Examining the Prevalence and Location of the Retromolar Canal Using Cone-Beam Computed Tomography Imaging

Background and Purpose: The retromolar canal (RMC) is an anatomical structure in the mandible possibly containing feeding vessels and nerves, which conveys accessory innervation to the mandibular molars or contains aberrant buccal nerves. Damage to this canal can lead to paresthesia and traumatic neuroma. Therefore, it is very important to be aware of the presence of this canal in posterior mandible surgeries. This study aimed to determine the prevalence and location of the RMC in cone-beam computed tomography (CBCT) imaging. Materials and Methods: This study was performed on CBCT stereotypes of 117 patients (74 females and 43 males) in the archives of the Department of Oral and Maxillofacial Radiology (OMFR), School of Dentistry, Ahvaz Jundishapur University of Medical Sciences, who had referred for CBCT scan for various reasons. Radiographs were screened to find the retromolar canal. It was followed by linear measurements (i.e., the horizontal distance from the midpoint of the retromolar foramina (RMF) to the distal of the seventh molar, the diameter of the RMC, and the height of the RMC). Data were analyzed by SPSS software Version 22.0, and the results were tabulated using the t-test and Pearson correlation test. Results: The prevalence of the RMC was 14.5%, equivalent to 17 cases. Linear measurements included the mean horizontal distance from the RMC to the distal of the second molar (15.7±2.5 mm), the mean width of the RMC (2±0.3 mm), and the mean height of the RMC (7.1±1.1 mm). There was no statistically significant association between the prevalence of the RMC and side, gender, and age. Conclusions: Given the importance of this canal, it is recommended to use CBCT before the extraction of wisdom teeth close to the canal.