Prevalence of middle mesial canal in mandibular molars: A cross-sectional cone-beam computed tomography study.

Background: The first tooth to erupt is the first mandibular molar, which is the tooth with the highest number of retreatments. Several factors are responsible for the failure of the endodontic success and one of the most important being the particular pulp anatomy of each tooth. To aim was determine the prevalence of the middle mesial (MM) canal in first mandibular molars and to study if there are predisposing factors to the presence of this canal by retrospectively analyzing cone-beam computed tomography (CBCT) images in vivo.