Abstract
BACKGROUND: This study evaluated the presence of preoperative apical periodontitis (AP) in endodontically treated teeth within a Turkish population, along with its causes, treatment methods, and the effectiveness of preventive and early intervention practices. METHODS: A retrospective analysis was conducted on 1,440 teeth from 1,055 patients treated at Van Yüzüncü Yıl University between 2021 and 2023. Preoperative panoramic and periapical radiographs and postoperative periapical radiographs were examined. Data recorded included patient demographics, treated tooth location, presence of preoperative AP, coronal restorations, reasons for treatment, treatment methods, and number of missing and endodontically treated teeth. Statistical analyses were performed using Chi-Square, Mann-Whitney U, Kruskal-Wallis, and Spearman correlation tests. RESULTS: The overall incidence of AP was reported as 28.7%. It was more frequently observed in the mandible than in the maxilla and in incisors compared to other tooth groups (p < 0.001). Caries was the primary reason for treatment in molars (81.5%), while periodontal disease was more common in incisors (p < 0.001). As age increased, the number of endodontically treated and missing teeth also rose (p = 0.019; p < 0.001). Teeth with crowns had a lower AP rate, while retreatments due to periodontal disease or previous root canal failures showed higher AP rates (p < 0.001). CONCLUSIONS: The high AP rate and the predominance of caries and periodontal disease as treatment causes indicate insufficient application of preventive and early treatments. AP prevalence varied by jaw location, tooth group, coronal restoration and treatment method. This study provides epidemiological data on endodontically treated teeth and their association with AP. These findings emphasize the importance of early diagnosis, preventive measures, and effective treatment planning in preserving tooth survival.