Dental anomalies in two patients with incontinentia pigmenti.

Incontinentia pigmenti (IP) is a rare X-linked dominant inherited disorder which has a variety of ectodermal aberrations. Skin hyperpigmentation is the most characteristic feature of IP. However, extracutaneous anomalies involving dentition, hair, eyes, and central nervous system are also found. The dental anomalies reported include peg-shaped or malformed teeth, hypodontia, delayed eruption, and impacted tooth. This report describes the dental anomalies in 2 IP patients who had the characteristic features of skin hyperpigmentation. One was a 13-year-old girl who had slender cone-shaped permanent anterior teeth, hypodontia, and delayed eruption of teeth which are characteristic dental anomalies in an IP patient. The other was a 10-year-old girl who only had 2 tulip-shaped maxillary permanent central incisors with shorter tapering roots but no congenital missing teeth or delayed eruption of teeth. Our findings suggest that IP may present a broad variation of dental anomalies individually. However, the characteristic finding of permanent anterior teeth with a longer crown and a shorter root found in both of our IP patients may be worthy of consideration in the differential diagnosis of IP.