The feasibility of using computerized tomography images of mandibular ramus, frontal sinus, and craniofacial morphometric measurements for age and sex determination in gaziantep province

III. ABSTRACT THE FEASIBILITY OF USING COMPUTERIZED TOMOGRAPHY IMAGES OF MANDIBULAR RAMUS, FRONTAL SINUS, AND CRANIOFACIAL MORPHOMETRIC MEASUREMENTS FOR AGE AND SEX DETERMINATION IN GAZIANTEP PROVINCE Emine DURSUN KALKAN Specialization Thesis in Medicine, Department of Forensic Medicine Advisor, Prof. Dr. Aysun BARANSEL ISIR February-2023, 103 pages Introduction and Aim: Sex and age determination is an essential step in forensic identification, especially in the case of severely decomposed corpses and large numbers of fatality cases. For sex determination from skeletal remains, the skull and pelvic bones are used. These have been studied many times before and have proven to be reliable. Metric or morphologic methods are used in the examination of bones. The use of radiologic methods such as CT for metric measurements has increased in recent years. CT scans are archival and offer the advantages of reproducibility and accessibility to multiple observers and reduced time and cost for analysis. This study aims to evaluate and compare the measurements of some craniofacial points, frontal sinus and mandibular ramus, which are frequently used in identification, and to investigate the usability of these measurements individually and together for age and sex estimation. Materials and Methods: 100 females and 100 males are divided into two groups. The groups are divided again into five subgroups based on age 20-29, 30-39, 40-49, 50-59, and 60-75. Seven metric measurements in the cranium, three metric measurements in the frontal sinus, and one length measurement in the ramus of the mandible are made by using brain CT and CT angiography images. These images are obtained randomly and retrospectively in Gaziantep University Sahinbey Research and Application Hospital, Department of Radiodiognastics. The measurements are analyzed in SPSS 22.0. Numerical variables are compared according to sex and age groups. To estimate sex, the Quadratic Discriminant Analysis method is used, different models are constructed and compared, and the most important models for estimating sex parameters are determined. Findings: The measurements of mandibular ramus length, frontal sinus and craniofacial parameters evaluated in this study are higher in males than females, and all measurements show sexual dimorphism. None of the measurements successfully separated the age groups between 20 and 75 except for the interorbital width. The interorbital measurement is able to distinguish between individuals aged 60 and over and individuals aged 20-29, 30-39, and 40-49. The most valuable variables for sex determination are the bizygomatic width among the cranial metric measurements and the antero-posterior diameter of the frontal sinus among the frontal sinus measurements. It is determined that the seven cranial parameters can discriminate sex with 86% accuracy, mandibular ramus length alone with 75% accuracy, frontal sinus height, width and antero-posterior diameter with 73.5% accuracy. When all these measurements are used together, the success of discriminating sex reaches 89%. In addition, the mandibular ramus length is between 6-6.9 cm in 57% of individuals over 20. Result: The findings of this study support that mandibular ramus, frontal sinus and craniofacial morphometric measurements made with the CT technique can be used for sex determination with high accuracy rates. By applying these cranial measurements to the discriminant formulas created in this study, sex can be estimated with high reliability. However, the same method does not have significant discriminant power for age determination. This study provides findings specific to the Turkish population that can be useful for criminal investigations and identifying victims in mass disasters. Keywords: skeletal age determination, skeletal sex determination, frontal sinus, craniometric parameters, mandibular ramus length, forensic medicine, radiology