Effect Of Different Polishing Techniques Research Articles

Effect of different polishing techniques on surface properties and bacterial adhesion on resin-ceramic CAD/CAM materials.

The aim of this study is to evaluate the adhesion of Streptococcus mutans on the surface of CAD/CAM materials with various surface treatments. Vita Enamic, Lava Ultimate, and Cerasmart materials were used in this study. A total of 90 samples were prepared (n = 10). After various finishing and polishing procedures (non-polished, manual polished, and glazed), surface roughness (SR) measurements, surface free energy (SFE), and elemental and topographic analysis with FIB-SEM/EDX were used to evaluate the samples' surface properties. To improve bacterial adhesion, CAD/CAM materials were covered with sterile artificial saliva containing mucin for pellicle formation and incubated for 1h at 37°C. Bacteria were then inoculated into the pellicle-coated specimens, and incubation was performed at 37°C for 24h. Bacterial adhesion was determined as × 105CFU/mL and monitored using FIB-SEM analysis. The Kolmogorov-Smirnov test was used to statistically analyze the normality of the distribution; the groups were then compared using one-way ANOVA and Tukey's test. The SR of the control group was statistically higher in all materials (p < 0.05). There were no statistically significant differences in SR between all materials in the non-polished and manual polished groups (p > 0.05). The Vita Enamic control group exhibited the highest SFE value. The highest S. mutans adhesion was observed in non-polished (p < 0.05). Vita Enamic samples had higher CFU than other groups. Non-polished surfaces showed higher SR and bacterial adhesion. Polishing processes affected the surface properties and bacterial adhesion. Care must be taken in polishing restorations to minimize the risk of bacterial adhesion and recurrent caries. In this study, the materials used for dental treatments are in vitro evaluated. Due to that, this study is not registered to clinical trials.

Surface Characterization of Monolithic Zirconia Following Treatment with Different Polishing Techniques

The purpose of this study was to evaluate the effects of different polishing techniques on the topographical features and phase transformation of monolithic zirconia. Four brands of zirconia were ground and polished using one of four systems. All zirconia specimens were ground with a fine-grit diamond bur (GB) prior to polishing procedures. The surface roughness and phase transition (XRD) were evaluated, and surface characterizations (SEM and XPS) were performed. The highest roughness was obtained with the Tob system. The strongest diffraction peak in the obtained XRD patterns was at 2θ=30.246°. No monoclinic phase change was found in any group. The XPS analysis showed that the atomic percentages of yttrium in the specimens of Cercon before and after polishing were the highest of any sample. All the polishing systems tested may not adversely affect the phase transformation of monolithic zirconia. The Tob system resulted in the highest roughness. The XPS analysis showed that grinding and polishing had some effects on the properties of zirconia from a microscopic point of view.

Effect of different polishing techniques on surface roughness and bacterial adhesion of three glass ionomer-based restorative materials: In vitro study.

BackgroundAlthough many reports concluded that polishing of glass ionomers is crucial for smoother surface and limiting the adhesion of cariogenic bacteria, there is no specific surface treatment protocol recommended. A novel material in the same category was released recently claimed to have surface smoothness comparable to resin composite and bacterial adhesion less than other types of glass ionomers. In this study, different polishing systems were tested with three glass ionomers one of them is the novel material to find the most appropriate polishing protocol. Objectives: To evaluate and compare the surface roughness and bacterial adhesion to resin modified glass ionomer, bioactive ionic resin and conventional glass ionomer restorative materials after different polishing protocols in vitro. Material and MethodsThe materials tested includes resin modified glass ionomer, bioactive ionic resin, and conventional glass ionomer. The polishing protocols were divided into four groups: group 1 = (Mylar matrix strips, Control), group 2 = (one-step, PoGo), group 3 = (two-step, Prisma Gloss) and group 4 = (three-step, Sof-Lex). From each material, eleven cylindrical specimens were prepared for each group according to the manufacturers’ instructions. The surface roughness for all specimens was measured using atomic force microscope in tapping mode. the same specimens were subjected to bacterial adhesion testing after being coated with artificial saliva. Data were analyzed with two-way analysis of variance followed by Post hoc multiple comparisons. ResultsThe highest Ra and S. mutans adhesion values were recorded for all materials in two-step group. The lowest Ra and S. mutans adhesion values were seen in one-step and three step groups. ConclusionsOne-step polishing system was more effective and may be preferable for polishing of the three studied glass ionomer-based materials compared to two-step and three-step systems. Key words:Activa bioactive restorative, glass ionomer, surface roughness, bacterial adhesion, surface treatment.

Effect of different polishing techniques for composite resin materials on surface properties and bacterial biofilm formation

ObjectivesBoth direct and indirect techniques are used for composite resin material (CRM) restorations. Polishing processes are needed in both techniques after intraoral adjustment. However, it is unclear as to which polishing technique should be preferred with respect to decreasing biofilm. The purpose of thisin vitro study was to evaluate the surface properties and Streptococcus mutans biofilm formation on direct and indirect CRMs after using different polishing techniques. MethodsTwo CRMs (direct and indirect) and four polishing techniques (aluminium oxide discs, diamond polishing paste, aluminium oxide polishing paste, and silicon carbide brush) were evaluated. The specimens were prepared for taking scanning electron microscopy images (n = 2) and determining surface roughness, surface free energy, and bacterial biofilm formation (BBF) with colony-forming unit counting and confocal laser scanning microscopy assays (n = 7). The data were analysed using two-way analysis of variance with Bonferroni as a post hoc test and Pearson’s correlation (p < .05). ResultsThe surface roughness values in the control group were higher than those in the diamond polishing paste group (p = 0.025), but the values in the aluminium oxide polishing paste and silicon carbide brush groups were comparable with those in the control group (p = 0.156 and p = 1.000, respectively). The highest surface free energy values were recorded in the silicon carbide brush group (p < 0.001), whereas there were no differences found among the other groups (p > 0.05). The highest BBF was seen in the silicon carbide brush (p < 0.001) and direct CRM (p < 0.001) groups. ConclusionBBF on the surface of direct CRMs differed from that on indirect CRMs after polishing the surface. The tested polishing techniques significantly influenced surface properties and BBF. Clinical significanceIn situations that require the intraoral adjustment of CRMs, polishing with a diamond polishing paste seems to be a good option to polish the surface of both direct and indirect CRMs because the diamond polishing paste results better in terms of decreasing biofilm formation and improving surface properties.

EFFECT OF TWO POLISHING TECHNIQUES ON SURFACE ROUGHNESS OF THREE DIFFERENT DENTURE BASE MATERIALS (AN IN VITRO STUDY)

INTRODUCTION: A direct link was found between surface roughness, the accumulation of plaque and the adherence of microorganisms concerning acrylic resins. However, the surface properties of the new thermoplastic materials remain questionable especially after using the conventional finishing and polishing techniques. Studying surface properties of each material makes the recommendation of the proper techniques easier. OBJECTIVES: This in vitro study intended to compare three types of denture base materials in regarding to the effect of different polishing techniques on their surface roughness. MATERIALS AND METHODS: 36 specimens were incorporated in this study. 12 specimens were in each group. 3 groups were formed: Group A: Heat cured Polymethylmethacrylate (PMMA). Group B: Thermoplastic Polyamides. Group C: Thermoplastic Acetal. Dimensions of specimens were (20×20×3 mm) with projection at the side. Statistical analysis was carried out using two way analysis of variance (ANOVA). Statistical significance was defined at P≤0.05. RESULTS: Technique no. 1 showed a high significant value in compared to technique no.2 for polishing the tested materials. CONCLUSIONS: PMMA was the highest affected group followed by thermoplastic acetal and the last affected group was thermoplastic polyamide. Prepolishing rubberizing with rubber bur improves the polishing procedure. RESULTS: Remarkable improvement in the histology and the ultrastructure of the alveolar bone of rats in Group III was observed. Moreover, hematological values revealed significant decrease in the inflammatory condition of rats with induced RA after fish oil treatment. CONCLUSIONS: Rheumatoid arthritis is an important risk factor for alveolar bone loss. The treatment of the RA induced rats with fish oil not only prevented the alveolar bone resorption and stimulated new bone formation, but also reduced relatively the level of rheumatoid factor in the blood.

The effects of different polishing techniques on the staining resistance of CAD/CAM resin-ceramics.

PURPOSEThe purposes of this study were to evaluate the staining resistance of CAD/CAM resin-ceramics polished with different techniques and to determine the effectiveness of the polishing techniques on resin-ceramics, comparing it with that of a glazed glass-ceramic.MATERIALS AND METHODSFour different CAD/CAM ceramics (feldspathic ceramic: C-CEREC Blocs, (SIRONA) and three resin-ceramics: L-Lava Ultimate, (3M ESPE), E-Enamic, (VITA) and CS-CeraSmart, (GC)) and one light cure composite resin: ME-Clearfil Majesty Esthetic (Kuraray) were used. Only C samples were glazed (gl). Other restorations were divided into four groups according to the polishing technique: nonpolished control group (c), a group polished with light cure liquid polish (Biscover LV BISCO) (bb), a group polished with ceramic polishing kit (Diapol, EVE) (cd), and a group polished with composite polishing kit (Clearfil Twist Dia, Kuraray) (kc). Glazed C samples and the polished samples were further divided into four subgroups and immersed into different solutions: distilled water, tea, coffee, and fermented black carrot juice. Eight samples (8 × 8 × 1 mm) were prepared for each subgroup. According to CIELab system, four color measurements were made: before immersion, immersion after 1 day, after 1 week, and after 1 month. Data were analyzed with repeated measures of ANOVA (α=.05).RESULTSThe highest staining resistance was found in gl samples. There was no difference among gl, kc and cd (P>.05). Staining resistance of gl was significantly higher than that of bb (P<.05). Staining resistances of E and CS were significantly higher than those of L and ME (P<.05).CONCLUSIONCeramic and composite polishing kits can be used for resin ceramics as a counterpart of glazing procedure used for full ceramic materials. Liquid polish has limited indications for resin ceramics.

In vitro evaluation of the effect of different polishing techniques on the surface roughness of composite resins submitted to at-home and in-office bleaching procedures.

Objective:Bleaching agents may affect the properties of dental materials. The aim of this study was to evaluate the effect of different polishing techniques on the surface roughness of composite resins submitted to the at-home and in-office bleaching treatment.Materials and Methods:Disc-shaped specimens were carried out of nanofilled and microhybrid composites (n = 10). Finishing step was performed after light curing (L1) and polishing after 24 h with two systems (L2). Then, specimens were submitted to the home or in-office bleaching procedures, and roughness was re-evaluated (L3). The surface roughness (Ra) readings were measured at L1, L2, and L3 times using a profilometer. Data were statistically analyzed by multiple-way analysis of variance and Tukey test (α = 0.05).Results:The polishing procedures decreased Ra for both composites compared to baseline values (L1). The roughness of specimens polished with jiffy did not present significant difference after polishing step (L2) and bleaching treatment (L3). However, the groups polished with Sof-Lex discs had increase on the Ra values after bleaching.Conclusion:The polishing is an important procedure to reduce the roughness of dental restorations and composite surface polished with jiffy system improved the degradation resistance to the bleaching agents compared to Sof-Lex discs.

Investigation of the effect of different polishing techniques on the surface roughness of denture base and repair materials

The rough surface of denture base materials may cause plaque accumulation and staining. Thus,theeffectiveness of polishing techniques should be known. The purpose of this study was to compare the effects of chairside polishing kits and conventional laboratory techniques on the surface roughness of denture base and repair materials. Ninety-six specimens, 50 ±1 mm in diameter and 0.5 ±0.05 thick, were fabricated from heat-polymerized acrylic resin (HP), polyamide resin (PR), and autopolymerizing resin (AP) and submitted to grinding with a tungsten carbide bur. The specimens were divided into 4 groups according to the polishing technique used: control group without polishing, conventional laboratory polishing, polished with Acrylic Polisher HP blue kit, and polished with AcryPoint polishing kit. Surface roughness (Ra) was measured after polishing with a profilometer. Data were analyzed with a 2-way analysis of variance, and the Tukey honestly significant difference (HSD) test was performed to identify significant differences (α=.05). The polishing techniques significantly affected the Ra of denture base materials (P<.001). The highest mean averageRa was measured for the control group. The lowest Ra values were determined in specimens exposed to conventional laboratory polishing techniques. No significant differences were found between Acrylic Polisher HP blue and AcryPoint polishing kits (P>.05). Statistically significant differences were found in the Ra between the PR and both the HP and AP (P<.001); PR exhibited the highest Ra values. Conventional laboratory polishing was the most effective polishing technique. A significantly smoother surfacethan that of the specimens in the control group was produced with chairside silicone polishing kits.

Losses of essential mineral nutrients by polishing of rice differ among genotypes due to contrasting grain hardness and mineral distribution

The effect of different polishing techniques on loss of mineral elements from rice grains was quantified using a panel of indica and tropical japonica genotypes, previously classified as differing in ease of polishing. Gradients in mineral elements across the bran-endosperm interface were quantified using micro-scaled precision abrasive polishing in combination with inductively coupled plasma mass spectrometry and synchrotron X-ray fluorescence microscopy. Frictional polishing, similar to that of commercial mills, i.e. 8–10% loss of grain weight, reduced the concentration of Fe, Mg, P, K and Mn by 60–80% in all genotypes. Following gentler polishing (3–5% weight loss), genotypes classified as difficult to polish showed smaller decreases in Fe, Mg, P, K and Mn compared to genotypes classified as easy to polish. The concentration of other elements, e.g. Zn, S, Ca, Cu, Mo and Cd, showed comparable reductions (<30%) irrespective of polishing technique or ease of polishing. The different patterns of polishing losses of minerals reflected their distribution within the grain. Five-fold differences in the reduction of Zn concentration during polishing were observed for different genotypes which started with similar Zn concentrations in the unpolished grain, thus showing clear potential for selecting genotypes with reduced polishing losses of Zn.

Effects of different surface treatments on the color stability of various dental porcelains

Background/purpose There is a lack of information in the few studies reporting on the stainability of dental porcelain materials. However no studies have been found that investigated effects of polishing methods and staining agents on the color stability of dental porcelains. The purpose of this study was to evaluate the effects of different polishing techniques on the color stability of various dental porcelains. Materials and methods Fifty-five specimens were prepared for each of feldspathic (Vita VMK 95, Ceramco III), low-fusing porcelain (Matchmaker), and machinable feldspathic porcelain blocks (Vitablocs Mark II). The prepared specimens were divided into 11 groups ( n = 5) representing different polishing techniques including a control (no surface treatment), glaze, and nine other groups which were finished and polished with a polishing disc (Sof-Lex), two porcelain polishing kits (NTI, Dialite II), a diamond polishing paste (Sparkle), a zirconium silicate-based cleaning and polishing prophy paste (Zircate), an aluminum oxide polishing paste (Prisma Gloss), and combinations of these. Specimens were stored for 48 hours at 37°C in a coffee solution. The color of all specimens was measured with a colorimeter before and after exposure, and color changes (ΔE) were calculated. Data were analyzed with a two-way analysis of variance, and mean values were compared by the Tukey’s honest significant difference test (α = 0.05). Results When comparing the four different porcelain materials, Ceramco III demonstrated the highest ΔE value. No significant difference was observed among the porcelain material groups of Mark II, Matchmaker MC, and VMK 95 (P = 0.074). When comparing the polishing techniques, the lowest ΔE values were observed in Group Gl for all porcelain materials tested. No significant difference was observed among Groups Sl, Di, and Pk, (P = 0.883), and these Groups demonstrated significantly higher ΔE values than Group Gl (P < 0.05). Conclusions Within the limitations of this study, the results suggest that feldspathic and low-fusing porcelain specimens were found to be more color-stable for glazed specimens versus polished specimens regardless of whether they were stained with the coffee solution. Glazed and polished specimens with different polishing materials demonstrated that the ΔE values were at an acceptable level for all of the porcelain materials tested (1 < ΔE < 3.7).

Effects of different polishing techniques on the surface roughness of dental porcelains

ObjectiveThe purpose of this study was to evaluate the effects of different polishing techniques on the surface roughness of dental porcelains.Material and MethodsFifty-five cylindirical specimens (15x2 mm) were prepared for each feldspathic (Vita VMK 95, Ceramco III) and low-fusing dental porcelain (Matchmaker). Fifty-five specimens of machinable feldspathic porcelain blocks (Vitablocs Mark II), (12x14x18 mm) were cut into 2-mm-thick slices (12x14 mm) with low speed saw. The prepared specimens were divided into 11 groups (n=5) representing different polishing techniques including control ((C) no surface treatment), glaze (G) and other 9 groups that were finished and polished with polishing discs (Sof-Lex) (Sl), two porcelain polishing kits (NTI (Pk), Dialite II (Di)), a diamond polishing paste (Sparkle) (Sp), a zirconium silicate based cleaning and polishing prophy paste (Zircate) (Zr), an aluminum oxide polishing paste (Prisma Gloss) (Pg), and combinations of them. The surface roughness of all groups was measured with a profilometer. The data were analyzed with a 2-way analysis of variance, and the mean values were compared by the Tukey Honestly Significant Difference test (α=0.05).ResultsFor all porcelain material groups, the lowest Ra values were observed in Group Gl, Group Sl, Group Pk, and Group Di, which were not significantly different from each other (p>0.05).When comparing the 4 different porcelain materials, the machinable feldspathic porcelain block group (Mark II) demonstrated statistically significantly less Ra values than the other porcelain materials tested (p<0.05). No significant difference was observed between the VMK 95 and Ceramco III porcelain groups (p=0.919), also these groups demonstrated the highest Ra values.ConclusionSubjected to surface roughness, the surfaces obtained with polishing and/or cleaning-prophy paste materials used alone were rougher compared to the surfaces finished using Sof-lex, Dialite, and NTI polishing kit. Polishing kits and discs were found more effective than the polishing pastes used alone or combined use with Sof-lex discs, thus improving surface smoothness.

Effects of different food colorants and polishing techniques on color stability of provisional prosthetic materials

The main objective was to investigate the effects of different polishing techniques on the color stability of provisional prosthetic materials upon exposure to different staining agents by mimicking the oral environment in vitro. Fifty-six cylindrical specimens were prepared for each type of material: bis-acryl and light-polymerized composite resins, and methyl methacrylate- and ethyl methacrylatebased resins. The specimens were polished using seven different polishing techniques and then immersed in four different staining agents. Color was measured with a spectrophotometer before and after immersion, and color changes (DeltaE) were calculated. The effects of the type of provisional material, polishing procedure, staining agent, and their interactions on color stability were significant (p<0.05). Amongst these factors, the staining agent exerted the strongest effect on color stability. Amongst the provisional materials tested, methacrylate-based resins exhibited the highest color stability irrespective of polishing technique and staining agent.