A tubular channel or passage. The pulp canal is that part of the root of a tooth which contains the pulp tissue; it is bounded by dentine. An accessory root canal is a lateral branch of the main root canal usually occurring in the apical third of the tooth root. The mandibular (inferior dental) canal extends from the mandibular foramen on the medial surface of the ramus of the mandible to the mental foramen and contains the mandibular artery and vein and the mandibular branch of the trigeminal nerve. Nutrient canals through which blood vessels pass are present in the alveolar bone of the mandible and maxilla.