A comparative anthropometric study of the position of the mental foramen in three populations

The position of the mental foramen was recorded in relation to the mandibular teeth and anatomical landmarks on the mandible in 76 Chinese, 46 European and 33 Indian skulls of known or calculated age at death. One way analysis of variance (ANOVA) with Tukey's test was used to compare the means of the three groups.

The length of Indian mandibles was significantly smaller than that of Chinese (p <0.001) and European (p <0.05), but there was no significant difference between European and Chinese mandibles (p >0.05). The distance from the symphysis menti to the mental foramen was not significant in European and Indian mandibles (p >0.05), though the latter were significantly smaller than the Chinese (p <0.001). The distance from the mental foramen to the posterior border of the ramus of the mandible was significantly larger in Chinese and European skulls compared to that of Indian (p <0.01), there being no significant difference between European and Chinese (p >0.05). There was no significant difference in the relative position of the mental foramen (distance from symphysis menti to the mental foramen divided by the length of the mandible) between the Chinese and Indian mandibles (p >0.05) but there was a significant smaller difference between the European and both Chinese and Indian (p <0.001). The modal position of the foramen in the Chinese was in line with the long axis of the second premolar, while the European and Indian between the first and second premolar.

The notion that the mental foramen lies between the first and second premolars can no longer be accepted. Population differences occur and preoperative radiographs are mandatory.