Failure case analysis during each stage of endodontic microsurgery: A retrospective study based on clinical databases

Introduction: This study aimed to investigate the most important stage of endodontic surgery by examining failed cases and analyzing the cause of failure during each stage of the procedure. Materials and Methods: We searched the clinical database of the Department of Conservative Dentistry, Dankook University, for patients with a history of endodontic microsurgery (EMS) performed between March 2017 and February 2021. Among the 428 patients who underwent EMS, those with a history of endodontic surgery were included. All surgical procedures were performed using a microscope, and the previously resected root surface or the root surface to be resected was inspected during surgery. The patients were followed up at 6 and 12 months and every year thereafter. Results: A total of 68 cases were included for analysis. The most common cause of failure was incomplete root-end filling (24 cases, 35.3%), and mineral trioxide aggregate (MTA) was used in 17 cases. This was followed by no root-end management after root-end resection (33.8%), incorrect root-end preparation (19.1%), inspection error (7.4%), cracks (2.9%), and incomplete root-end resection (1.5%). After resurgery, 41 were followed up for more than 1 year (recall rate, 60.3%), and the success rate was 85.4% (35 out of 41 cases). Conclusions: Root-end filling was shown to be the most important stage in determining the outcome, even when using the biocompatible material, MTA.