Location of the infraorbital and mental foramen with reference to the soft-tissue landmarks

The purpose of the present study was to determine the locations of the infraorbital foramen and mental foramen based on soft-tissue landmarks to facilitate prediction of the locations of these structures during facial surgery.

Fifty embalmed cadavers (100 sides) of Koreans were dissected to expose the infraorbital foramen and mental foramen. The distances between the bilateral infraorbital foramina and between the mental foramina and the distances between the alae of the nose and between the corners of the mouth (cheilions) were measured directly on the cadavers, and the vertical and horizontal distances between the infraorbital foramen and mental foramen and the ala of the nose and cheilions, respectively, were measured indirectly on photographs.

The distance between the bilateral infraorbital foramina (54.9 +/- 3.4 mm) was greater than that between the bilateral mental foramina (47.2 +/- 5.5 mm). The infraorbital foramen was located 1.6 +/- 2.7 mm lateral and 14.1 +/- 2.8 mm superior to the ala of the nose. The distance between the ala of the nose and the infraorbital foramen was 15.9 +/- 2.8 mm, and the horizontal angle between these structures was 64.1 +/- 9.9 degrees laterosuperiorly. The mental foramen was located 20.4 +/- 3.9 mm inferior and 3.3 +/- 2.9 mm medial to the cheilions. The distance between the cheilions and mental foramen was 20.9 +/- 3.8 mm, and the vertical angle between these structures was 9.2 +/- 8.1 degrees inferomedially.

This study provides data that will be useful in predicting the locations of the infraorbital foramen and mental foramen when used together with hard-tissue landmarks. These data may be particularly helpful for facial surgery in patients with missing teeth.