Identifying sexual dimorphism in a paediatric South Indian population using stepwise discriminant function analysis

Anthropological research relies on skeletal and dental remains for the identification of species. Sexual dimorphism is the systematic difference in form between males and females of the same species. This study is designed to compute a new formula for sex determination using discriminant function analysis in the deciduous crown dimensions of a paediatric population of South Indian origin and to check its accuracy. The sample consisted of 93 females and 90 males of South Indian origin aged between 5 and 13 years. Alginate impressions of the upper dental arch were made and casts were poured immediately. A digital vernier calliper was used to obtain measurements. Teeth considered for measurement were deciduous maxillary canines and molars. Our study is a maiden attempt in considering diagonal measurements along with mesiodistal (MD) and buccolingual (BL) dimensions as predictor variables for sex determination. Statistical analysis was performed using the Statistical Package for the Social Science version 17.0 software. By using the Student t-test, the different predictor variables of teeth selected between male and females were found to be significant (p < 0.05). Highly significant sexual dimorphism was found in the mean MD dimension of maxillary right canine and right and left first molar, BL dimension of right first molar, distobuccal–mesiolingual of right and left first molar and right second molar and mesiobuccal–distolingual of right second molar. The percentage of sexual dimorphism in MD dimensions revealed that the right upper first molar was the most dimorphic tooth and the upper first molar of the left side was the least dimorphic of the six teeth studied. The present study found the level of sexual dimorphism in the deciduous crown dimensions of a selected group of South Indian population, which is sufficiently large to determine sex with an accuracy of 87.2–88% by discriminant function analysis. Hence the formula derived from the present study could be of some value in sex determination of paediatric populations of South Indian origin.