This study aimed to investigate the frequency and type of endodontic procedural errors in cases indicated for retreatment through cone-beam computed tomography (CBCT) analysis.

The sample consisted of 96 CBCT scans, encompassing 122 permanent teeth with fully formed roots. Errors included perforation, instrument fracture, canal transportation, missed canals, and inadequate apical limit of filling. Additionally, potential risk factors were analyzed and subjected to statistical modeling.

The most frequent procedural error observed was the inadequate apical limit of filling, followed by canal transportation, perforation, missed canal, and instrument fracture. Statistically significant associations were identified between various procedural errors and specific factors. These include canal transportation and root canal wall, with the buccal wall being the most commonly affected; missed canal and tooth type, particularly the palatine and second mesiobuccal canal canals; inadequate apical limit of filling and root curvature, showing a higher deviation to the mesial direction in severely curved canals; inadequate apical limit of filling and the presence of calcifications, with underfilling being the most frequent; canal transportation and periapical lesion, notably with deviation to the buccal direction; and the direction of perforation and periapical lesion, most frequently occurring to buccal direction.

CBCT emerges as a valuable tool in identifying procedural errors and associated factors, crucial for their prevention and management.