Position and course of the mandibular canal in skulls

Objective. The aim of this study was to examine and describe the topography of the mandibular canal (MC) in both vertical and occlusal dimensions. Study Design. Fifty-two adult skulls deposited in the University of Pittsburgh School of Dental Medicine skull collection were evaluated in this study. Cone-beam computerized tomographic scans of each skull were obtained. Results. The vertical course of MC was classified into 3 types: straight projection (12.2%), catenary-like configuration (51.1%), and progressive descent from posterior to anterior (36.7%). The evaluation of the buccolingual dimension showed that the mandibular canal was located either in contact with or close to the lingual cortical plate (<= 2 mm) in the molar region of the majority of the cases. As it proceeds anteriorly it moves toward the buccal aspect of the mandible, where it finally emerges through the mental foramen. Three emerging patterns of mandibular canal were observed: sharp turn (53.2%), soft curved exit (28.8%), and straight path (17.4%). The examination of the vertical dimension showed that the canal was located almost 1 cm above the inferior border of the mandible and then ascended to reach the mental foramen, which is located similar to 16 mm (range 13.4-20.3 mm) above the inferior border of the mandible. We found a strong correlation between height of the mandible and location of the mental foramen (r = 0.64; P < .0001). Conclusions. The course of mandibular canal described in vertical and axial dimensions and variation in its path have been classified. In addition to variation in location of MC, it has different anatomic configurations which clinicians should be familiar with in any surgical procedures involving the posterior mandible. (Oral Surg Oral Med Oral Pathol Oral Radiol 2012;113:453-458)