NON METRIC DENTAL CROWN TRAITS IN A DISTINCT TRIBE OF SOUTH INDIA

Background: Non-metric dental crown traits (NDCT) are an established ancillary means of race identification.
Population specific NDCT need to be identified in ethnic groups as these may serve as adjuvant tools in population
and individual identification. Scanty studies are found on the tribal population of India and on tribals of Kerala. Irula
Tribals constitute a distinct ethnic population of Palakkad district in the state of Kerala, South India. The present crosssectional descriptive study was done on 150 males and 150 females of this population to assess the frequency,
distribution and sexual dimorphism of NDCT as an adjunct in population identification.
Materials and Methods: Intraoral maxillary and mandibular impressions were taken and casts were prepared.
Twenty- six maxillary and thirteen mandibular NDCT were examined and recorded. The grade-wise frequency and
variability of these traits were analysed using Chi-squared test with SPSS Version 25 (p-value < 0.05).
Results: High incidence of shovelling (72% of males and 62% of females) and cusp of Carabelli (44% in males and
39.3% in females) was observed. Grading for shovelling was between 1 and 3 in 59.4% of the population, and that for
cusp of Carabelli was only 1 in 16%. Labial convexity showed low incidence as well as low grading. Sexual
dimorphism was observed in six traits, of which three had fairly high incidence.
Conclusion: Shovelling and cusp of Carabelli may define the Irula population due to higher incidence and strong
manifestation, while it may not be possible to consider labial convexity as a trait for this population. The studied
population shows an affinity to Europeans based on the incidence of traits exhibiting distinct geographic variation.
Further studies are recommended on non-metric traits in Irula as well as other tribal populations of India.