Estudo clínico controlado, aleatorizado, duplo-mascaramento, do desempenho de uma resina composta à base de silorano em restaurações de classe II

Abstract

The aim of this randomized, double-blind, controlled study was to compare the clinical performance of a silorane-based resin composite with a methacrylate-based resin composite in Class II restorations after 18-month follow-up. After obtaining informed consent, 33 patients received 100 direct Class II composite resin restorations (n=50) that were randomly allocated into a test group (Filtek P90R /Adhesive System - 3M ESPE) or control group (Filtek P60R /Adper SE PlusR - 3M ESPE). After one week, the restorations were finished and polished. A singleoperator performed all the restorative procedures. Two calibrated examiners (weight kappa . 0.7) assessed the restorations at the baseline and after 18 months, according to modified United States Public Health System (USPHS) criteria. The parameters analyzed were marginal discoloration, marginal integrity, surface texture, anatomic form, postoperative sensitivity, secondary caries, proximal contact andradiographic aspect. Data were analyzed with Mann-Whitney U-test, Wilcoxon signed Rank, Kaplan-Meier statistics and Cox regression analysis (¿=0.05). At 18-month follow-up, 90% of the restorations were evaluated. The marginal integrity of the test group was significantly worse than that of the control group (p=0.035). The analysis of each material over the time showed significant worsening in the control group formarginal discoloration (p=0.046) and surface texture (p=0.005). For the test group, there was significant worsening for marginal discoloration (p=0.025), marginal integrity (p=0.046) and surface texture (p=0.005). There was no significant difference between the survival rates observed for the test (92%) and the control (98%) groups (p=0.185). There was no significant effect of the restorative system (p=0.246), the tooth type (p=0.673) nor the number of restored surfaces (p=0.402) on the survivalcurves. The clinical performance of silorane-based composite resin was similar to the well-known methacrylate systems, but the marginal integrity was worse for the silorane system. The restorations lost quality for marginal discoloration, marginal integrity and surface texture criteria, but remained acceptable after 18 months. The use of silorane based system presents no advantages compared to methacrylatebased systems to restore Class II cavities.