Objectives: CT assessment of the entire course of the inferior alveolar artery (IAA) within the mandibular canal. Methods: After contrast medium injection (180 or 400 mg/ml iodine concentration) into the external carotid arteries of 15 fresh human cadaver heads, the main IAA’s position in the canal (cranial, buccal, lingual or caudal) was assessed in dental CT images of partially edentulous mandibles. Results: The course of the main IAA could be followed at both iodine concentrations. The higher concentration gave the ex- pected better contrast, without creating artefacts, and improved visibility of smaller arteries, such as anastomotic sections, dental branches and the incisive branch. The main IAA changed its position in the canal more often than so far known (mean 4.3 times, SD 1.24, range 2–7), but with a similar bilateral course. A cranial position was most often detected (42 %), followed by lingual (36 %), caudal (16 %) and buccal ( 6 %). Conclusions: With this non-invasive radiologic method, the entire course of the main IAA in the mandibular canal could be followed simultaneously with other bone structures on both sides of human cadaver mandibles. This methodology allows one to amend existing anatomical and histological data, which are important for surgical interventions near the mandibular canal.