Evaluation of the Course of Inferior Alveolar Canal and its Relation to Anatomical Factors on Digital Panoramic Radiographs

STATEMENT OF THE PROBLEM: The inferior alveolar canal (IAC) is a bony canal that starts from mandibular foramen at the inner surface of the mandibular ramus and extends along the ramus and body of mandibular bone in forward and downward directions to the mental foramen. Inside the mandibular canal, there are lower alveolar artery and a nerve with the same name. Understanding the anatomical details of the lower alveolar canal, including position, pathway and morphology to prevent complications in surgical procedures in the lower jaw such as mandibular impacted molar surgeries, mandibular nerve block injection, or even root canal treatment of mandibular teeth is important. PURPOSE: The purpose of this study was to investigate the course and direction of IAC in mandibular bone and its relation to anatomical factors such as gonial angle and location of entrance of IAC in the mandibular ramus. MATERIALS AND METHOD: This cross-sectional study evaluated a sample of 280 digital panoramic images. All samples were Iranian. The pattern and direction of the IACs were recorded according to age and gender and the relation of these patterns to the gonial angle of mandible and the entry point of the IAC in mandibular ramus were evaluated. RESULTS: The results showed that the course of canal, the entrance point of the canal and the gonial angle were the same between different age groups and between two genders. There was no significant relation between the course of canal and the two anatomical variables mentioned (p> 0.05). CONCLUSION: Considering the increasing frequency of implant surgeries and presence of different courses of the mandibular canal and concerning the important complications such as paresthesia caused by damage to the mandibular nerve, panoramic radiography is necessary before any surgery in this area to avoid unwanted injuries to the neurovascular system if other advanced modalities are not available.