MedGen

Some researchers believe that dentinogenesis imperfecta type II and type III, along with a condition called dentin dysplasia type II, are actually forms of a single disorder. The signs and symptoms of dentin dysplasia type II are very similar to those of dentinogenesis imperfecta. However, dentin dysplasia type II affects the primary teeth much more than the permanent teeth.

Researchers have described three types of dentinogenesis imperfecta with similar dental abnormalities. Type I occurs in people who have osteogenesis imperfecta, a genetic condition in which bones are brittle and easily broken. Dentinogenesis imperfecta type II and type III usually occur in people without other inherited disorders. A few older individuals with type II have had progressive high-frequency hearing loss in addition to dental abnormalities, but it is not known whether this hearing loss is related to dentinogenesis imperfecta.

Dentinogenesis imperfecta is a disorder of tooth development. This condition causes the teeth to be discolored (most often a blue-gray or yellow-brown color) and translucent. Teeth are also weaker than normal, making them prone to rapid wear, breakage, and loss. These problems can affect both primary (baby) teeth and permanent teeth. [from MedlinePlus Genetics]

Dentin dysplasia type II (DTDP2) is a defect of dentin formation in which the clinical appearance of the secondary teeth is normal, but the primary teeth may appear opalescent, similar to teeth affected by dentinogenesis imperfecta. The roots of the teeth are of normal shape and morphologic character. The pulp chambers and root canals of the anterior teeth and the premolars are shaped like thistle tubes because of the radicular extension of the pulp chamber. Most teeth show accumulations of pulp stones in these unusually shaped pulp chambers (summary by Kalk et al., 1998). Also see dentin dysplasia type I (DTDP1; 125400). [from OMIM]

Dentinogenesis imperfecta, Shields type III (DGI-III) is an autosomal dominant disorder of dentin formation. DGI presents clinically with gray to brownish-blue discoloration of the teeth and rapid attrition of the crowns, which are bulbous. There are no skeletal manifestations. Both deciduous and permanent teeth are affected (summary by MacDougall et al., 1999). [from OMIM]