Rugae patterns as an adjunct to sex differentiation in forensic identification

It is widely acknowledged that in some forensic situations there are limitations to identification of the deceased by fingerprints, DNA and dental records. Palatal rugae pattern of an individual may be considered as a useful adjunct for sex determination for identification purposes. The aim of this study was to identify and compare the rugae pattern in Indian males and females, as an additional method of differentiating the sexes in various postmortem scenarios. Dental stone casts of 120 Indians: 60 males and 60 females were obtained. The method of identification of rugae patterns was that of Thomas and Kotze (1983) and Kapali et al (1997) which includes the number, length, shape and unification of rugae. Our study revealed no significant difference in the total number or various length measurements of rugae between the two sexes which conforms to previous results. However, in terms of the different types of rugae shape, the converging type of rugae were statistically greater in number in females whilst the circular type of rugae were statistically greater in number in males, which contrasts with earlier studies. The use of logistic regression analysis (LRA) enabled highly accurate sex prediction (>99%) when all the rugae shapes were analyzed. It may be concluded that rugae pattern through the use of LRA can be an additional method of differentiation between the Indian male and female and assist with the identification process in conjunction with other methods such as visual, fingerprints and dental characteristics in forensic sciences.