The prevalence and expression of primary double teeth in western India.

Double primary teeth occur in a sample of children from western India at a prevalence rate of 1.5 percent with no sex predilection, typically occurring unilaterally, and without preference for involvement of the central incisor and lateral incisor or the lateral incisor and canine. A higher incidence of fusion over gemination was also found. An examination of the world-wide distribution of the trait suggests European and European-derived populations exhibit universally low incidences, while Asian and Asian-derived populations exhibit relatively higher frequencies. The intermediate incidence reported for western India is in agreement with previous findings with primary dental morphology, suggesting an intermediate genetic affiliation between Asian and European samples.