Prevalence of Second Mesiobuccal Canals in Maxillary First Molars Detected Using Cone-beam Computed Tomography, Direct Occlusal Access, and Coronal Plane Grinding

The results of this study show that an MB2 canal is present up to 92% of the time. Direct access of teeth found statistically significant more MB2 canals than viewing CBCT volumes alone (P = .032). Therefore, exposing every patient to a preoperative CBCT scan may not be appropriate. However, taking a CBCT scan when an MB2 canal is not found clinically can significantly increase the chances of finding an MB2 canal (P < .001).