Non-syndromic multiple hyperdontia in monozygotic twin sisters: a report of two cases.

Supernumerary teeth are common in the general population, with a prevalence that varies between 0.1 percent to 3.8 percent. Multiple supernumerary teeth are associated with Gardner's syndrome, Fabry-Anderson syndrome, Ehlers-Danlos syndrome, labial palatal cleft, and cleidocranial dysplasia. Multiple hyperdontia not associated with syndromes is rare and ranges between 0.04 percent to 0.1 percent. The purpose of this report was to describe the occurrence of nonsyndromic multiple hyperdontia in monozygotic twin sisters.