Stimson, P.G.; Mertz, C.A. (2002). Forensic Dentistry. CRC Press. p. 11. ISBN978-1-4200-4831-5. Retrieved 2023-10-19. Carabelli's tubercle or cusp is an anomalous cuspule on the mesiolingual surface of maxillary incisors appearing in 50% of American whites, 34% of Afro-Americans and 5-20% of American Indians.