Accessory mandibular foramen during dental implant placement: case report and review of literature

Accurate knowledge of vital anatomical structures, such as the inferior alveolar nerve, mental nerve, and mental foramen, is critical to achieve favorable results during oral surgical procedures and dental implant placement. Although uncommon, variations in mandibular foramina have been reported and if unnoticed and, as a result, injured, may lead to patient morbidity, neurosensory disturbances, and other undesired complications. We present a case report of identification of an accessory mandibular foramen (AMF) encountered during placement of 2 dental implants for a mandibular implant-retained overdenture and demonstrate appropriate management. In addition, we propose a more reasonable terminology for such accessory foramina so as to facilitate communication through common terminology among health care providers. As conventional radiography (periapical and panoramic films) may not allow for proper identification of such anatomical variations, cone-beam computed tomography may be useful in the diagnosis of AMF during treatment planning of dental implants in the mandible.