THE MANDIBULAR LINGUAL FORAMEN - A CONSISTENT ARTERIAL FORAMEN IN THEMIDDLE OF THE MANDIBLE

The lingual foramen in the midline of the mandible causes confusion in terminology, incidence of occurrence and contents. A survey of 314 dr ied mandibles showed the foramen to be present in 311 specimens (99.04 %). Sectioning of cadaver specimens illustrated a canal traversing the bone to approximately 50% of the buccolingual dimension of the mandib le. The contents of the foramen were found to be an artery, which was an anastomosis of the sublingual branches of the right and left lingua l arteries. Wire markers were placed in the foramen and the genial tub ercles were covered with lead foil to illustrate the radiographic rela tionship between them. The radio-opacity peripheral to the foramen as seen on a radiograph is produced by the wall of the canal and not the genial tubercles as previously reported. While the foramen is not seen on many radiographs of the lower incisor region, this can be accounte d for by a change in orientation of the x-ray beam. A pilot study reve aled an incidence of 49% of the lingual foramen on periapical radiogra phs of the mandibular incisor region in an adult population, the previ ous reported incidence being 28%.