The cusp of Carabelli: Frequency, distribution and type in the Bengaluru population

Detailed description and study of teeth traits could provide valuable information regarding phylogeny of man and distinctions between races and subraces. But morphological variations of the human dentition have not been utilized to their full potential by anthropologists concerned with patterns of human biological variation in Indian population. The aim of the present study is to detect the frequency and degree of expression of Carabelli's trait in Bengaluru population, this helps to develop a probabilistic model to distinguish individuals from specific human populations, particularly for forensic purposes.

A total number 400of age and sex matched individuals from four different ethnic groups - Hindu, Islam, Christian and Iranians were examined clinically and study casts were made. Permanent maxillary first molars were examined for the expression of Carabelli's trait, Dahlberg classification system was used to score the trait on the teeth. The scores were recorded on Osteoware Dental Morphology software. The cast were examined by 2 observers independently to eliminate intra observer variation in interpretation and mean of 2 was taken for analysis. The data so obtained was statistically analysed especially emphasizing on differences between above mentioned 4 ethnic groups.

Cusp of Carabelli was present in 87% of the study population in maxillary first permanent molar. Type 3 was the most frequently expressed and Type 6 was the least frequently expressed and both type being expressed in Islamic groups. The expression of trait was bilateral in 90% of the surveyed groups.

It was concluded that the prevalence of cusp of Carabelli in the small population from Bengaluru considered in the present study was found to possess a high degree of Carabelli trait expression.