Evaluating Outcomes and Prognostic Factors in Endodontic Microsurgery: A Retrospective Cohort Study.

[INTRODUCTION] Outcome studies are essential for evidence-based endodontics. This study evaluates rates of radiographic periapical healing and survival to reintervention in endodontic microsurgery (EMS), along with the prognostic factors associated with these outcomes.

[METHODS] Dental records were reviewed to identify teeth treated with EMS at the University of Toronto between 1999 and 2021. Each tooth was tracked until the final follow-up (minimum of 1 year) or an untoward event. Radiographic periapical healing, survival, and their prognostic factors were analyzed using logistic and Cox regression, respectively. Median (interquartile range [IQR]), odds ratios (ORs), hazard ratios (HRs), and 95% confidence intervals (CIs) were calculated (P < .05).

[RESULTS] A total of 128 teeth met the criteria for radiographic periapical healing analysis, and 186 teeth were included in the survival analysis. The median follow-up time for radiographic periapical healing was 41.5 months (IQR: 27.8-72.9). At the latest follow-up, the overall radiographic periapical healing rate was 82.8%, and it was significantly associated with the absence of periodontal involvement (OR: 2.8, 95% CI: 1.1-7.7, P = .045) and root-end filling depth >2 mm (OR: 3.5, 95% CI: 1.2-9.6, P = .014). Median survival follow-up time was 37.5 months (IQR: 22.3-61.6); 86.6% of teeth survived without reintervention, 1.6% required treatment, and 11.8% were extracted. Age ≤45 (HR: 3.0, P = .036) and root-end filling ≤2 mm (HR: 4.3, P = .004) increased the risk of intervention.

[CONCLUSIONS] Both radiographic periapical healing and survival rates following EMS are high. Prognostic factors were identified, which require confirmation in future studies.