Clinical Performance of Bulk-Fill Resin Composite Restorations Using the United States Public Health Service and Federation Dentaire Internationale Criteria: A 12-Month Randomized Clinical Trial

Objective This study was aimed to compare the 12-month clinical performance of two full-body bulk-fill resin composites Filtek bulk fill/3M ESPE (FBF) and Tetric EvoCeram bulk fill/Ivoclar Vivadent (TBF) and a conventional microhybrid resin composite Filtek Z250/3M ESPE (Z250) using the modified the United States Public Health Service (USPHS) and Federation Dentaire Internationale (FDI) criteria. Also, the agreement between the two evaluation criteria was evaluated at baseline and after 12 months of follow-up. Materials and Methods A total of 138 class I and II restorations were placed in posterior teeth (split-mouth design) of 46 volunteers following manufacturer’s instructions and bonded with a self-etching bonding agent (Clear fill SE Bond/Kuraray). The restorations were evaluated at baseline and after 12 months of follow-up by three previously calibrated dentists (Cohen’s K = 0.84). Statistical Analysis Fisher’s exact test and Pearson’s Chi-squared test were used to evaluating the homogeneity of distribution of the clinical characteristics. Friedman’s test was applied to evaluate differences among the resin composites. The results obtained for the USPHS and FDI criteria at the different observation times were compared using the Wilcoxon test. A level of significance of 0.05 was adopted for all tests. Results After 12 months (recall rate, 78.3%, n = 36 patients), the overall success rate was 99.07% for both criteria. Only one failed restoration (0.93%) was detected for each system during follow-up in the TBF group. Conclusion The bulk-fill resin composites showed satisfactory clinical performance compared with conventional resin composite after 12 months. The percentage of the acceptable scores was significantly higher for the USPHS criteria, due to discrepancies in the score description for each criterion.