Mylar Strip Research Articles

The Effect of Various Polishing Systems on the Surface Roughness of Two Resin Composites—An In Vitro Study

The long-term success of a composite restoration largely depends on its smoothness, which can be achieved by the appropriate polishing tools and material selection. The purpose of this study was to evaluate the surface roughness of two composite materials after the application of selected polishing systems. Filtek Ultimate (FU) and Filtek Z250 (FZ) were tested. Forty specimens of each material were prepared. After polymerization under a Mylar strip, the surface roughness of five samples from each group was measured. Subsequently, all specimens were ground by 600 grit sandpaper. The surface roughness of five samples per group was tested again. The samples from each group were randomly assigned to eight subgroups, and polished by Sof-Lex, Sof-Lex Diamond Polishing System, Super Snap, One Gloss, Astrobrush, Stainbuster, Enamel Shiny, and Jiffy Polishing System. The collected data were analyzed using the Shapiro–Wilk and Kruskal–Wallis tests. The lowest Ra coefficient after polishing is found in the Super Snap groups (FU—0.077 μm, FZ—0.085 μm). The lowest Rlr coefficient is measured in the Enamel Shiny group for FU (1.000), and for Sof-Lex, Sof-Lex Diamond Polishing System, and Jiffy Polishing Kit for FZ (1.001), and only slightly higher for Super Snap (FU—1.001, FZ—1.002). The roughest-measured surface is in the One Gloss group for FU (Ra—0.657 µm, Rlr—1.009), and Astrobrush group for FZ (Ra—0.525 μm, Rlr—0.011). Additionally, it was not confirmed that the nanoparticle material (FU) demonstrates better results than the microhybrid one (FZ). Different polishing systems produce varying surface roughness. The most effective polishing system is Super Snap. The structure of composites does not significantly affect their surface roughness after polishing.

Effect of Different Repolishing Procedures on The Color Change of Alkasite

Objectives: An esthetic restoration with an unacceptable color is the main cause for replacement of anterior tooth restorations. The aim of this study is to evaluate the effect of repolishing on the color change of the new material group of alkasite after exposure to coffee solution. Materials and Methods: Alkasite material placed in Teflon molds with a diameter of 8 mm and a height of 2 mm was polymerized under the application of mylar strip and a total of 32 samples were obtained. The samples were randomly immersion into groups. Group R: Diamond grained polishing rubbers, Group D: Aluminum oxide discs are applied and the polishing process is completed. After the first color measurement was made, it was immersed in coffee and the measurement was repeated 1 week later. L was divided into two groups (n=8) and repolished with rubber (RR) and discs (RD). In the D group, re-polishing was done with rubber (DR) and disc (DD) and color measurements were repeated. Results were analyzed by using one-way ANOVA and Tukey test at 95% confidence interval. Results: The greatest color change (ΔE00) was in group R. At the end of seven days, similar color change values were found between the groups of R and D (p > 0.05). There is no difference between the RR and RD groups. Significantly less color change was observed in the DD group than in the RR and RD groups (p = .003, p = .042, respectively). Similarly, the DR group showed less color change than the RR group (p = .015). Conclusions: The color stability of the alkasite was affected by the polishing procedure. The repolishing process reduced the color change, but not at a clinically acceptable level.

OFİS TİPİ BEYAZLATMANIN FARKLI KOMPOZİT REZİNLERİN YÜZEY PÜRÜZLÜLÜĞÜ ÜZERİNE ETKİSİ

Objective: The aim of this study is to investigate the effect of a high concentration hydrogen peroxide bleaching agent on the surface roughness of four different composite resins. Material and Methods: For this purpose, with the help of teflon molds, a total of 24 composite samples (10 x 2 mm) were prepared, with n = 6 for each composite group. The samples were placed in teflon molds in two layers of 2mm and covered by transparent mylar strips at the top and bottom surfaces. The material was compressed with finger pressure between 1mm thick glass plates. The tip of the light device was applied directly from the transparent tape surface for the polymerization of the samples. Polymerization of the samples was carried out using LED light device in each layer. After the samples were polished with finishing discs, they were kept at 37 ° C for 24 hours in the distilled water. Surface roughness values (Ra) of all samples were measured with a profilometer device. After the first measurements, a whitening agent containing 35% hydrogen peroxide was applied to the surfaces, and surface roughness measurements were repeated after this process. Data were analyzed statistically using analysis of variance (ANOVA) and Tukey tests. Results: Profilometric evaluations showed a small increase in the surface roughness of all samples with a bleaching agent. When the initial and treated measurements of the groups were compared, the difference between the measurements was found statistically insignificant. (P> 0.05) Conclusion: The office bleaching agent containing 35% hydrogen peroxide did not make any difference in the roughness of the nanohybrid and microhybrid composite resins.

Efficacy comparison of various oxygen lnhibition layer (OIL) minimizing agents on composite resin by analysis of two different physical properties

Introduction: Composite resins are the most common restorative materials that are used these days and have been radically improving over the past few years. Their polymerisation reaction can be inhibited during light-curing due to the oxygen presence in atmosphere. Aim/objective: The aim of this study is to evaluate effect of different air inhibition coating strategies on composite resin material in terms of hardness and discolouration. Material and Methodology: Composite discs of 6.5 X 2mm were prepared for samples which were cured under a) 0.5mm thick mylar strip b) thin layer of glycerine c) layer of KY jelly (commercial lubricant) d) air cure. These samples were dipped in cola, turmeric milk, coffee and distilled water for 14 days. Spectrophotometric analysis was done to assess the colour change and Vicker’s hardness test for assessment of the hardness. Statistical analysis was done and the results were concluded. Results: The results were analyzed with ANOVA one-way test followed by Student Newman-Keul test. Moreover, multiple comparisons of means were performed using the Student t-test (p<0.05). Conclusion: Presence of Oxygen inhibition layer(OIL) on surface layer of composite affected the specimens adversely by reducing the microhardness and increasing instability of colour.

Effect of immediate and delayed finishing and polishing procedure on Streptococcal mutans adhesion and micro-hardness of composite resin surface: An in-vitro study

Proper finishing and polishing have become the indispensable step in clinical restorative dentistry due to increased aesthetic demands. There are several polishing systems containing fine particle size abrasives. The adhesion of bacterial plaque to restoration depends on the surface properties and composition of materials. In literature, surface roughness after polishing is well documented, but the timing, i.e., immediate or delayed polishing affecting the bacterial adherence and microhardness on the composite needs research. As the Streptococcus mutans has a major role in primary and secondary caries, so in this light, this study is conducted to investigate the best timing of polishing affecting the bacterial adhesion and microhardness of composite resin.: To evaluate the Streptococcal mutans adhesion and microhardness of composite resin after polishing them, immediately and after 24 hours of curing.: Sixty specimens were made from composite resin Filtek Z 350 XT (3M ESPE) of 6mm diameter and 4mm height, was cured by placing a Mylar strip and divided into 3 groups- Group 1 the control group with only MYLAR-STRIP, Group 2- Polishing system SOF-LEX (3M ESPE Dental products St. Paul, MN,USA.) Group 3- Polishing with SUPER-SNAP (Shofu Inc., Kyoto, Japan). Group 2 and 3 were further divided into two subgroups according to the polishing time- immediate and delayed. The Streptococcal mutans adhesion for each group was measured by colony forming units and compared. The mean log of CFU/mL present in the biofilm was also calculated. The results of bacterial adherence was analysed by three-way ANOVA (analysis of variance) (p<0.01) and the ANOVA two-way of variance was used for checking microhardness (p<0.01). A p value <0.01 was considered to indicate a statistically significant for both bacterial adhesion and hardness. Polishing after 24 hours of curing showed less bacterial adherence on the composite surface, regardless of the polishing treatment performed(p<0.01). Polishing with SOF-LEX(Group-2) had the lower bacterial adherence than SUPER-SNAP (Group-3), Control group (Mylar matrix strip) promoted the lowest bacterial adhesion on the surface composites. Micro hardness of composite was lowest in Mylar matrix group. Immediate polishing procedure showed lower microhardness values as compared to polishing that was delayed for 24hours for both polishing groups. SOF-LEX system can be used for chairside polishing of composite restorations in clinic and delayed finishing and polishing of composite shows better surface microhardness values.

The Influence of Cement Removal Techniques on In Situ Bacterial Adhesion and Biodegradation at the Marginal Interface of Ceramic Laminates.

This in situ study aimed to analyze the influence of different resin cement removal techniques on bacterial adhesion and biodegradation at the marginal interface of ceramic laminates. Eighty feldspathic ceramic (F) blocks were prepared and cemented onto bovine enamel slabs (7×2.5×2 mm). Excess cement was removed using a microbrush (MBR), a scalpel blade (SCP), or a Teflon spatula (TSP). For the biodegradation analysis, 40 disc-shaped resin cement specimens were prepared (7×1.5 mm) using a Teflon mold. The specimens were randomly allocated into two groups: (1) No finishing procedure (only Mylar strip), and (2) with finishing and polishing procedures using the Jiffy system (Ultradent, South Jordan, UT, USA) (n=20). The in situ phase consisted of using an intraoral palatal device by 20 volunteers for 7 days. Each device contained five cylindrical wells (8×3 mm), where three dental blocks and two cement specimens were included in the wells. Surface roughness (Ra) was measured using a contact profilometer. A micromorphological analysis was performed under a stereomicroscope and a scanning electron microscope. Bacterial adhesion was quantitated based on the number of colony-forming units (CFU/mL) and their biofilm development potential. The cement removal techniques directly affected surface roughness at the marginal interface (p<0.001), and the SCP technique produced higher mean roughness, regardless of the surface area analyzed. Surface polishing protected cement specimens from further biodegradation (p=0.148). There were no differences in CFU counts between the groups after the in situ phase (p=0.96). All specimens showed CFU with a strong ability to develop a biofilm. The techniques used for cement removal increased the surface roughness of ceramic laminates, particularly SCP, but they did not affect bacterial adhesion at the marginal interface. Surface polishing of the resin cement is recommended to mitigate biodegradation.

THE EFFECT OF GLYCERINE GEL AND MYLAR STRIP ON THE MARGINAL ADAPTATION OF COMPOSITE - LUTED INLAYS: AN IN VITRO RESEARCH

Background: Composite – luted ceramic inlays were one of the top choices for restorations of anterior and posterior teeth because of high aesthetic, good marginal adaptation and controllable anatomy and lateral contact. If the luting composite was exposed to air condition during polymerization, the presence of oxygen would interfere with polymerization of the adhesive surface layer, adversely affecting the prognosis of restorations. Therefore, it is very essential to evaluate different margin - treating techniques to prevent the formation of an oxygen - inhibited layer during the polymerization of composite resin materials. Objectives: The aim of this study was to examine the effectiveness of glycerine and Mylar strip on the marginal adaptation of composite - luted inlays. Methods: Thirty class II cavities were prepared on extracted human permanent premolars, randomly divided into three groups: group 1: e.max Press indirect inlays luted by Variolink II were polymerized in air; group 2: inlays were polymerized after applying glycerine on the restoration margins; group 3: inlays were covered by Mylar strip before light polymerization. To remove the oxygen - inhibited layer, the inlays were brushed with acetone. The clinical evaluation and computerized quantitative marginal analysis under digital microscope were carried out before and after applying acetone. Results: Statistical analysis revealed significant difference between the polymerization with and without the use of glycerine gel, specifically, the inlay margins of group 2 showed better marginal adaptation than group 1 did (p &lt; 0.001). Meanwhile, there was no statistical difference between group 2 and 3 in marginal quality of restorations. Conclusions: Oxygen-initated inhibition during polymerization can be prevented by the application of glycerine gel and Mylar strip to the surface of composite resin materials Key words: IPS e.max Press inlay, class II restoration, marginal adaptation, glycerine gel, Mylar strip.

The effect of contemporary finishing and polishing systems on the surface roughness of bulk fill resin composite and nanocomposites.

To evaluate the effects of various finishing and polishing (F/P) systems regarding the surface roughness (Ra ) value of two nanocomposites and a bulk fill resin composite. Three resin composites (Filtek Z550, Filtek Ultimate Body, Filtek Bulk Fill Posterior) were tested. Forty disk-shaped specimens of each material were cured under Mylar strip and then randomly divided into four subgroups according to the F/P method (n=10): Control, Sof-Lex Spiral Wheels, Astropol, and Clearfil Twist Dia. Ra values was measured and the surfaces were examined under scanning electron microscope. The data were analyzed by generalized linear models (p < 0.05). The Filtek Bulk Fill Posterior had the highest Ra value while Filtek Ultimate Body was the resin composite with the lowest roughness (p < 0.05). Considering the average Ra values after polishing, while the lowest Ra in all groups was obtained with the control group, the Clearfil Twist Dia showed similar Ra to the control group (p > 0.05). The samples polished with Sof-Lex Spiral Wheels had the highest Ra (p < 0.05). In addition to the resin composite type, the F/P technique greatly affected the Ra value of resin composite. The nanocomposites exhibited with the lowest Ra compared to the bulk fill resin composite after F/P. It was observed that the diamond containing-polishing system created smoother surfaces than the aluminum oxide containing- and silicon carbide containing-polishing systems. In terms of Ra , the nanocomposites exhibited better performance than the bulk fill resin composites. Nowadays, newly developed polishing systems containing diamonds can be successful at a comparable level to existing polishing systems. For this reason, these systems are preferable for polishing both nanocomposites and bulk fill resin composites.

BESİN TAKLİDİ SIVILARIN SELF ADEZİV REZİN SİMANLARIN RENK DEĞİŞİMİNE ETKİSİ

Amaç: Bu çalışmada besin taklidi sıvıların dört farklı self adeziv rezin simanın renk değişimine etkisinin incelenmesi amaçlanmıştır. Yöntem: Çalışmada dört farklı self adeziv rezin simandan (Zirconite, HighBond, Zenitcem, ve Totalcem) 80 adet örnek hazırlandı. Disk şeklindeki kalıplara yerleştirilen simanlar şeffaf bantla kapatıldıktan sonra üretici firma talimatları doğrultusunda ışıkla polimerize edildi. Her bir simandan hazırlanan örnekler distile su, heptan, sitrik asit ve etanol sıvılarında bekletilmek üzere dört alt gruba ayrıldı (n=5). Test örnekleri oda sıcaklığında 7 gün boyunca besin taklidi sıvılarda bekletildi. Örneklerin başlangıç ve 7. günlerde renk ölçümleri spektrofotometre ile gerçekleştirildi ve ΔE00 değerleri hesaplandı. Veriler, iki yönlü ANOVA ve Tukey HSD testleri kullanılarak istatistik olarak analiz edildi (α=0,05). Bulgular: Totalcem grubu hariç tüm materyaller için etanolün diğer sıvılara kıyasla anlamlı derecede daha yüksek renk değişikliğine sebep olduğu gözlendi (P<0,05). Totalcem materyalinde ise en yüksek renk değişiminin heptan grubunda gerçekleştiği, ancak heptan ve etanol grubu arasında istatistik olarak anlamlı farkın gözlenmediği bulundu (P>0,05). Distile suyun, Zirconite’in rengi üzerine Totalcem’e kıyasla daha fazla etkisinin olduğu tespit edildi (P<0,05). Sitrik asitte bekletilen siman grupları arasında anlamlı fark bulunmadı (P>0,05). En yüksek renk değişimi değeri etanol sıvısında bekletilen Highbond grubunda (4,27 ±2,34) gözlenirken, en düşük renk değişimi değeri ise distile suda bekletilen Totalcem grubunda (0,34±0,07) tespit edildi. Sonuç: Besin taklidi sıvıların self adeziv rezin simanların renk değişimi üzerine farklı etkilerinin olduğu bulundu. Genel olarak etanolün self adeziv rezin simanlarda daha fazla renk değişikliğine neden olduğu gözlendi. Anahtar Kelimeler: Besin taklidi sıvılar; renk; rezin simanlar Effect of food-simulating liquids on the color change of self-adhesive resin cements Abstract Objective: The aim of present study was to evaluate the effect of food-simulating liquids on the color change of the four different self-adhesive resin cements. Materials-Methods: In this study, eighty specimens of four different resin cements (Zirconite, HighBond, Zenitcem, and Totalcem) were prepared. The materials were placed into disc-shaped molds covered using mylar strips, then cured in accordance with the manufacturers’ recommendations. The specimens of each cement were divided into four subgroups as (n=5): distilled water, heptane, citric acid, and ethanol. The specimens were kept in the solutions for 7 days at room temperature. Before and after 7 days of storage color measurements were performed by using spectrophotometer and ΔE00 values were calculated. Data were analyzed with two-way ANOVA and Tukey HSD tests (α=0.05). Results: For all materials except Totalcem, it was observed that ethanol caused significantly higher color change than other liquids (P<0.05). However, in Totalcem the highest color change was observed in heptane group, but no statically significant difference was found between heptane and ethanol groups. It was observed that distilled water was more effective on the color change of Zirconite than Totalcem (P<0.05). There was no statically significant difference among the cement groups after storing in citric acid solution (P> 0.05). The highest color change value was found in HighBond (4.27 ± 2.34) which was stored in ethanol solution, while the lowest color change value was observed in Totalcem (0.34 ± 0.07) stored in distilled water. Conclusion: It was found that food-simulating liquids had different effects on the color change of self-adhesive resin cements. In general, it was observed that ethanol caused more color change in self-adhesive resin cements. Key Words: Color; food-simulating liquids; resin cements

Surface evaluations of a nanocomposite after different finishing and polishing systems for anterior and posterior restorations.

This study aims to evaluate the effects of different finishing and polishing (F/P) systems on gloss and surface morphology of a new nanocomposite. Thirty discs of Filtek Universal Restorative material (3 M, ESPE) were prepared and divided into six groups (n = 5). Group A and B followed F/P protocols for anterior restorations, whereas Group C and D for posterior ones. Group E represented the control (covered by Mylar strip) and Group F represented the nanocomposite placement by means of clinical hand instruments; Groups E and F did not undergo F/P procedures. Among the polished groups, Group B showed the highest values (68.54 ± 7.54 GU), followed by Group A and D (46.87 ± 5.52 GU; 53.76 ± 2.65 GU). Finally, Group C (37.38 ± 4.93 GU) displayed the lowest results. Overall, Group E showed the highest gloss values (93.45 ± 8.27 GU), while Group F presented the lowest ones (1.74 ± 0.64 GU). Surface analysis revealed that Group A, C, and D displayed a smooth surface. Group B showed the lowest irregularities. Group E exhibited the most uniform superficial morphology. On the other hand, Group F displayed the most irregular one. In conclusion, using the tested material, only two protocols achieved appropriate gloss values. Then, clinicians might use the protocols of Group B and Group D, for anterior and posterior restorations, respectively.

Surface roughness of composite resins submitted to three different finish and polish systems

Objective: This study aimed to evaluate the in vitro performance of three different finishing and polishing systems, concerning providing better surface smoothness. Materials and methods: 2x4 mm specimens were made with 6 composites: Filtek Z250, Classic Herculite, Opalis, Filtek Z350, Zirconfilll and Estelite Omega, which were subsequently divided into four groups according to a different finishing system (Sof-Lex, OptiDisc, Praxis and Control). After polishing, twelve specimens were distributed to each of the six resins studied, making a total of 72 samples (n = 3), which had their roughness evaluated by a contact roughnessmeter. The Kruskal-Wallis test and Dunn's post-test with Bonferroni adjustment were used to search for significant differences. Values ​​were considered significant when p &lt;0.05. Results: The roughness values ​​for finishing systems showed statistical differences between OpiDisc x Praxis (p = 1,000), OpiDisc and Sof-lex (p = 0.605) and Control and all systems (p &lt;0.0001). There was no statistical difference when analyzing the combination of resin x system. The Mylar strip provided surface quality. Conclusions: The size, composition and shape of the filler influenced the surface. Sof-lex and Praxis showed similar results, thus being a good choice for polishing. Clinical Relevance: This study aimed to help the professional in the choice of a better material in the polishing step.

The Effect of Different Polishing Systems on the Surface Roughness of Nanocomposites: Contact Profilometry and SEM Analyses.

The aim of this study was to evaluate the effects of different polishing systems on the surface roughness of different nanocomposite resins using various analysis methods. Three types of nanocomposite resins were investigated in this study: supra-nanohybrid (Estelite Asteria), nanohybrid (GrandioSo), and nanoceramic composite resins (Ceram-X Spheretec One). Forty-eight disc-shaped specimens (4 mm in diameter, 2 mm in thickness) were fabricated using a Teflon mold and divided into four groups according to the different polishing systems (n=12). All specimens were processed with one of the following methods: Mylar strip (control), one-step polishers (Opti1step), two-step polishers (Clearfil TwistDia), or multistep polishers (Sof-Lex XT Pop-on). The surface roughness (Ra, μm) was measured by contact profilometry (Mahr, Marsurf PS1) (n=10) and scanning electron microscopy (SEM) (Thermo Fisher Scientific, Phenom XL) at 400× magnification (n=2). The data were statistically analyzed using Kruskal-Wallis and Bonferroni correction tests (p<0.05). In addition, the surface morphology and elemental content were examined by SEM and energy dispersive x-ray spectroscopy (EDS) analyses. Under SEM evaluation, in terms of the polishing systems, there were no significant differences in the surface roughness for supra-nanohybrid composite resin (p>0.05). The multistep polishers created lower surface roughness than the one-step polishers for nanohybrid and nanoceramic composites. In terms of the composite resins, supra-nanohybrid composite exhibited lower surface roughness than nanohybrid composite for all polishing systems (p<0.05). The SEM observations confirmed the surface roughness measurements related to the surface morphology. One-step and two-step polishers created porosity on the surface of nanohybrid and nanoceramic composites. EDS analysis indicated the elemental composition of the particles in the porous zones was quite close to diamond abrasives and glass fillers.

Comparison of Different Finishing-Polishing Systems on Surface Roughness of Nanofilled Composite Resin

Aim: This in vitro study was conducted to evaluate the effectiveness of different finishing and polishingsystems on the surface roughness of nanofilled (Z350XT) composite resin.Materials and Methods: A total of 60 disc-shaped samples were prepared in composite resin usingstandardized cylindrical metal mold (10 mm in diameter and 2 mm thick). The specimens were randomlydivided into six groups (n= 10): Group 1- Mylar strip, Group 2- Sof-Lex polishing system, Group 3- SuperSnap polishing system, Group 4- OptiDisc polishing system, Group 5- Opti1Step polishing system andGroup 6- OneGloss polishing system. The average surface roughness (Ra) of each specimen was measuredthree times and the mean Ra values were determined using a surface profilometer.Results: According to the one-way analysis of variance, surface roughness was in the following order:Mylar strip < Super Snap polishing system < OptiDisc polishing system < Opti1Step polishing system <SofLex polishing system < OneGloss polishing system. This difference in surface roughness was statisticallysignificant (P < 0.05) in all the six experimental groups.Conclusion: Composite surface roughness depends on the composition, number of steps and flexibility ofthe finishing and polishing system used.

Comparative Evaluation of Flexural Strength of Two Newer Composite Resin Materials: An in Vitro Study

Objective: To evaluate in vitro the flexural strength of two newer composite resin materials . Material and Methods: Twenty-four samples were equally divided into two groups: G1 - Brilliant EverGlow and G2: Brilliant NG. The rectangular blocks of 25 mm in length, 2 mm in width and thickness were prepared from two composite materials. Blocks were created by applying composites to a customized split mold and formed between two parallel glass plates. Before light-curing, blocks were covered with Mylar strips and rinsed for 10 seconds in water. Subsequently, they were stored in distilled water for 24 hours at 37oC and 100% humidity before testing. Each sample was placed within a suitable framework of aluminum. The length of gap between the support was 21 mm and the speed of crosshead at 1 mm/minute. The data were subjected to an independent t-test. The level of significance was set at p <0.05. Results: A less flexural strength was observed in G1 (77.43 Mpa) compared to G2 (118.70 Mpa) (p<0.001). Conclusion: Universal nanohybrid composite resin material was found to have greater flexural strength than universal submicron hybrid composite material.

Comparative Evaluation of Surface Roughness of Resin- Modified Glass Ionomer and Glass Hybrid Restorative Materials Simulated by Tooth Brushing: An in-Vitro Study

Objective: To compare the effect of tooth brushing on surface roughness of Resin-Modified Glass Ionomer Cement (RMGIC; GC Gold label 2LC Light Cured Universal Restorative) and Glass Hybrid (GH; GC EQUIA SYSTEM- EQUIA Forte™ Fil and EQUIA Forte™ Coat) restorative material at 1- and 3-months interval simulated by tooth brushing . Material and Methods: RMGIC and GH material specimens (20 each) were prepared according to manufacturer instructions in 10 mm × 2 mm dimensions using a mylar strip. A specially designed toothbrush simulator was used along with Oral B Pro 2 2000N powered toothbrush and Colgate Total dentifrice (Colgate-Palmolive India limited; Relative dentin abrasivity - RDA: 70 - Low abrasive) to perform brushing strokes. Specimens were subjected to surface roughness analysis before and after simulated tooth brushing at baseline, 1, and 3 months. Results: The intragroup comparison was done using repeated-measures ANOVA. Intergroup comparisons were done using an independent sample t-test and General Linear Model (ANCOVA). Surface roughness increased from baseline through 3 months in both RMGIC and GH groups. The mean surface roughness in RMGIC group was significantly higher than GH group at baseline 1 and 3-months, respectively (p<0.001, <0.001, and <0.001). Interaction between group and baseline surface roughness was not significant (p=0.466). The estimated marginal means were significantly higher in RMGIC than GH group (p=0.008) . Conclusion: The surface roughness of both RMGIC and GH restorative increased from baseline to 1 month and 3 months after the simulated toothbrushing protocol. GH exhibited significantly lower surface roughness than RMGIC at all the tested intervals.

Effect of different placement techniques on color stability and surface roughness of resin composites

Abstract Introduction Longevity and clinical success of dental restorations can be influenced by many factors during the restorative procedures. Objective This study aimed to evaluate the influence of different placement techniques on color stability and surface roughness of two resin composites. Material and method The groups of specimens (n=10) were divided according to resin composite (FiltekTM Z250 XT and FiltekTM Z350 XT) and placement technique: Mylar strip, spatula, dry brush, modeling liquid, and surface sealant. Color stability and surface roughness were accessed using a spectrophotometer (CIELab color space) and a rugosimeter (standard cutoff of 0.8 mm), respectively, after water storage. Subsequently, the specimens were immersed in coffee for 48 h and final color was measured. The data were analyzed using ANOVA and the Tukey’s post hoc test (α=5%) and the correlation between surface roughness (Ra) and color change (∆Eab) was assessed using the Pearson’s correlation coefficient. Result The different placement techniques influenced Ra and ∆Eab on both resin composites. The groups treated with surface sealant showed greater difference in ∆Eab for both resin composites. The FiltekTM Z250 XT resin showed greater color stability compared with the FiltekTM Z350 XT resin regardless of the placement technique used. Ra of each placement technique was similar among the resin composites except for the FiltekTM Z350 XT modeling liquid group, which presented lower Ra values compared with those of FiltekTM Z250 XT. A correlation between Ra and staining was identified (p=0.268). Conclusion Color stability and Ra are influenced by different placement techniques.

The effect of the polishing procedure and surface sealant application on the fluoride release of different restorative materials

Aim: The aim of this study is to evaluate the effect of the polishing procedure and surface sealant application on the fluoride release of different restorative materials. Materials and Methods: The study groups composed of five different restorative materials: Beautifil II, GCP Glass Fill, Amalgomer CR, Zirconomer, and Fuji IX GP. 30 disk-shaped specimens (8 mm diameter × 2 mm thickness) were prepared from each material. Each group was divided into three subgroups according to the finishing procedure: Mylar strip, polishing with Super-Snap discs, polishing with Super-Snap discs followed by G-Coat Plus application. The amount of fluoride released was measured using a fluoride ion-selective electrode and ion analyzer after 24 h followed by measurement on days 3, 7, 15, 21, and 28. Surface analysis of the materials was performed with scanning electron microscopy and energy-dispersive X-ray spectroscopy (EDS). The data were statistically analyzed using repeated measure analysis of variance and the least significant difference test (P = 0.05). Results: The highest amounts of fluoride release were found during the first 24 h for all materials. The amounts of fluoride release revealed a significant decrease from day 1 to day 28 for each group (P 0.05). According to EDS data, the most percentage of oxygen was found in all materials. Conclusions: It might be concluded that polishing promoted a significant increase of fluoride release on glass ionomer-based materials, and the fluoride release of the restorative materials was not affected by applying G-Coat Plus.

Effect of the polishing procedure and surface sealant application on fluoride release

Objective: This study aimed to assess the effect of the polishing procedure and surface sealant application on the fluoride release of restorative materials. Material and Methods: The groups were consisted of using five different restorative materials were employed: Beautifil II, GCP Glass Fill, Amalgomer CR, Zirconomer and Fuji IX GP. 30 disk-shaped specimens (8x2 mm) were prepared from each material. Each group was subdivided into three groups considering finishing procedures: Mylar strip, polishing with Super-Snap discs, G-Coat Plus application after polishing with Super-Snap discs. The amount of fluoride released into distilled water was measured using a fluoride ion-selective electrode and ion analyzer after 24 hours, followed by measurement on days 3, 7, 15, 21, and 28. Surface analysis of the materials was performed with SEM (Scanning Electron Microscopy) and EDS (Energy Dispersive X-ray Spectroscopy). The data were statistically analyzed using two-way repeated measure ANOVA and LSD test (p=0.05). Results: The highest amount of fluoride released was measured after the first 24 h for all materials. Beautifil II released less fluoride than other materials in all measurement periods (p&lt;0.05). After polishing, the amount of fluoride released from all materials except Beautifil II increased (p&lt;0.05). The application of G-Coat Plus did not impact the amount of fluoride release of any materials (p&gt;0.05). EDS analysis showed the most percentage of oxygen in all materials. Conclusion: The polishing procedure might induce an increase in fluoride release of glass ionomer-based materials, and the application of G-Coat Plus cannot affect the amount of fluoride release. Keywords Energy dispersive x-ray spectroscopy; Fluoride; Glass ionomer cement.

Effect of Different Polishing Systems on the Surface Roughness and Gloss of Novel Nanohybrid Resin Composites.

Objectives To evaluate the surface roughness and gloss of three nanohybrid resin composites after polishing with three different polishing systems. Materials and Methods A total number of 112 disc specimens (10 × 3 mm) were prepared from nanohybrid—Empress Direct (ID), Grandio (GR), Filtek Z350 (Z350) and a microhybrid resin composite restorative materials—Filtek Z250 (Z250). Following 24-hour storage in 37°C distilled water, each composite group ( n = 28) was assigned into four groups ( n = 7) according to finishing/polishing (F/P) system: Mylar strip, Optrapol, Politip, and Sof-Lex (SL). The surface roughness (Ra, mm) was measured by a novel three-dimensional method using an image analysis software attached to an environmental scanning electron microscope. A glossometer was used to measure the surface gloss. Results Statistical analysis used was ANOVA test. Two-way Anova test revealed that the “type of composite” and “F/P techniques” had a significant effect on both surface roughness and gloss of the tested resin composite materials ( p < 0.05). Tukey’s post hoc test showed that ID, GR, and Z350 revealed lower surface roughness and higher surface gloss than Z250 within the same polishing system ( p < 0.05). Sof-Lex polishing discs produced the lowest surface roughness and highest surface gloss values compared with Optrapol and Politip ( p < 0.05). Conclusion The tested F/P systems provided comparable surface roughness and gloss for nanohybrid composites. The Sof-Lex system provided the best surface roughness and gloss for nanohybrid composites.

Effect of Multiple Use and Sterilization of Single-Step Polishing Systems On the Surface Roughness of Resin Composite

Aim: To evaluate the effect of multiple use and sterilization of Single-Step polishing tips on the surface roughness of resin composite. Materials and Methods: Eighty Nano-filled resin composite discs were prepared and cured against Mylar strip. Except for the control group, samples were wet ground against 600-grit SC paper, then divided into 3 groups (n = 25), Group D (Dimanto® - VOCO), Group G (PROGLOSS™ - KaVo Kerr), and Group O (OptraPol® - Ivoclar Vivadent). Five tips from each system were autoclaved and used for sample polishing, and this process was repeated for 5 successive Reuse/Sterilization cycles (S1 - S2 - S3 - S4 - S5). Samples were scanned using SEM, scans were analysed by Gwyddion 2.53 Image Analysis Software to attain surface roughness average Ra data, which were statistically analysed by two-way ANOVA and Tukey Post Hoc test. Results: Single-step polisher system, reuse/sterilization cycles and their interaction were found to have a statistical significant effect on the Ra of the tested groups. Control group had the least Ra. All S1 Groups and two of S2 groups, showed higher Ra without statistically significant difference between them or between them and the control. The following cycles showed a progressive increase in Ra values, with GS4, GS5, DS5, and roughened groups, showing the highest Ra without statistically significant difference between them. Conclusion: Single-step reusable polishing tips can polish resin composite back to matrix-set Ra values within the first and second reuse/sterilization cycles, afterwards the tips' polishability decreases significantly and becomes system dependent.