Mandibular Ramus Sexual Dimorphism Using Panoramic Radiography

Abstract

Background: Identification of human remains is the first essential phase of forensic investigation and is significant for subsequent analyses. Mandible is the most dimorphic, largest, and hardest bone of skull and plays a decisive role in sex determination, especially when the complete skull is not available. This study aimed to examine the accuracy of mandibular ramus assessment in sex discrimination using panoramic radiography. Methods: A total of 135 panoramic radiographs (68 males and 67 females; aged 0-75 years) were retrieved from the database of the Department of Oral and Maxillofacial Radiology, Ahvaz Jundishapur University of Medical Sciences, Iran and divided into five groups :4-14, 16-30, 31-45, 45-60, and 61- 75 years. The following four parameters were measured on the radiographs utilizing the mouse-driven method to determine sex: coronoid height (CRH), ramus height (RH), mandibular body height (MBH), and bicondylar breadth (BB). The radiographs were processed using the SCANORA® software. Data were analyzed using receiver operating characteristics (ROC) graphs, t test, and the IBM SPSS software version 22.0 (IBM Corp., Armonk, N.Y., USA). Results: The percentage of certainty of each variable regarding the determination of sex from an unknown human mandible bone was as follows: RH=84.6%, CRH=82.4%, BB=73.5%, and MBH=83.8%, indicating that RH alone could categorize the sex in 84.6% of the cases (highest accuracy), CRH in 82.4%, BB in 73.5% (lowest accuracy), and MBH in 83.8%. The average accuracy in sex determination was 89% using all four variables. Conclusions: All the variables studied in the present study revealed a reliable extent of certainty for sex discrimination of unidentified skeletal remains. The overall accuracy of all variables altogether was 89%.