Anatomical Variations of the Mandibular Canal and Mental Foramen in Full Edentulous Iranian Subpopulation: A Cone-Beam Computed Tomographic Study

Background: This study sought to determine the anatomical variations of the mental foramen (MF) and the mandibular canal (MC) in the full edentulous Iranian subpopulation using cone-beam computed tomography (CBCT). These variations can have significant clinical implications in dental implant surgery. Methods: This descriptive cross-sectional study evaluated the mandible CBCT scans of 384 completely edentulous patients that required dental implant treatment. The CBCT scans were retrieved from four radiology clinics in Tehran, Iran, using quota sampling. The reconstructed images were evaluated to determine the dimensions and position of the MC and its cortication at the site of the mandibular first molar, the branching of the MC, the existence of the anterior loop of the mental nerve, and anatomical variations of the MF. The correlations of variables with age and gender were analyzed using the independent t-test, chi-square test, and analysis of variance based on the type of the variable. Results: The cortication of the MC at the site of the mandibular first molar was present in 72.9% of the cases and was significantly more common in male patients (P = 0.0001). Bifid mandibular canal, accessory MF, and anterior loop of mental nerve were present in 9.9%, 65%, and 54.7% of the samples, respectively, and they had no significant correlation with age/gender. The mean MC diameter, the mean MF height, and the mean distance from the inferior border of the mandible to the center of MF were all significantly higher in male patients (P