Sex estimation from the mandible in 3D computed tomography images

This study aimed to reveal sex-related variable characteristics through morphometric measurements on the mandible and to predict sex in individuals from different age groups using these variables.

This study was conducted on mandible images obtained through 3D reconstruction (using RadiAnt DICOM viewer) of head and neck computed tomography (CT) scans of 152 individuals (77 males, 75 females) aged between 20 and 98 years. Morphometric measurements were performed for each mandible concerning the foramen mentale, condylus mandibulae, incisura mandibulae, and angulus mandibulae. In addition to these, the bigonial distance was also measured. All measurements except for angulus mandibulae were conducted using RadiAnt DICOM Viewer 2020.1.1. The data were analysed using SPSS 20.0 for Windows.

When parameters were compared by sex, the means of all measurements, except for the left angulus mandibulae, were higher in males than in females. Statistically significant differences between sexes were found in the distances from the condylus mandibulae to the gonion on both sides. The highest dimorphism rate was observed in the incisura mandibulae (right: 14.39%, left: 14.29%), while the lowest was found in the angulus mandibulae (right: 0.12%, left: 0.57%). The logistic regression model correctly classified 91.4% of individuals in the development sample, whereas discriminant analysis yielded 90.1% original and 85.5% leave-one-out cross-validated accuracy.

Our findings indicate that sex estimation can be successfully performed using external measurements of the mandible. According to our findings, important parameters that can be used for sex differentiation, such as the bigonial distance measurement and the gonion-mandibular condyle measurements, are present on the mandible. Our method may be valuable in the fields of anatomy, forensic medicine, and anthropology, particularly for sex estimation studies.