ICD-10 K00.5 | ICD-9-CM 520.5 | |
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Dentin dysplasia is a genetic disorder of teeth, commonly exhibiting an autosomal dominant inheritance. It is characterized by presence of normal enamel but atypical dentin with abnormal pulpal morphology. There are two types. Type I is the radicular type, and type II is the coronal type. In the radicular type, the roots of teeth are shorter than normal and the pulp chamber may be nearly gone. The teeth shows extreme mobility and are exfoliated prematurely because of their short roots. The pulp chamber is sometimes described as having a "crescent shaped" appearance. In the coronal type, the pulps are enlarged and are described as having a "thistle tube" appearance, in permanent dentition. In the deciduous dentition, coronal dentin dysplasia bears a resemblance to Dentinogenesis Imperfecta type II.
Radiographic Features
Type 1: Roots are short, blunt and conical. In deciduous teeth, pulp chambers and root canals are completely obliterated while in permanent they may be crescent shaped.
Type 2: The pulp chamber of the deciduous teeth become completely obliterated. The permanent teeth displays large pulp chamber in the coronal portion of the tooth - referred to as thistle tube appearance. Pulp stones may be found.
Histologic Features
Type 1: Normal dentinal tubule formation is blocked and new dentin forms around obstacles.known as lava flowing around boulders.
Type 2 : Permanent teeth show abnormally large pulp chambers, known as Thistle tube appearance. Deciduous teeth show amorphous and atubular dentin in radicular portion, while coronal dentin is normal. The permanent teeth have multiple pulp stones.