Chronologic and geographic variability of neurovascular structures in the human mandible.

OBJECTIVES: To compare the dimensions of mandibular anatomical landmarks of human mandibles of three different chronological periods and seven different geographic regions.
METHODS: Cone beam computed tomography (CBCT) images were acquired from human mandibles of three different chronological periods (Neolithic, Medieval and 19-20th Century). The 19-20th Century consisted of seven human mandibular samples from different geographic locations. Image analysis consisted of comparing anatomic variability and dimensions of the mandibular, lingual and incisive canals, mental foramen and their relationship to specific reference teeth as such to determine geographic region and historic period variabilities.
RESULTS: There were statistically significant differences between the 19-20th Century group and the Medieval and Neolithic groups. The 19-20th Century group differed significantly in mandibular canal diameter, tooth root length, length of the lateral lingual canal. In addition, the group also differed from the Medieval sample for the lateral lingual foramen diameter and the midline lingual canal length. Furthermore, the prevalence of anatomic variations was significantly different for the geographic samples tested, with double mental foramina significantly more present in the Congolese sample, and significantly more lateral lingual canals noted in Indonesian and Greenland Eskimo samples.
CONCLUSIONS: This study suggests that mandibular neurovascularisation may show some geographic as well as historic variation. Further studies on larger data samples are needed to verify this statement, as such that it can be potentially used in anthropology and forensic dentistry. More research is also needed to address whether the geographic and historic variations are linked, as well to investigate evolutionary trends in these structures.