Morphometric Analysis of the Mental Foramen in Adult Sri Lankan Mandibles

Evidence shows a clear racial variation in the position of the mental foramen. Therefore, detailed knowledge of the morphometry of the mental foramen in different populations is essential in clinical dentistry when administering regional anesthesia, and performing peripheral surgery in the mental region of the mandible. The goal of this study was to elucidate the morphological features and precise anatomical position of the mental foramen with reference to surrounding anatomical landmarks in an adult Sri Lankan population. A total of fifty one adult dry mandibles were assessed to determine the number, shape, orientation, vertical and transverse diameters of the mental foramen and the distance between the mental foramen and symphysis menti. The position of the mental foramen was determined in relation to the mandibular teeth. Data were evaluated between gender and side. The findings indicated that the most common position for the mental foramen was in line with the longitudinal axis of the lower second premolar (52.94%) followed by a position between first and second premolar (26.47%). The mean transverse and vertical diameters of the foramen were 3.31 ± 0.76 and 2.50 ± 0.61 mm, respectively. The mental foramen was located 24.87 ± 6.07 mm (right side) and 24.77 ± 6.07mm (left side) lateral to the symphysis menti. In the majority of cases, the mental foramen was oval in shape (59%) and its usual direction of opening was in a postero-superior direction (49.01%). The incidence of multiple mental foramina was 3.92%. The results of this study provide valuable information that will facilitate effective localization of the neurovascular bundle passing through the mental foramen thus avoiding complications from local anesthetic, surgical and other invasive procedures.