OBJECTIVE The mandibular canal must be considered in dental procedures to avoid injuries of the alveolar inferior nerve. The occurrence of anatomical variations of the mandibular canal increases the risk of neurovascular injuries. The purpose of this study was to identify and describe the prevalence of mandibular canal branching (MCB) using cone beam computer tomography (CBCT). METHODS Seven hundred standardized CBCTs were selected. The images were evaluated for the presence of MCB and for the detection of pathologies that could affect the structure of the canals. The data were analyzed using descriptive statistics and the Chi-squared test. RESULTS The prevalence of MCB was 41.1%. There was no statistical difference between genders with the presence of the branches (p > 0.005). The highest prevalence was in the premolar and retromolar regions. Pathologies found in the molar region were frequently connected with MCB (77.8%), and the most common pathology related to branches was periapical lesion. CONCLUSIONS Mandibular canal branching presented a high prevalence in CBCT imagery, more frequently located in regions of the premolar and retromolar. An adequate diagnosis of the MCB is necessary to perform dental procedures and verify possible associated pathologies.