A randomized 10-year prospective follow-up of Class II nanohybrid and conventional hybrid resin composite restorations.

PURPOSE: To evaluate the 10-year durability of a nanohybrid resin composite in Class II restorations in a randomized controlled intraindividual comparison with its conventional hybrid resin composite predecessor. MATERIALS AND METHODS: Each of 52 participants received at least two Class II restorations that were as similar as possible. The cavities were chosen at random to be restored with a nanohybrid resin composite (Excite/Tetric EvoCeram (TEC); n=61) and a conventional hybrid (Excite/Tetric Ceram (TC); n=61). The restorations were evaluated with slightly modified USPHS criteria at baseline and then annually for 10 years. The overall performance of the experimental restorations was tested after intra-individual comparison and their ranking was tested using Friedman's two-way ANOVA. The level of significance was set at 5%. RESULTS: Four patient drop-outs with 8 restorations (4TEC, 4TC) were registered during the follow-up. A prediction of the caries risk showed that 16 of the evaluated 52 patients were considered as high risk patients. In total, 22 restorations, 11 TEC (3 premolars, 8 molars) and 11 TC (3 premolars, 8 molars) restorations failed during the 10 years. The main reason for failure was secondary caries (50%). 63% of the recurrent caries lesions were found in high caries risk participants. The overall success rate at 10 years was 80.7%, with an annual failure rate of 1.9%. No statistically significant difference was found in the overall survival rate between the two investigated resin composites. CONCLUSION: The nanohybrid and the conventional hybrid resin composite showed good clinical effectiveness in extensive Class II restorations during the 10-year study.