Accessory mental foramina associated with neurovascular bundle in Korean population

To determine the prevalence and anatomical features of accessory mental foramina (AMFs) associated with neurovascular bundle using reformatted CBCT images in Korean population. Three-dimensional, cross-sectional, and axial images of CBCT from total 446 patients were evaluated. To include only AMF associated with neurovascular bundle, the course of accessory nerve through AMF was evaluated on three-dimensional images. The prevalence, locations to mental foramen (MF), and distribution to the adjacent tooth of AMF were analyzed. Additionally, the distance from MF and dimension of AMF were measured. AMFs were found in 36 (8.1 %) patients in the 446 Koreans. The prevalence rate of AMFs in male was significant higher than that in female (p < 0.05). Most AMFs were located anterior-superior to MF. The shortest distance between the center of AMF and that of MF was 5.80 mm (SD +/- A 2.90, 1.40-13.0). Variance of location of AMF in relation to MF was greater in the horizontal direction than in the vertical direction. In related to adjacent tooth, AMF was mainly distributed between the first and second premolars. The horizontal dimension and vertical dimension of AMF were 1.54 mm (SD +/- A 1.41, 0.70-9.80) and 1.44 mm (SD +/- A 0.41, 0.70-2.30), respectively. Knowledge of AMF is important for performing effective nerve block and avoiding injuries to neurovascular bundles passing through AMF. Evaluation of the course of AMF in three-dimensional image of CBCT is effective for confirming AMF associated with inferior alveolar nerve.