined with 3-D non-contact interferometry. Data were subjected to one way analysis of variance (ANOVA), and post hoc comparison was accomplished using Tukey's HSD. RESULTS: Although significant differences in surface roughness (Ra) values were observed among the materials using a Mylar strip (control), no significant differences between restorative materials were found when all finishing/polishing methods were combined. For all flowable restorative resins tested, the Mylar strip produced surfaces smoother than those produced by a diamond finishing bur followed by a disc or by using discs alone. Surface roughness values were statistically similar for a diamond finishing bur followed by a disc and for disc treated surfaces within each material except for Dyract Flow, a flowable compomer. CONCLUSION: Although the surface roughness of flowable restorative resins differs among the types, this difference can be overcome with different finishing/polishing methods.     

Surface geometry of four nanofiller and one hybrid composite after one-step and multiple-step polishing

This study assessed the surface quality of four nanoparticle composites and one hybrid composite after polishing with three different techniques. Nanocomposites Premise (KerrHawe), Tetric EvoCeram (Ivoclar Vivadent), Filtek Supreme (3M ESPE) and Ceram X Duo (Dentsply) and the hybrid composite Herculite XRV (KerrHawe) were selected. Sixty specimens 7x7 mm each were fabricated from these materials. After light curing, the specimens were treated with 600 grit sandpaper discs. Fifteen specimens of each composite were polished using flexible Sof-Lex discs (3M ESPE). The remaining 45 specimens of each material were prepared with three finishing protocols: a single 30 microm diamond (n=15), a sequence of a 30 microm and a 20 microm diamond (n=15) and a 30 microm diamond followed by a tungsten carbide finishing bur (n=15). Each series of 15 specimens was then subdivided into three groups of five and polished with the Astropol system (Ivoclar Vivadent), OptiShine brushes (KerrHawe) and the Enhance/PoGo system (Dentsply). Quantitative evaluation of surface roughness was done with the help of optical laser stylus profilometry. Average roughness (Ra) was calculated, and the effect of the materials, the finishing regimen and the polishing methods on surface roughness were analyzed by three-way and two-way Anova and Scheffé post-hoc tests. Qualitative evaluation of the surfaces was done with the help of scanning electron microscopy (PSEM 500, Phlipps). Photomicrographs were assessed with respect to surface quality in four gradings. Surface roughness after polishing was significantly influenced by three factors: composite material (p < 0.001), finishing protocol (p < 0.001) and polishing method (p < 0.001). There were strong interactions between the finishing and polishing methods (p < 0.001). Two of the nanocomposites were significantly smoother (p < or = 0.001), while the other two had a surface quality similar to that of a hybrid composite. Astropol achieved the lowest average roughness on all composites. Except for a combination of a 30 microm diamond and OptiShine brushes, which caused severe roughness, all the polishing methods produced surfaces that were significantly smoother than using the Sof-Lex discs.     

Surface roughness of resin composite prepared by single-use and multi-use diamonds

PURPOSE: To compare the surface roughness of a resin composite caused by two 30- and 40-microm, multi-use finishing diamonds with two 30- and 40-microm, single-use finishing diamonds of comparable grit size before and after steam sterilization. METHODS: Resin composite specimens 6 mm in diameter and 3 mm in depth were light cured. Surface roughness (Ra, microm) of surfaces formed by Mylar, after finishing with a bur, and after polishing with fine and superfine aluminum oxide disks was measured for the as-received and after sterilization conditions with a surface profilometer. RESULTS: Ra of Mylar surfaces (baseline) ranged from 0.02-0.05 microm. Ra of surfaces prepared with 30-microm diamond burs ranged from 1.42-1.90 microm. Ra of surfaces prepared with 40-microm diamond burs ranged from 2.22-2.42 microm. Ra of surfaces polished sequentially with fine and superfine aluminum oxide disks ranged from 0.07-0.11 microm in the as-received condition and from 0.12-0.14 microm in the sterilized condition. Sterilization and reuse of all types of diamond finishing burs resulted in equal or rougher resin composite surfaces after final polish when compared to final polish surfaces that were initially finished with as-received diamonds. CLINICAL SIGNIFICANCE: Surface roughness of a resin composite prepared with single- and multi-use diamond finishing burs was equivalent when compared at the final polish.     

Finishing and polishing of indirect composite and ceramic inlays in-vivo: occlusal surfaces

This study evaluated occlusal margins and surfaces of composite and ceramic inlays after finishing and polishing in vivo. Eighty Class II cavities surrounded by enamel were prepared by two experienced dentists. Forty cavities were restored with indirect microhybrid composite inlays (Tetric), the balance were treated with heat-pressed glass ceramic inlays (IPS Empress). Using a rubber dam, the inlays were inserted adhesively with a dual curing composite of high viscosity (Variolink Ultra). Finishing was performed with the sequence of a 30 microm and 20 microm diamond (finishing method FM 1) or a 30 microm diamond followed by a tungsten carbide finishing bur (FM 2). The composite inlays were divided into four groups of 10 that were finished and polished according to the following protocol: (A) FM 2/Diafix-oral, (B) FM 2/MPS gel, (C) FM 1/Diafix-oral, (D) FM 1/MPS gel. Ten ceramic inlays each were treated as follows: (E) FM 2/MPS gel, (F) FM 1/MPS gel, (G) FM 2/ Diamond polisher, (H) FM 1/Ceramiste silicon polishers. After polishing, replicas of the restorations were fabricated. The replicas were examined by SEM with respect to margin quality (portion of continuous margins, overhangs, submargination and marginal imperfections). Furthermore, surface properties were evaluated qualitatively, which included assessing roundness of the contours in three grades (smooth rounding, few edged contours or predominantly edged contours) and evaluation of the surface roughness (smooth and homogeneous surface, minor roughness or severe roughness). Quantitative analysis of the occlusal composite and ceramic inlay margins showed that 52.2%-84.6% were rated as continuous, 0%-14.0% were characterized by overhangs and 0.7%-10.8% by submargination. A portion of 4.9%-18.1% margins revealed imperfections. The amount of marginal gap formation was negligible. Composite and ceramic inlays showed a similar behavior with respect to marginal quality after finishing and polishing. Overall, there were no significant differences among the four methods applied to composite and the four methods used on ceramic inlays with respect to margin quality. The use of a 30 microm diamond followed by a tungsten carbide bur on composite and ceramic inlays resulted in a significantly larger portion of continuous margins compared to finishing with two diamonds (p=0.049). Qualitative evaluation of composite and ceramic inlays revealed that 50%-80% of the occlusal surfaces were characterized by few edged contours and 10%-50% by smooth rounding. With respect to roughness, smooth surfaces prevailed both on composite (67.5%-80.0%) and ceramic inlays (64.5%-77.3%). Overall, no significant differences were detectable between the methods for finishing and polishing composite inlays and the methods applied to ceramic restorations with respect to roundness of contours and surface roughness.     

Surface roughness and wettability of enamel and dentine surfaces prepared with different dental burs

The aim of dental adhesive restorations is to produce a long lasting union between the restoration and the tooth structure. This bond depends on many variables including the geometry of the preparation and the type of bonding agent or luting cement. It is therefore suggested that the topography of the tooth surface may influence the wettability and the bonding quality of adhesive systems. This study measured the surface roughness and wettability of enamel and dentine after preparation with different dental burs. The mesial and distal surfaces of 15 extracted sound human premolar teeth were prepared with a tungsten carbide crown bur, a diamond bur and a tungsten carbide finishing bur and finished in enamel or dentin, respectively. The prepared surfaces were analysed with a surface profilometer and scanning electron microscopy (SEM). The contact angle of distilled water on each of the prepared surfaces was used as the measure of wettability. The differences in average surface roughness (Ra) were significant between the rotary instrument groups, as revealed by a two-way ANOVA test. No differences were detected between enamel and dentine surfaces prepared with the same type of dental bur. The smoothest surfaces were those completed with tungsten carbide finishing burs. The diamond bur preparations were intermediate in the roughness assessment and the tungsten carbide crown burs gave the roughest surfaces. There were no significant differences in the contact angle measurements for the various groups. It was concluded that the surface roughness of enamel and dentine prepared by different rotary instruments had no significant influence on the wettability of distilled water on these surfaces.     

Comparative evaluation of four finishing systems on one ceramic surface

PURPOSE: Occlusal adjustment of ceramic restorations may be necessary to correct interferences. A rough surface may abrade opposing tooth or restorative materials, thereby increasing plaque accumulation. The aim of this study was to compare the effect of four finishing systems and diamond paste on ceramic roughness. MATERIALS AND METHODS: Forty ceramic disks were distributed into four randomized groups. The initial roughness of all samples was increased with a diamond bur. Samples in group 1 were finished with white silicon and black rubber; group 2 samples were finished with Shofu rubbers; group 3 samples were finished with diamond burs; and group 4 samples were finished with Sof-Lex disks. All samples were then polished by Yeti diamond paste. The surfaces were characterized by means of a surface roughness analyzer. The parameters Ra, Rpm, and Rz were determined. Four roughness recordings were made before and after diamond bur finishing, and before and after Yeti paste polishing. ANOVA was used to test the significance of differences between groups at each stage of the procedures. RESULTS: All four methods reduced the average roughness of the samples. The most effective system was Sof-Lex disks. Diamond paste can round the profile shape and reduce the height of maximum peaks of the surface, but it may not improve the average roughness. CONCLUSION: All systems tested reduced the roughness of ceramic samples, but the Sof-Lex disk finishing system may be more efficient than other methods. The efficiency of the diamond paste is not clear.     

Effectiveness of diamond-impregnated felt wheels for polishing a hybrid composite

The effectiveness of diamond-impregnated felt wheels for polishing the surfaces of a fine-particle hybrid composite was studied in relation to different finishing methods. Standardised composite specimens were finished with one or a series of two or three finishing diamonds (particle size 30, 15 and 8 μm), one or two tungsten carbide finishing burs (12- and 30-fluted) or with a finishing diamond followed by a tungsten carbide bur. The final polishing of all specimens was done with the diamond-impregnated felt wheel Diafix α. Treatment with Sof-Lex discs after the use of a finishing diamond served as a polishing standard for comparison. Evaluation of the final surfaces was done with profilometry and by scanning electron microscopy. The profilometric results showed that the type of pretreatment was decisive for the quality of the final polishing. Nearly all surfaces polished by the diamond-impregnated felt wheels were smoother than those treated by the flexible discs (P<0.01). The lowest roughness data were recorded following a pretreatment with a finishing diamond and a tungsten carbide finishing bur. After appropriate pretreatment, the hybrid composite surface was sufficiently polished with the diamond-impregnated felt wheels.     

Polishing methods of an alumina-reinforced feldspar ceramic

The purpose of this study was to test the hypothesis that mechanical polishing methods of ceramic surfaces allow similar superficial roughness to that of glazed surfaces. Twenty-five Vitadur Alpha ceramic discs (5 mm x 2 mm) were prepared according to the manufacturer's specifications. All specimens were glazed and randomly assigned to 5 groups (n=5), according to finishing and polishing protocols: G1: glazed (control); G2: diamond bur finishing; G3: G2 + silicon rubber tip polishing; G4: G3 + felt disc/diamond polishing paste; G5: G3 + felt disc impregnated with fine-particle diamond paste. Next, surface roughness means (Ra - microm) were calculated. Qualitative analysis was made by scanning electron microscopy. Surface roughness data were submitted to ANOVA and Tukey's test at 5% significance level. G1 and G4 were statistically similar (p>0.05). G2 presented the highest roughness means (p<0.05) followed by groups G3, G5, G4 and G1 in a decreasing order. The hypothesis was partially confirmed as only the mechanical polishing (G4) produced similar superficial roughness to that of surface glazing, although finishing and polishing are technically critical procedures.     

Enamel surfaces following interproximal reduction with different methods

OBJECTIVE: To assess the surface roughness resulting after application of currently available interproximal polishing. MATERIALS AND METHODS: The analysis was carried out by means of digital subtraction radiography, profilometry, and scanning electron microscopy. The roughness of natural untreated enamel served as the reference. Five enamel reduction methods were tested (Profin, New Metal Strips, O-Drive D30, Air Rotor, and the Ortho-Strips) and were applied in accordance with their manufacturers' recommendations. Fifty-five teeth were treated by randomly chosen methods, all of which were applied by one person. One proximal surface was only ground and left unpolished while the other received the finishing and polish recommended by the manufacturer. RESULTS: Loss of tooth substance, as measured by subtraction radiography, was significantly lower (P < .05) for the group treated with Ortho-Strips. Profilometric analysis of enamel roughness showed that the use of Ortho-Strips, O-Drive D30, and New Metal Strips in the grinding mode produced equally rough surfaces (P > .05). The Air Rotor and Profin system in the grinding mode produced the significantly (P < .05) roughest surfaces. A significant (P < .05) reduction of the mean roughness values was registered in all groups when treatment was followed by polishing. The Profin system and Ortho-Strips achieved the significantly smoothest surfaces (P < .05) with polishing. CONCLUSIONS: In general, interproximal enamel reduction should be followed by thorough polishing. Furthermore, oscillating systems seem to be advantageous.     

The effect of polishing on surface roughness of tissue conditioners

PURPOSE: Surface roughness can affect microbial colonization of long-term denture liners, alloys, and denture acrylic. The purpose of the present study was to examine the effect of finishing and polishing procedures on surface roughness of 4 temporary resilient denture liners (tissue conditioners). MATERIALS AND METHODS: Mean surface roughness was measured for 4 materials (Lynal, Visco-gel, Coe-Soft, and Functional Impression Tissue Toner [FITT]) finished in 4 ways: unfinished (control); polished; reduced, unpolished; and reduced, polished. Samples were allowed to polymerize at 37 degrees C for 24 hours, and the surface roughness was measured using a Mitutoyo Surftest 212. RESULTS: Mean surface roughness ranged from 1.8 +/- 0.8 microns for polished Lynal to 7.8 +/- 1.1 microns for reduced, unpolished FITT. All polished samples were smoother than unpolished samples (including controls), whether or not the samples were reduced with a bur. CONCLUSION: Polished samples of tissue conditioning material had lower mean surface roughness measurements than control or reduced, unpolished samples at the 95% level of confidence. There was no difference in mean surface roughness measurements of control samples and unpolished samples reduced with a bur at the 95% level of confidence. Mean surface roughness differed significantly between the materials tested.     

Enamel loss associated with orthodontic adhesive removal on teeth with white spot lesions: an in vitro study.

Teeth with white spot lesions (WSL) might be more prone to enamel loss during bracket debonding. This in vitro study compared enamel loss from teeth with (n = 14) and without (n = 14) WSL after polishing with low-speed finishing burs or disks (Sof-Lex, 3M ESPE, St Paul, Minn). Debonded surfaces were analyzed with a contact stylus profilometer, and digitized data were compared with baseline readings by using AnSur NT software (Regents, University of Minnesota, Minneapolis, Minn). Specimen surfaces were also examined with a scanning electron microscope. Two-way analysis of variance was performed to analyze the data. In teeth without WSL, the volume losses were 0.16 mm(3) for the bur group and 0.10 mm(3) for the disk group; the mean maximum depths were 47.7 microm for the bur group and 54.3 microm for the disk group. In teeth with WSL, the volume losses were 0.06 and 0.17 mm(3), and the mean maximum depths were 35.1 and 48.7 microm for the bur and disk groups, respectively. There were no significant differences in enamel loss between the 2 groups of teeth without WSL (P =.12). However, in teeth with WSL, the burs removed less enamel than the disks (P = 0.006). Scanning electron microscope examination showed that any damage on the enamel surface was usually located in the cervical third of the teeth. On most specimens, even though tooth surfaces appeared resin-free to the naked eye, there were remnants of it. The differences between groups were so small that they might be clinically insignificant.     

Effects of polishing techniques on the surface roughness of acrylic denture base resins

STATEMENT OF PROBLEM: Rough surfaces of denture bases promote adhesion of microorganisms and plaque formation. It is therefore important to know how different polishing systems affect surface roughness of denture base acrylic resins. PURPOSE: The objective of this study was to compare the effects of 4 chairside polishing kits and 2 conventional laboratory techniques used for polishing 3 different acrylic denture base resins. MATERIAL AND METHODS: Using contact profilometric measurement, the surface texture of 54 specimens (15x30x3 mm) per acrylic material (autopolymerized ProBase Cold, heat-polymerized ProBase Hot, and injection heat-polymerized SR Ivocap plus) was studied before and after cutting with a tungsten carbide bur, and during and after chairside polishing with 4 polishing kits (Exa Technique, Acrylic Polisher HP blue, AcryPoint, Becht Polishing Cream), and after conventional polishing with 2 polishing systems (Universal Polishing Paste for Resins and Metals, Lesk Polishing Liquid). There were 9 specimens for each acrylic resin material and polishing method combination. Conventional lathe polishing with polishing paste served as the control. Mean average surface roughness (Ra) values of each specimen group were analyzed using a 2-way analysis of variance, the Scheffé post-hoc test, and paired t test (alpha=.05) with the Bonferroni adjustment. After testing the polished acrylic resin surfaces were evaluated under a scanning electron microscope. RESULTS: The highest mean average surface roughness (Ra=2.86+/-0.8 microm to 3.99+/-1.31 microm) was measured for surfaces finished with a tungsten carbide bur. The lowest surface roughness values (Ra=0.02+/-0.01 microm) were determined for acrylic resin specimens polished with a lathe and polishing paste. The Ra values of resin specimens after polishing with chairside silicone polishing kits ranged from 0.05+/-0.0 microm to 0.35+/-0.05 microm. Mean average Ra values of specimens polished with a polishing cream alone (Ra=1.01+/-0.17 microm to 1.68+/-0.47 microm) were significantly higher (P<.05) than those obtained with other polishing systems tested, which was confirmed by scanning electron microscope images of acrylic resin surfaces. Significant differences in mean average surface roughness were found between autopolymerizing and injected heat-polymerizing resin specimens. In addition, scanning electron microscopy revealed increased porosity of autopolymerizing resin specimens. CONCLUSIONS: Conventional laboratory polishing was found to produce the smoothest surface of denture base acrylic resin. Chairside silicone polishing kits produced a significantly smoother surface of acrylic resin than specimens polished with a tungsten carbide bur. The presence of large pores was characteristic for the autopolymerizing resin material.     

Evaluation of the Surface Roughness in Dental Ceramics Submitted to Different Finishing and Polishing Methods

Ceramic restorations have been widely used in dentistry. These restorations often require intraoral adjustment with diamond burs after their cementation causing increasing roughness of the ceramic surface. Consequently some finishing and polishing methods have been used to minimize this occurrence. The aim of this study is to evaluate the roughness of the ceramic surfaces submitted to different finishing and polishing methods. 144 specimens of VITAVM^®7, VM^®9 and VM^®13 (VITA Zahnfabrik) ceramics were fabricated and submitted to grinding using diamond burs. They were then divided into 15 groups (five of each ceramic type). Groups 1, 6 and 11—positive control (Glaze); Groups 2, 7 and 12—negative control (no polishing); Groups 3, 8 and 13—polished with abrasive rubbers (Edenta), felt disc and diamond polishing past; Groups 4, 9 and 14—polished with abrasive rubbers (Shofu), felt disc and diamond polishing past; Groups 5, 10 and 15—polished with aluminum oxide discs (Sof-Lex, 3M-ESPE), felt disc and diamond polishing paste. The roughness of the samples surfaces were measured using the rugosimeter Surfcorder SE 1700 and the data were submitted to statistical analysis using ANOVA and Tukey test at a level of significance of 5 %. There was statistically significance difference between the positive control groups and the other groups in all the ceramic types. Mechanical finishing and polishing methods were not able to provide a surface as smooth as the glazed surface for the tested ceramics. To assist dental practitioners to select the best finishing and polishing methods for the final adjustment of the ceramic restorations.     

Surface roughness of new microhybrid resin-based composites

BACKGROUND: Rough, poorly polished resin-based composite (RBC) surfaces contribute to staining, plaque accumulation, gingival irritation and recurrent caries. Proper finishing and polishing enhance both the esthetics and the longevity of restored teeth. METHODS: The authors evaluated the influence of various finishing and polishing techniques on the surface roughness of four microhybrid RBCs. Thirty samples of each material were cured under Mylar matrix strips (Yates and Bird/Motloid, Chicago). All microhybrid RBC specimens were finished with multifluted carbide burs, except for the Mylar matrix strip samples, and then were polished using one of four finishing systems: Sof-Lex contouring and polishing disks (3M ESPE, St. Paul, Minn.); Enhance Finishing System (Dentsply-Caulk, Milford, Del.) followed by Prisma Gloss (Dentsply-Caulk) polishing paste application; Astropol finishing, polishing and high-gloss polishing system (Ivoclar Vivadent, Schaan, Liechtenstein); and Astrobrush polishing system (Ivoclar Vivadent). The authors tested the samples to obtain average surface roughness and analyzed the values. RESULTS: The use of the Astrobrush technique caused the greatest roughness on all RBC specimens. The smoothest surface was produced with a carbide bur followed by aluminum oxide disks, Astropol technique and Enhance technique. Overall, there were differences in surface quality among the materials. InTen-S (Ivoclar Vivadent) had statistically lower surface roughness values after finishing and polishing with the Astrobrush technique, compared with the other RBCs. CONCLUSION: The highest surface roughness values were achieved after the Astrobrush technique was used. The Sof-Lex aluminum oxide disks, and Enhance and Astropol techniques provided the smoothest surface. CLINICAL IMPLICATIONS: The Sof-Lex, Enhance and Astropol techniques produced a smooth surface after the finishing and polishing of materials, while the Astrobrush technique yielded the least favorable results.     

Effect of finishing technique on the microleakage and surface texture of resin-modified glass ionomer restorative materials

PURPOSE: The purpose of this study was to evaluate the effects of wet and dry finishing/polishing procedures on the microleakage and surface texture of resin-modified glass ionomer (RMGI) restorative materials. MATERIALS AND METHODS: Class V cavity preparations were made at the cemento-enamel junction (CEJ) on the buccal and lingual surface of 30 extracted human molars. The teeth were restored in three groups of 10 (20 preparations in each group) using Fuji II LC and Vitremer, both RMGIs, and Fuji II, a capsulated conventional glass ionomer cement (control). One restoration per tooth was finished/polished with copious applications of water and the other was finished/polished without water. All restorations were finished/polished using a sequence of four abrasive disks. Finishing/polishing was initiated according to manufacturers' instructions-immediately after light-curing Fuji II LC and Vitremer, and 15min after placement for Fuji II. The specimens were thermocycled and subjected to a silver nitrate leakage test. Each tooth was sectioned buccolingually and examined with an optical microscope at 40x to determine the extent of microleakage at enamel and dentin margins. The data were subjected to a non-parametric statistical analysis. To evaluate surface roughness after polishing, three disks each of Vitremer and Fuji II LC were fabricated in Teflon molds. One disk of each material was not finished/polished (control). The others were finished/polished using Sof-Lex abrasive disks. One specimen of each material was kept wet during all finishing/polishing procedures, while the other was kept dry. Atomic force microscopy was used to determine the average roughness (R(a)) of the specimens. RESULTS: For each material, microleakage at the enamel margin was very slight. Leakage of the conventional glass ionomer Fuji II was severe at dentin margins. Statistical analysis indicated that both Vitremer and Fuji II LC had significantly less leakage than Fuji II, and that Vitremer had significantly less leakage than Fuji II LC (p<0.05). Leakage at enamel margins was significantly less than at dentin margins. Differences related to wet and dry polishing were not statistically significant. Profilometry data indicated that polished specimens were rougher than those cured against a Mylar strip. Wet polishing created greater surface roughness than dry polishing. CONCLUSIONS: RMGIs rather than conventional glass ionomers should be used in Class V cavity sites to allow immediate finishing and to reduce the incidence of microleakage. Dry finishing of RMGIs with abrasive disks is recommended because it produces a smoother surface and does not contribute to microleakage. However, wet finishing of conventional glass ionomers is still recommended to avoid desiccation.     

Enamel surface roughness following debonding using two resin grinding methods

The purpose of this study was to assess quantitatively the roughness of the enamel surface following debonding using two resin removal methods. The enamel surface of 30 premolar crowns was covered with black tape with a 3 mm window on the middle buccal third to standardize the area of analysis. The initial enamel surfaces were subjected to profilometry, registering four roughness parameters (Ra, Rq, Rt and Rz). The brackets were bonded to the plaster-embedded enamel surfaces with a chemically cured, no-mix adhesive, and debonded after 1 week. Resin removal in half of the specimens was performed with an eight-bladed carbide bur, and in the other half with an ultra-fine diamond bur, both attached to a high speed hand piece; a second profilometric measurement was made after resin removal. Finishing of all surfaces was achieved with Soflex discs and a third registration of roughness followed. The duration of each resin removal protocol was also recorded. The results were analysed with two-way ANOVA and the Newman-Keuls test with the two resin grinding modes and the three intervals serving as discriminating variables (n = 15). For the duration results, a one-way ANOVA was used. Significant differences (P < 0.05) were observed with respect to enamel roughness parameters between the two resin grinding methods used, while there was no consistent roughness-reducing effect of finishing with Soflex discs. Resin removal with a diamond bur was achieved in approximately half the time compared with the eight-bladed bur. The increase in most roughness variables induced by the debonding procedures was not reversed at the end of the finishing stage, regardless of the resin removal protocol used, suggesting an irreversible effect on enamel texture.     

Effect of finishing and polishing procedures on surface roughness, gloss and color of resin-based composites

PURPOSE: To evaluate the effects of different finishing and polishing procedures on surface roughness, gloss and color of five resin composites: two experimental microhybrid composites - FZ-Dentin (FZD) and FZ-Enamel (FZE), one commercial microhybrid composite - Esthet-X (EX), and two microfilled composites - Heliomolar (HM) and Renamel Microfill (RM). METHODS: Surface roughness, gloss and color of the disc-shaped specimens (10 mm in diameter and 2-mm thick) were measured as Mylar (baseline), 16-fluted carbide bur and polishing were completed. Sixteen specimens of each composite were randomized to four groups of four. After finishing with a 16-fluted finishing bur, each group was polished by a different system: 1. Astropol (A), 2. Sof-lex disc (S), 3. Po-Go (P), 4. Enhance (E). Average surface roughness (Ra) was measured with a profilometer. Gloss measurements were performed using small-area glossmeter, while color coordinate values were recorded using a spectrophotometer. A deltaE*ab< or =1 was considered to be the limit of perceptibility. RESULTS: The order of surface roughness ranked according to polishing system (for all five composites together) was: P < S < E < A. The order of surface roughness ranked according to composites was: RM < FZD < FZ < HM < EX. The order of gloss ranked according to polishing system (for all five composites together) was: P > E > A > S. The order of gloss values for the polished composites (for each of four polishing systems) was: RM > FZD > FZE > HM > EX. Fisher's PLSD intervals at the 0.05 level of significance for comparisons of means of surface roughness among five composites and four polishing systems were 0.01 and 0.01 microm, respectively. Fisher's PLSD intervals at the 0.05 level of significance for comparisons of means of gloss among five composites and four polishing systems were 6 and 5 GU, respectively. Color differences (deltaE*ab) among five composites and four polishing methods were found to range from 0.2 to 1.1.     

Surface geometry of three packable and one hybrid composite after finishing

This study compared the effects of different finishing techniques on the surface of a traditional hybrid composite and three packable composites. Four composites were used in the study (Herculite XRV/Kerr, Definite/Degussa, SureFil/Dentsply and Solitaire/Heraeus-Kulzer). Fifty specimens were made of each material, sized 7 x 7 x 4 mm. Fifteen specimens of each material were subjected to the following finishing procedures: (1) a 30 microm diamond, (2) a 30 microm and a 20 microm diamond and (3) a 30 pm diamond followed by a tungsten carbide finishing bur. As a reference, five specimens of each material were treated by Sof-Lex discs (3M). For quantitative surface evaluation, laser-stylus profilometry was used. Roughness parameters included average roughness (Ra) and profile-length-ratio (LR). Statistical analysis was performed with one- and two-way Anova and Scheffé post-hoc tests. Qualitative surface evaluation in SEM was performed at a tension of 25kV. Significant effects were found with both the composites and the finishing methods with respect to surface roughness (p < 0.001 for Ra and LR). A 30 microm diamond caused the greatest roughness on all composites, with Ra ranging from 2.015-2.079 microm (p<0.001). After finishing using methods 2 and 3, the Solitaire surfaces were significantly smoother (p < 0.001 for LR). The lowest roughness values were achieved after using disks; again, the Solitaire specimens yielded the lowest Ra and LR values (p < 0.001 except for Sure-Fil). With scanning electron microscopy, surface areas with signs of destruction were found after using a 30 microm diamond on Definite specimens.