Course and Topographic Relationships of Mandibular Canal: A Cone Beam Computed Tomography Study

Objectives: The purpose of the present study was to determine the location and configuration of the mandibular canal and related vital structures as a pre-implant assessment using Cone Beam Computed Tomography. Materials and Methods: 141CBCT scans were undertaken by Kodak 9500® Cone Beam 3D Systems and the scanning parameters were 90 kV, 10 mA, voxel size 0.2 mm and medium field of view. Results: The course of the mandibular canal reported (61.17%) catenary-like, (28.19%) progressive descent and (10.64%) had a straight pattern. The buccolingual dimension showed that the mandibular canal was located close to the lingual cortical plate (almost 2-3 mm) in the molar region and as it proceeds anteriorly it moves toward the buccal aspect of the mandible to emerge finally through the mental foramen. 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 15.72mm (range 13.82-18.25 mm) above the inferior border of the mandible. Conclusions: Anatomic variations and lesions affecting the mandibular canal were common findings in the CBCT images of the mandible produced for dental implant planning. An awareness of these alterations is important for dentistry because some of them might require treatment, change oral surgery planning and difficult inferior alveolar nerve anesthetic block.