Permanent Maxillary Odontometrics for Sex Estimation Based on a 3-Dimensional Digital Method

BACKGROUND: In the field of forensic medicine, sex estimation is a critical step in personal identification. Teeth are the hardest tissue and have high temperature resistance and corrosion resistance. In cases such as an airplane crash or the corpse of an unknown person, teeth often play a crucial role in identification. This study applied 3-dimensional technology to obtain odontometrics of permanent maxillary teeth and to examine the sexual dimorphism, finding suitable discriminant indicators to construct appropriate equations for sex estimation. MATERIAL/METHODS: A total of 204 participants (104 men and 100 women) from the Han population in Kashgar were included. Plaster models of their maxillary dentition were obtained to scan and measure through an accepted and commonly used 3-dimensional digital method. Descriptive statistics, t tests, and discriminant analyses were statistically analyzed using IBM SPSS 23.0 software. RESULTS: This study showed high intra- and interexaminer reliability (intraclass correlation coefficient >0.950). There were statistically significant sex-related differences (P<0.05), with male values generally being higher for buccolingual distance, mesiodistal distance, intercanine distance, crown area, crown module, crown index, and maxillary canine index. Compared with other measurements, mesiodistal distance and crown area indicator exhibited distinct sexual dimorphism. In addition, several appropriate equations were constructed through different discriminant analyses that could be used to estimate sex in our specific population. CONCLUSIONS: Three-dimensional digital technology offers a promising method for odontometry. Combining mesiodistal distance and buccolingual distance of particular teeth or using maxillary canine index in discriminant functions are acceptable auxiliary tools for sex estimation in the forensic field.