Mandibular Canal Morphometry and Anatomical Variations Using Cone-Beam Computed Tomography in a North Indian Population: A Retrospective Study

Introduction The present study aimed to evaluate the morphology, dimensions, anatomical variations, and spatial characteristics of the mandibular canal (MC) in a North Indian population using cone-beam computed tomography (CBCT). The associations between MC characteristics and sex, age, and laterality were also assessed to identify clinically relevant patterns of anatomical variation. Materials and methods This retrospective database observational study was conducted using 400 CBCT scans of adults aged ≥18 years between June 2024 and May 2025. The scans were evaluated using multiplanar and curved planar reconstructions. MC course, length, vertical and horizontal diameters, buccolingual position, anterior loop, bifid and trifid canals, and accessory mental foramina were assessed. Two calibrated observers independently evaluated the scans, with repeated assessments performed to establish measurement reliability. Differences according to sex and side, as well as associations with age, were analyzed using generalized estimating equations (GEE) to account for bilateral observations. Multinomial logistic GEE were used for categorical canal patterns. Statistical significance was set at p < 0.05. Results Among the 400 participants, 220 were males and 180 were females, with a mean age of 42.6 ± 12.1 years. Males demonstrated significantly greater canal length, vertical diameter, horizontal diameter, and anterior loop length than females. Bifid canals were significantly more common in males than in females. The ascending canal morphology was the most common pattern, followed by catenary and straight configurations, with no significant sex differences. No significant right-left differences were observed in canal dimensions or anatomical variants. The canal was predominantly centrally positioned buccolingually across all tooth regions, ranging from 67.5% in the second premolar region to 76.0% in the third molar region. Increasing age was significantly associated with reduced canal length, whereas other measured characteristics showed no significant age-related associations. Conclusion MC anatomy demonstrates substantial morphological variability, with significant differences related to sex and age but limited bilateral asymmetry. CBCT assessment provides a detailed characterization of canal dimensions, course, and anatomical variants. Recognition of these variations is important for individualized preoperative evaluation and for minimizing neurovascular complications during mandibular surgical procedures.