Palatal rugae patterning in a modern Indonesian population

Background: Palatal rugae patterning has been suggested as useful complementary information for forensic purposes, when there are limitations in using the primary identifiers and when the individual patterning from e.g. a dental cast can be traced or the pattern can differentiate between alternative populations of origin. Objectives: The aim of this study was to identify the rugae patterns in a sample modern Indonesian population, to compare the patterns to previously reported observations, and to consider the requirements for possible forensic applications. Material and methods: Archival dental casts were randomly selected to include 47 male and 53 female Indonesian patients of the Dental Hospital of the Faculty of Dentistry, University of Indonesia. The age and ethnic/geographic origin of the subjects were also recorded. The Trobo classification was applied to analyze the rugae shape patterns. Results: The results showed the line, sinuous, and curve types of rugae as predominant shapes, representing together about 83 % of the rugae of the study sample that for its size was considered reasonably representative of the Indonesian population. All recorded individual rugae patterns were unique, i.e. no similar patterns were found for any two individuals. The results are consistent with slow rugae loss at an average rate of one ruga in about 15 (±2) years after early adulthood. Conclusions: The palatal rugae patterns provide potentially useful supplementary information to establish the identity of an individual, but only when appropriate antemortem data are available. For this purpose, it is suggested that optical 3D oral/dental scanning is used to retain the data on the rugal and oropalatal patterns. Suitable pattern recognition methods may also reduce the potential effects of rugae modification in time.