EPA Consensus Project Paper: Failure Rates of Direct Versus Indirect Single-Tooth Restorations. A Systematic Review and Meta-Analysis.

Introduction: The purpose of this systematic review and meta-analysis was to evaluate and compare the failure rates of direct and indirect restorations for single-tooth restorations.

Methods: A literature search was conducted by using electronic databases and relevant references for clinical studies on direct and indirect dental restorations with a follow-up of at least 3 years. The risk of bias was assessed with the ROB2 and the ROBINS- I tools. The I2 statistic was used for the assessment of heterogeneity. The authors reported summary estimates of annual failure rates of single-tooth restorations using a random-effects model.

Results: Of 1415 screened articles, 52 (18 RCTs, 30 prospective, 4 retrospective) met the inclusion criteria. No articles with direct comparisons were identified. No significant difference was found in the annual failure rates of single teeth restored with either direct or indirect restorations, which were calculated as 1% using a random-effects model. High heterogeneity was found, ranging from 80% (P⟨0.01) for studies on direct restorations to 91% (P⟨0.01) for studies on indirect restorations. Most of the studies presented some risk of bias.

Conclusions: Annual failure rates were similar for direct and indirect single-tooth restorations. Further randomized clinical trials are needed to draw more definitive conclusions.