Objectives: The aim of the study was to assess the presence, location and the number of accessory or nutrient canals in the body of the mandible by means of cone beam CT images, obtained with the Planmeca ProMax® 3D Max device. Material and methods: Seventy-four cone beam images of the mandible from adult patients (37 males and 37 females) who were imaged for dental implantology planning or third molar extraction were used to assess the number and location of accessory or nutrient canals. All images were taken with the same machine (Planmeca® ProMax 3D Max) at 200-, 400- or 600-μm resolution. Distinction was made between canals entering or exiting the mandible superior or inferior of the inferior alveolar canal and between similar canals superior or inferior of the genial tubercula. Results: The number of accessory canals varied between nil to 11. No statistical significant difference between males and females was found with regard to the number or location of accessory canals in the mandible. Only 5.4 % of patients had no accessory canals. One to five accessory canals were found in 71.6 %, and 23 % of patients had more than five accessory canals. The majority (81 %) of patients had between two and six accessory canals. Conclusion: It seems that subjects showing no accessory canals whatsoever should be considered exceptional as more subjects with than without accessory canals in the body of the mandible were found. Clinical relevance: These results are clinically relevant for mandibular surgery and mandibular local anaesthesia. © 2013 Springer-Verlag Berlin Heidelberg.