Repair of Resin Composite Restorations: An Umbrella Review of Systematic Reviews

Objectives: Although the repair of partially defective resin composite restorations is promoted as a minimally invasive alternative to full replacement, existing evidence remains fragmented across systematic reviews with differing scopes and conclusions. This umbrella review synthesized current systematic reviews on the topic, focusing on clinical longevity, adhesive protocols, professional attitudes, and patient acceptance. Methods and Materials: A comprehensive search was conducted in five databases up to April 2025. Eligible systematic reviews assessed clinical or in vitro outcomes, patient or professional perspectives, or decision-making protocols related to resin composite repair. Methodological quality was assessed using AMSTAR 2, and study overlap was evaluated with corrected covered area (CCA). Findings were interpreted across five thematic domains using the PROPS framework (Patient-centeredness, Risk of bias, Outcomes, Protocols, Significance). Results: Seven systematic reviews were included. A meta-analysis found no significant difference in failure rates between repaired and replaced restorations (RR= 1.21; 95% CI: 0.51-2.83), though evidence certainty was low. A network meta-analysis of laboratory studies identified that diamond bur + silane + adhesive yielded the highest bond strength (mean: 24.5 MPa). Surveys reported high patient acceptance (> 86%) and professional endorsement of repair, yet only 31.3% of defective restorations were repaired. Standardized decision-making tools were lacking. Conclusions: Repair is a clinically sound, conservative option that can offer outcomes comparable to full replacement when appropriately indicated and proper protocols are used. Broader implementation requires guideline standardization, clinical training, and studies incorporating patient-reported outcomes and cost-effectiveness.