How protocol, posts, and experience affect fracture detection in multi-rooted teeth using cone-beam computed tomography: an ex vivo experimental study.

Objectives: This study aimed to evaluate the influence of cone-beam computed tomography (CBCT) acquisition protocol, the presence of intraradicular metal post, and examiner experience on the detection of complete root fractures in multi-rooted teeth. Methods: Twenty human molar teeth filled with gutta-percha were placed into artificial alveoli created in bovine ribs. The sample was divided into two groups based on the presence or absence of intraradicular posts in the distal roots. CBCT scans were obtained using four acquisition protocols with varying voxel sizes (0.28, 0.2, 0.125, and 0.80 mm). Following the creation of controlled fractures using a chisel and hammer, CBCT imaging was repeated, resulting in 160 images. Five examiners assessed the images using OnDemand software (KaVo Dental GmbH). Sensitivity, specificity, and accuracy were calculated for each examiner, CBCT protocol, and post-condition. Statistical comparisons were performed using Cochran's Q test and McNemar test, and a significance level of 5%. Results: In teeth without metallic posts, sensitivity, specificity, and accuracy values exceeded 0.70, 0.70, and 0.80, respectively. However, the presence of metallic posts significantly reduced diagnostic performance, particularly in low-resolution protocols evaluated by less-experienced examiners. Conclusions: CBCT acquisition protocols should be selected based on the presence of metallic posts to optimize root fracture detection in multi-rooted teeth. Examiner experience also plays a critical role in diagnostic accuracy.