Anatomical Variations of Mental Foramen and Accessory Mental Foramen

Aim: The mental foramen is a small foramen which is located in the antero-lateral aspect of the body of the mandible. It is situated midway between the upper and the lower border of the mandible and it transmits the mental nerve and the vessels. The knowledge on the anatomy of the mental foramen is very important in clinical dentistry and in surgical procedures which involve that area. Material and Methods: Our study was conducted on 50 adult dry human mandibles from the Department of Anatomy, Isfahan University of Medical Science. irrespective of age and sex. The location, shape, orientation and the presence of the accessory foramen were studied by visual examination. The size and position of the mental foramen were measured by using a digital vernier caliper. Results: Bilateral mental foramina were presented in all 50 mandibles. Accessory mental foramina were found in 6% on left side, 4% on right side and nil bilaterally. Mental foramina were predominantly rounded. The percentages of locations of mental foramina below the apex of second premolar, between first and second premolars and between second premolar and first molar were found as 69.2, 18.1 and 10.4, respectively. Accessory mental foramina were located 0.66 mm lateral to mental foramen and below the apex of first molar tooth. Conclusion: This study may supplement very useful new data of variations in incidence, position, shape and size of mental and accessory mental foramina which may help the surgeons, anaesthetists, neurosurgeons and dentists to help carrying out surgical procedures successfully.