Background. Knowing the radiologic anatomy of the mandibular canal is essential to perform optimal anesthetic techniques in dentistry, especially in endodontic and surgical procedures. Bifid mandibular canals figure as anatomic variations that may hamper dental anesthesia and lead to surgical accidents.Objective. This study aims to investigate the prevalence of bifid mandibular canals in cone beam computed tomography (CBCT) images of patients under dental treatment.Material and methods. The sample consisted of 700 patients (448 females and 252 males) under dental treatment. CBCT images taken from each patient for dental treatment purposes were analyzed retrospectively in order to search for bifid mandibular canals. The detected bifid mandibular canals were classified according to their morphological arrangement and the prevalence of this anatomic variation was tested for association with patients’ sex using Pearson’s Chi-square test (2).Results. The prevalence rate of bifid mandibular canals reached 2% (n=14). Mandibular canals with an additional bifurcation towards the anterior region of the mandibular ramus were the most prevalent (100%). Lack of statistical association was observed between the occurrence of bifid mandibular canals and patients’ sex ( p >0.05).Conclusion. Despite uncommon, bifid mandibular canals may occur. Dentists must be aware of this anatomic variation to perform safely and optimally in the clinical routine.

O conhecimento do suprimento sanguíneo do seio maxilar, em particular da parede lateral, é de considerável importância devido à possibilidade de rompimento acidental de uma artéria durante os procedimento de elevação do assoalho do seio maxilar. Paciente do sexo feminino, 65 anos de idade, com histórico de complicação pós-operatória, após procedimento de elevação do seio maxilar realizado há três anos. Após avaliação tomográfica, foi observada a presença da artéria antral em posição atípica. Identificar e reconhecer essa estrutura anatômica pelo exame radiográfico pré-operatório, evita possíveis complicações hemorrágicas, durante e após o procedimento cirúrgico.Palavras-chave: Tomografia Computadorizada de Feixe Cônico. Seio Maxilar. Procedimentos Cirúrgicos Operatórios.AbstractIt is very important the knowledge of the maxillary sinus blood supply, in particular of the lateral maxillary wall, due to the possibility of accidental rupture of a vessel during the sinus floor augmentation. A case report is described of a 65-year-old female, who reported a postoperative complication after a sinus augmentation that she had had 3 years before. After radiographic evaluation, it was observed the presence of antral artery in atypical position. The identification of this anatomical structure is very important, by preoperative radiographic examination, avoiding possible bleeding complications, during and after the surgical procedures.keywords: Cone-Beam Computed Tomography. Maxillary Sinus. Surgical Procedures, Operative.