What is the cause of a carabelli cusp?

Genes are the main cause of a Carabelli Cusp. This is a condition where there is an additional cusp on the first molar of the tooth and become less pronounce when progressing to the second and third molars. In some cases, the cusps' forms included pits, ridges, and furrows. 

The Carabelli Cusp is a condition most common in Europeans and rarest in the Pacific Islands. It is an inherited feature from a homozygote or a heterozygote gene that can be present or absent in some individuals. It was discovered in the year 1842 by Georg Carabelli, a court dentist of the Austrian Emperor Franz. 

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