Does refurbishing composites lead to short-term effects or long-lasting improvement?

Purpose: To evaluate the clinical performance of refurbished resin composite restorations compared to untreated (negative control) restorations over a period of 10 years. Methods: 26 subjects (having a total of 52 composite restorations) were recruited. All restorations in the refurbished group showed clinical features rated bravo according to modified USPHS criteria. Untreated restorations were those that had been deemed acceptable (alpha or bravo rated); these were used as controls. Two examiners performed assessments at baseline and during the 5^th and 10^th years after the intervention. Wilcoxon tests were performed for within-group comparisons, Friedman tests were used for multiple within-group comparisons, and Mann Whitney tests were used for between-groups comparisons. Kaplan-Meier survival curves were calculated, and the Mantel-Cox test was used to compare curves. P < 0.05 was considered statistically significant. Results: In both groups, 10-year scores were significantly different from baseline scores in all clinical parameters except secondary caries. There were no statistically significant differences in the survival analysis of groups (log-rank test, P= 0.376). Refurbishing treatment improved the anatomy, roughness, luster, and marginal adaptation of restorations with a short term effect, with most properties rated acceptable after 10 years of clinical service. The clinical characteristics were similar for all groups at the 10^th year.