Efficacy of Different Cone-beam Computed Tomographic Protocols in the Identification of Mesiobuccal Canals of Maxillary First Molars: A Tomographic and Ex Vivo Study.

INTRODUCTION: Complementary methods of anatomic diagnosis, including cone-beam computed tomographic (CBCT) imaging, may be useful in the diagnosis of mesiobuccal (MB) canals of maxillary molars. METHODS: Thirty-five maxillary first molars were subjected to ex vivo analysis and 4 CBCT protocols: i-CAT Classic (Imaging Sciences International, Hatfield, PA) (ICC group), i-CAT Next Generation (Imaging Sciences International) (ICN group), PreXion 3D (PreXion, San Mateo, CA) (16.8-second acquisition time; PX1 group), and PreXion 3D (33.5-second acquisition time; PX2 group). The images were evaluated by 2 calibrated endodontists who kept records following protocols previously published in the literature. Micro-computed tomographic imaging was used as the control. RESULTS: The correct identification of anatomic variations of MB roots was 54.3% (n = 19) in the ICC group, 65.7% (n = 23) in the ICN group, and 80.0% (n = 28) in the PX1 and PX2 groups. The probability of agreement between the ICC and the control groups was significantly different from the probability of agreement with the PX1 (P < .05) and PX2 (P < .05) groups. The other groups showed no significant differences compared with the control group. There was no difference in the probability of agreement between the tomographic protocols and the ex vivo results. CONCLUSIONS: The PX1 and PX2 groups were more effective for the diagnosis of MB canals. PX1 is the most suitable because it results in a shorter radiation time and diagnostic imaging similar to PX2. The single-canal anatomy was the most prevalent in the study.