Increasing the longevity of restorations by minimal intervention: a two year clinical trial

Abstract

This investigation assessed the effectiveness of alternative treatments for the replacement of amalgam and resin-based composite restorations. Sixty-six patients (age 18 to 80 years, mean = 26.6) with 271 (amalgam [n = 193] and resin-based composite [n = 78]) defective restorations were randomly assigned to one of five different treatment groups: A) Repair (n = 27); B) Sealing of margins (n = 48); C) Refurbishing (n = 73); D) Replacement (n = 42) and E) Untreated (n = 81). USPHS/Ryge criteria were used to determine the quality of the restorations. Two calibrated examiners (Cohen’s Kappa 0.74) assessed the restorations independently at the beginning of the study (baseline) and at 2 years after treatment using seven parameters from the USPHS/Ryge criteria (Marginal Adaptation, Anatomic Form, Roughness, Marginal Stain, Occlusal Contact, Secondary Caries and Luster).

RESULTS: Two-hundred and fifty-six restorations (178 amalgam and 78 resin-based composite) were examined at the 2-year recall exam. The sealing of marginal defects showed significant improvements in marginal adaptation (P < .05). Refurbishing of the defective restorations significantly improved anatomic form (P < .0001), luster (P < .016), marginal adaptation (P < .003) and roughness (P < .0001). The repair significantly improved anatomic form (P < .002) and marginal stain (P < .002). Replacement showed significant improvements for all parameters (P < .05). The Untreated group showed significant deterioration on marginal adaptation (P < .013).

CONCLUSIONS: The 2-year recall examination showed that sealant, repair, and refurbishing treatments improved the clinical properties of defective amalgam and resin-based composite restorations by increasing the longevity of the restorations with minimal intervention.