Survival of surgical endodontic treatment performed in a dental teaching hospital: a cohort study

Aim  To assess the survival function of surgical endodontic treatment performed at least 1 year before in a dental teaching hospital. Methodology  A total of 194 teeth surgically treated between 1991 and 2001 were recalled and examined clinically and radiographically using a set of strict criteria. The Kaplan–Meier method and log rank test were used to evaluate the survival time. Confounding factors were examined by Cox regression analysis. Results  The median survival time of the 154 first-time surgically treated teeth was 92.1 months (95% CI: 40.9–143.4) and that of the 40 resurgery cases was 39.1 months (95% CI: 6.1–72.1) up to the date of recall. There was a significant difference in the length of survival between the two groups. For those first-time surgery cases, the preoperative marginal bone loss and the operator had a significant influence on the survival time (P < 0.05). Conclusions  The survival of surgical endodontic treatment declined nonlinearly with time. The preoperative marginal bone loss, operator and resurgery were important factors affecting the survival of this treatment modality.