A double-blind randomized clinical trial of a silorane-based resin composite in class 2 restorations: 18-month follow-up.

PURPOSE: To compare the clinical performance of a silorane-based with a methacrylate-based restorative system in class 2 restorations after an 18-month follow-up. METHODS: This randomized, double-blind and controlled study included 33 subjects receiving 100 direct resin composite restorations that were completely randomized to silorane-based group (Filtek P90/Silorane System Adhesive - 3M ESPE) or methacrylate-based group (Filtek P60/Adper SE Plus - 3M ESPE). The restorative system was determined by chance using a coin toss until 50 units for each group were completed. Each subject contributed with one to seven restorations. A single operator performed all of the restorative procedures. Two calibrated examiners (kw > or = 0.7) assessed the restorations at baseline and after 18 months according to modified United States Public Health System (USPHS) criteria. The data were analyzed with Mann-Whitney U-test, Wilcoxon signed rank and Kaplan-Meier survival curves (alpha = 0.05). RESULTS: After 18 months, 88 restorations were evaluated, and five unacceptable restorations were observed. Proximal contact loss was the main reason for failure (three) followed by composite fracture (two). The marginal integrity of the silorane-based group was significantly worse than that of the methacrylate-based group (P= 0.035). Comparing baseline to 18-month evaluations, the silorane-based group showed significant differences for marginal discoloration, marginal integrity and surface texture (P < 0.05); and the methacrylate-based group differed significantly for marginal discoloration and surface texture (P < 0.05). Combined survival rate for both groups together was 95%. No statistically significant difference was found between methacrylate-based (98%) and silorane-based (92%) overall survival rate (Log rank test; P = 0.185).

The short-term clinical performance of a silorane-based resin composite in the proximal contacts of class II restorations.

AIM: The aim of this randomized clinical trial was to compare the proximal contact of a silorane-based resin composite with a conventional methacrylate-based resin composite in class II restorations after a 6 months follow-up period. MATERIALS AND METHODS: After obtaining informed consent, 33 patients were randomly allocated into a test group (Filtek P90/Adhesive System-3M ESPE) or control group (Filtek P60/ Adper SE Plus-3M ESPE), and 100 direct resin composite restorations (n = 50) were placed. A single operator performed the cavities and restorations. After rubber dam placement, a metal matrix and wooden wedge were placed. The restorative systems were applied according to the manufacturer's instructions. After 1 week, the restorations were finished and polished. The proximal contacts were assessed blindly and independently by two calibrated examiners (kW = 0.8) at the baseline and after 6 months according to a three-step grading criteria. Data were analyzed with the Mann-Whitney U-test and Wilcoxon signed Rank tests (a = 0.05). RESULTS: After 6 months, 96% of the restoration contacts were present for evaluation. The frequencies of restorations classified as Bravo in control and test groups were 6 and 8% at the baseline, and 6.25 and 12.75% after 6 months. No significant difference was found between the restorative materials (p > 0.05; Mann-Whitney U-test) neither between baseline and 6 months period (p > 0.05; Wilcoxon signed Rank tests). CONCLUSION: Both materials performed satisfactorily over 6 months follow-up period. CLINICAL SIGNIFICANCE: The short-term clinical performance of a silorane-based resin composite in the proximal contacts of class II restorations was similar to the well-known methacrylate-based resin composite.