Diagonal tooth measurements in sex assessment: A study on North Indian population

BACKGROUND: Sexual dimorphism has been of great interest to anthropologists and odontologists. Dental measurements are important in anthropology for the study of sexual dimorphism with most common being the traditional linear odontometric measurements. Apart from these, alternative dental measurements have been developed such as the crown and cervical diagonal diameters and mesiodistal and buccolingual cervical diameters of teeth. AIMS AND OBJECTIVE: The primary objective of the following study is to assess the degree of sexual dimorphism in teeth of a North Indian population using the crown diagonal diameters and secondary is to evaluate the applicability of diagonal measurements in sex determination by means of discriminant functional analysis. MATERIALS AND METHODS: The study sample comprised 200 individuals (100 males and 100 females) of an age group ranging from 18 to 57 years, in a North Indian population. The mesiobuccal-distolingual (MBDL) and distobuccal-mesiolingual (DBML) crown diameters of seven maxillary and seven mandibular teeth on the study models were measured using digital Vernier calipers. RESULTS: The most dimorphic teeth amongst all for crown diagonal diameters are the maxillary central incisors and the least dimorphic are the maxillary second premolars. The mean diagonal crown dimensions in all but one tooth (DBML of maxillary lateral incisor) of males exceeded that of females. The difference was statistically significant in MBDL dimensions of maxillary and mandibular central incisor, canine, first and second molar and DBML dimensions of maxillary central incisor and maxillary and mandibular canine, first molar and second molar (P < 0.05). The accuracy of determination of sex by MBDL crown dimension ranges from 55% to 75% in males and 47-84% in females, while by DBML crown dimension ranges from 55% to 80% in males and 65-80% in females with the overall accuracy of sex determination ranging from 51% to 80% respectively. CONCLUSION: MBDL and DBML crown dimensions are reliable indicators and can be used along with or/and instead of linear measurements in sex determination. In situations in which it is difficult to take correct measurements of linear dimensions of teeth, these alternative odontometric measurements can be used consistently to determine sex.