Typical Radiographic Findings of Dentin Dysplasia Type 1b with Dental Fluorosis

Dentin dysplasia is a rare inherited autosomal dominant disorder characterized by rootless teeth. We hereby report a case of dentin dysplasia type 1b with typical radiographic findings: short and blunt roots, pulpal obliteration, horizontal/crescent shaped radiolucencies in pulp chambers, and multiple periapical radiolucencies. However, the present case did not show the autosomal dominant pattern of inheritance and the patient also exhibited concurrent dental fluorosis, transposition of 13 and 14, and multiple cusps in maxillary first molars. Moreover, on careful review of previously documented cases of radiographs of dentin dysplasia, the horizontal/crescent shaped radiolucencies in pulp chambers are a rare finding, which is characteristically seen in the present case. 1. Introduction Dentin dysplasia (DD) is an autosomal dominant hereditary disturbance in dentin formation, which may present with either mobile teeth or pain associated with spontaneous dental abscesses or cysts. It is a rare anomaly of unknown etiology that affects approximately one patient in every 100,000 [1]. The condition was first described by Ballschmiede, but it was Rushton who termed the condition dentinal dysplasia. This condition is rarely encountered in dental practice. In 1972, Witkop Jr. [2] classified DD into two types: radicular DD as type I and coronal DD as type II. In type I, both the deciduous and permanent dentitions are affected. The crowns of the teeth appear clinically normal in morphology, but defects in dentin formation and pulp obliteration are present. Radiographic examination is important for the identification of DD type I. 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. The present case is dentin dysplasia type 1b with typical radiographic findings: short and blunt roots, pulpal obliteration, horizontal/crescent shaped radiolucencies in pulp chambers, and multiple periapical radiolucencies. Though dentin dysplasia is transmitted as autosomal dominant disorder, the present case did not show the autosomal dominant pattern of inheritance and the patient also exhibited concurrent dental fluorosis, transposition of 13 and 14, and multiple cusps in maxillary first molars. Moreover, on careful review of previously documented cases of radiographs of dentin dysplasia, the horizontal/crescent shaped radiolucencies in pulp chambers are a rare finding, which is characteristically seen