The most common treatment in general dental practice is the replacement of restorations affected by secondary caries or marginal deficiencies. Alternative treatments to replacement of defective restorations, such as marginal sealing, refurbishment and repair, have demonstrated improvement of their clinical properties with minimal intervention. The aim of this clinical study was to estimate the median survival time (MST) of marginal sealing, repair and refurbishment of amalgam and resin-based composite restorations with localized defects as a treatment to increase the restoration longevity. A cohort of 66 patients, with 271 class I and II restorations clinically diagnosed with localized defects was longitudinally assessed. Each restoration was assigned to one of the following 5 groups: Marginal Sealing (n=48), Refurbishment (n=73), Repair (n=27), Replacement (n=42), and Untreated (n=81). Two calibrated examiners assessed the restorations at baseline and annually during 4 years, using the modified Ryge criteria: marginal adaptation, anatomic form, roughness, secondary caries and luster. Fifty-two patients with 208 restorations were assessed after 4 years; the distribution of restorations in the groups was as follows: Marginal Sealing (n=36), Refurbishment (n=63), Repair (n=21), Replacement (n=28) and Untreated (n=60). Kaplan Meier test indicated that the Sealed margins group showed the lowest MST while the Repair group showed the highest MST for restorations examined after 4 years of follow up. Defective amalgam and resin-based composite restorations treated by sealing of marginal gaps, refurbishment of anatomic form, luster or roughness, and repair of secondary caries lesions, had their longevity increased.