ABSTRACT
PURPOSE: To evaluate sealed amalgam and resin-based composite restorations after 12 years to determine whether sealing minor defects (micro-repairs) enhanced the longevity of restorations. METHODS: 34 subjects aged 18-80 were recruited. This sample group underwent 137 restorations, including 51 resin-based composite (RC) and 86 amalgam (AM) restorations. Existing restorations with localized, marginal defects were assigned to one of two groups: (a) the Sealing group (n=48, 27 AM; 21 RC) or (b) the Control group (n=89, 59 AM; 30 RC). The quality of each restoration was scored according to the modified USPHS criteria by two examiners at the beginning of the study and after 1-5, 10, and 12 years. Kaplan Meier survival curves were created and a Cox regression was applied to investigate survival variables. Mantel Cox, Wilcoxon, and Friedman tests were performed for comparisons within groups. RESULTS: After 12 years, no statistically significant differences were observed for the variables "restorative material" (P= 0.538) or "sealing yes/no" (P= 0.136) with respect to the longevity of the restorations. All groups behaved similarly with regard to marginal adaptation, secondary caries, and tooth sensitivity (P≥ 0.05). Cumulatively, after a 12-year observation period, sealing minor restoration defects did not affect the longevity of the restorations. CLINICAL SIGNIFICANCE: Sealing minor marginal defects for resin composites or amalgam restorations did not affect their longevity. This intervention may be considered over-treatment for patients with low-to-medium risks for developing dental caries.