IJAR.2025.294
Type of Article: Original Research
Volume 14; Issue 1 (March 2026)
Page No.: 9456-9460
DOI: https://dx.doi.org/10.16965/ijar.2025.294
Sex Determination by Applying Discriminant Functional Analysis on Mandibular Morphometry: A Cross-Sectional Study of Gujarat’s Population
Urvi H. Dave 1, Rajesh B. Astik *2.
1 Assistant Professor, Department of Anatomy, Ananya College of Medicine and Research, Kalol, Gujarat. 382721, India. ORCiD: 0009-0006-2613-8536
*2 Professor, Department of Anatomy, GMERS Medical College, Himmatnagar, Gujarat. 383001, India. ORCiD: 0009-0008-7450-2093
Corresponding Author: Dr. Rajesh B. Astik, Professor, Department of Anatomy, GMERS Medical College, Near Government Polytechnic College, Gadhoda Road, Himmatnagar, Gujarat. 383001. India. E-Mail: astikrajesh@yahoo.co.in
ABSTRACT
Background: The mandible is the strongest bone of the skull, and it is commonly utilized in forensic anthropology for determination of sex from skeletal remains. It has been extensively studied by both metric and non-metric methods, but for this purpose an intact mandible is often required.
Aim and objective: The present study was aimed at to investigate the sex-discriminating potential of the metric data from the mandible in the people of the Gujarat, and to develop a discriminant function scores for sex determination using mandibular parameters. The objectives of the study were to measure and compare various mandibular parameters viz. bi-gonion diameter (Bi-go), minimum ramus breadth (MnRB) and maximum ramus height (MxRH) between males and females in the Gujarati population to evaluate the significance of these parameters in determining sex; to develop discriminant function scores that can accurately classify mandibles as male or females based on these parameters; and to assess the accuracy of the discriminant function scores in determining sex from unknown mandibles.
Results: A total of 400 dry and adult mandibles with intact alveolar margin of unknown sex obtained from the Department of Anatomy of Medical Colleges of Gujarat, were studied. Mean values for all the three parameters; bi-gonion diameter, minimum ramus breadth (MnRB) and maximum ramus height (MxRH) were greater for males than for females, and difference in means calculated using student’s t test was significant at p-value less than 0.01. The accuracy of discriminant function MnRB in correctly sexing mandible was 80.97% for males, 81.98% for females and 94.50% overall and MxRH in correctly sexing mandible was 81.45% for males, 87.90% for females and 94.75% overall. The same for bi-go in correctly sexing mandible was 82.57% for males, 85.53% for females and 91.58% overall.
Conclusion: The discriminant function scores analysis proved to be a useful diagnostic tool in the field of forensic anthropology and provide a valuable tool for sexual dimorphism.
Key words: Dry mandibles, Mandibular ramus, bi- gonion diameter, Discriminant functional analysis, Sex determination by skeleton.
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