Radiographic Healing Outcomes of Apical Periodontitis Following Endodontic Therapy: A Retrospective Longitudinal Study in a Romanian Cohort

Apical periodontitis is a common inflammatory oral condition and a major cause of endodontic treatment need. The present retrospective clinical study aimed to evaluate the frequency, distribution, and radiographic healing of teeth diagnosed with apical periodontitis following primary endodontic treatment or nonsurgical retreatment within a specific patient cohort. Consecutive patients presenting for endodontic treatment at the study clinic between 2020 and 2021 were screened for inclusion. Eligible cases were those in which patients provided written informed consent, presented with periapical inflammatory pathology, and underwent conservative endodontic treatment. Exclusion criteria were incomplete data, non-functional or non-restorable teeth, third molars, pregnancy, probing depth ≥ 4 mm, radiographic bone loss, pathologic tooth mobility due to attachment loss, periodontal involvement of the lesion, and primary dentition. A total of 277 teeth, all diagnosed with apical periodontitis at baseline, were included. Some patients contributed more than one tooth. All treatments were performed by a single operator according to a standardized clinical protocol, including uniform diagnostic criteria, chemo-mechanical preparation, irrigation regimen, obturation technique, and radiographic follow-up at 12 and 24 months. Periapical healing was assessed radiographically using the Periapical Index (PAI). Within this cohort, elderly patients significantly represented the largest proportion of those treated (p < 0.001). Maxillary teeth also comprised a significantly higher proportion of cases than mandibular teeth (55.2% vs. 44.8%). The mean initial PAI score was 3.37 ± 0.9 points, with a median of 3 points, and the final score was 1.31 ± 0.93 points, with a median of 1 point. Radiographic healing was observed in 56.68% of cases at 12 months and in 84.84% of cases at 24 months. Primary endodontic treatment and nonsurgical retreatment of teeth with apical periodontitis in this selected patient population were associated with substantial radiographic improvement over a 24-month follow-up period. These findings support the value of standardized endodontic management and longitudinal radiographic monitoring.