Critical analysis of anatomy and classification of retromolar canal: an observational CBCT study

The retromolar canal (RMC) is an anatomical structure of the mandibular bone located distal to the last molar. The frequency of anatomical variation in human anatomy is approximately 30-35%. This study aimed to evaluate the prevalence of the retromolar canal in a population subjected to cone beam computed tomography (CBCT).

The radiographic images belonged to 200 patients (100 males and 100 females; older than 13 years old) were examined following a strict protocol. Four hundred hemi-mandibles of 100 male and 100 female patients were examined between 2019 and 2022.

The collected data showed 136 patients presented the RMC, bilateral in 72 cases (68%) and unilateral in the other 64 cases (32%). Gender variation did not yield statistically significant differences, with 76 male (56%) and 60 female (44%) patients affected (P>0.05). A statistically significant difference was observed for side predilection, with unilateral RMC more prevalent on the right side in 24 cases (37.5%) and on the left side in 40 cases (62.5%) (P<0.05).

Based on the results obtained and other anatomical considerations, this study proposes a new classification for RMC.