Evaluation of lingual vascular canals of the mandible with Computed Tomography.

Purpose: To assess the anatomy of the mandibular lingual vascular canals with the use of computed tomography (CT).
Materials and Methods: Seventy consecutive patients underwent preimplantation CT of the mandible. CT images were obtained on axial plane by using a bone reconstruction algorithm and then processed with dedicated software (Dentascan). The number of lingual vascular canals, the diameter of their entrance foramina and the distance of the foramina from the symphysis menti and from the lower edge of the mandible were measured in each patient. The median superior canal (MSC), the median inferior canal (MIC), the lateral mesial canals (LMC) and the lateral distal canals (LDC) were evaluated separately.
Results: 0 to 5 canals were found in each patient. The MSC was found to be present in 98.6% of cases; the mean diameter of the entrance foramen was 0.85+/-0.28 mm located adjacent the symphysis menti and 11.3+/-2.6 mm from the inferior margin of the mandible. The MIC was found to be present in 32.9% of cases; the mean diameter of the entrance foramen was 0.58+/-0.21 mm located adjacent the symphysis menti and 5.5+/-2.2 mm from the inferior margin of the mandible. LMCs were found to be present in 38.6% of cases; the mean diameter of their entrance foramina was 0.60+/-0.24 mm located 5.1+/-2.5 mm from the symphysis menti and 6.3+/-3.2 mm from the inferior margin of the mandible. LDCs were found to be present in 48.6% of the patients; the mean diameter of their entrance foramina was 0.58+/-0.19 mm located 19.3+/-7.3 mm from the symphysis menti and 6.6+/-5.4 mm from the inferior margin of mandible.
Conclusions: Dental CT detects the lingual vascular canals of the mandible in a high percentage of subjects and allows a good demonstration of their number, location and entrance foramen diameter. The evaluation of these canals is important in the preoperative planning of dental implants or in the planning of dental surgery in general so as to avoid bleeding due to damage of the vessels present in these canals.