Morphometric study for determining the anteroposterior position of the mental foramen in dentate human subjects

Background: The mental foramen (MnF) is the place where the mental nerve and mental artery exit the body of the mandible, being an important landmark for dentoalveolar surgery. Materials and Methods: For the assessment of MnF topography, we performed a direct morphometric study and two morphometric imaging studies through cone-beam computed tomography (CBCT) scans and orthopantomography (OPG). The following locations of the MnF were investigated: anterior to the first premolar, at the first premolar level, between the two premolars, at the second premolar level, between the second premolar and the 6-year molar, and at the level of the mesial root of the 6-year molar. The data obtained were statistically analyzed by chi-squared test. Results: Through direct morphometry on dentate dry human mandibles, no statistically significant differences were found for the number of MnF located between the two premolars, at the level of the second premolar and between the second premolar and the 6-year molar, depending on age and analyzed side. The number of MnF located between the second premolar and the first molar varies statistically significantly in relation to the subject’s gender but does not vary statistically significantly depending on age and side. By means of imaging morphometry through OPG, we found that the number of MnF located at the first premolar level, between the two premolars, at the second premolar level and between the second premolar and the 6-year molar varies statistically significantly in relation to the age of the patients. Using imaging morphometry trough CBCT scans, we found that the number of MnF located between the two premolars, at the second premolar level and between the second premolar and the 6-year molar varies statistically significantly according to the age of the patients. Comparing the results obtained from the three studies, we found that only according to age the number of MnF located between premolars and at the level of the second premolar varies statistically significantly. Conclusions: Wide and accurate knowledge of both the MnF topography and the key anatomical landmarks used in locating it proves to be essential and clinically relevant in dentoalveolar and endodontic surgery, and for improving anesthesia techniques.