AbstractIntroduction: Identification of a deceased person is of utmost importance from social and medicolegal viewpoint. Skull is the second most preferred bone after pelvis for identification of sex of the deceased as it is highly dimorphic and craniometry is highly objective and reproducible. Craniometric indices show the relationship between different dimensions and are crucial for classification of race and sex ofunknown skeletons. Several studies have been conducted on various craniometric indices. Upper facial index is the percentage ratio of upper facial height to facial width. Recently it has been proposed as a novel index for sexual dimorphism but its status as a sexually dimorphic trait has not yet been well established and is questioned by a few studies. Hence to evaluate the sexual dimorphism of upper facial index and to provide population specific data on facial morphometry, this study was performed on adult Indian skulls. Methods The study was performed on 100 adult Indian skulls (60 male and 40 female) of known age and sex. Parameters measured were upper facial height and bizygomatic breadth using sliding and spreading calliper. Upper facial index was calculated. These parameters were expressed in descriptive statistics i.e. mean, range and standard deviation and the difference of their means between male and female skulls was compared for significance using the Student t-test. Results were compared with available literature Results In the present study, mean upper facial height (nasion-prosthion height) in male and female skulls was 61.71±3.65mm and 56.49±3.15mm respectively while bizygomatic breadth (maximum bizygomatic diameter) was 127.63±4.79mm and 121.33±4.28mm respectively. Student’s t test shows the difference of their means between male and female skulls to be statistically highly significant. The mean upper facial index was 48.36±2.52 in male, while it was 46.60±2.72 in female skulls placing most of the skulls in euryene (broad face) category with a few female skulls in hypereuryene (very broad face) and a few male skulls in mesene (round face) category. The difference of means of upper facial index between male and female skulls was also statistically significant. Conclusion: This study ascertains that the upper facial height, bizygomatic breadth and upper facial index are statistically significant sexually dimorphic traits which can be used for sexual dimorphism of adult Indian skulls. The facial morphometric data provided by this study will be helpful in anthropology and forensic medicine for evaluation of race and sex as well as in facial reconstruction surgeries, evaluation of facial trauma and congenital anomalies.
Keywords: Upper facial height; Nasion-prosthion height; Bizygomatic breadth; Upper facial index; Sexual dimorphism; Skull.