Interradicular dentin dysplasia associated with amelogenesis imperfecta.

Very few reports are available on the occurrence of dysplasia of both enamel and dentin. This report concerns a rare association of amelogenesis imperfecta with a dysplasia of dentin in the interradicular area in sisters of Japanese descent who have no other morphologic anomalies. Retarded tooth eruption was also a clinical feature in both sisters. Histologic examination of several teeth revealed that the anomalous interradicular dentin consisted of a mass of small, onion-like calcified bodies. The absence of any dental abnormalities in both parents, who are related as first cousins, supports the concept of autosomal recessive inheritance for this trait.