Failure of Regenerative Endodontic Procedures: Case Analysis and Subsequent Treatment Options

Regenerative endodontic procedures (REPs) are considered effective treatments for immature necrotic permanent teeth, with favorable outcomes. However, failed cases require subsequent treatment. This study aimed to review and analyze failed cases after REPs and suggest a treatment algorithm to aid clinical decision-making.

A total of 111 REP cases were selected that were conducted between 2015 and 2020. Clinical outcomes were assessed based on clinical and radiographic evaluations. The criteria for failure included persistence of clinical signs or symptoms and/or periapical radiolucency showing persistent apical periodontitis. Cases requiring any treatment intervention, including extraction, were also considered failures.

Sixteen cases were included as failures. The etiology of pulpal disease was stratified into dental trauma (56%), dens evaginatus (25%), and dental caries (12.5%), with the remaining one case having an undocumented cause. The primary reasons for treatment failure were persistent infection (81.3%) and root resorption (18.7%). The identification time of failure varied, with 6 cases (37.5%) detected in less than 6 months and 10 cases (62.5%) later than 6 months after REPs. Sixteen failed cases received 5 different interventions: second REPs, apexification, conventional root canal treatment, surgical approach, and extraction.

Interventions for failed REPs are challenging. Consideration of the treatability of the tooth, accessibility to the canal, and the presence of an apical seat might be key factors in clinical decision-making to obtain a successful outcome.