Abstract
Dentinogenesis imperfecta (DI) is an inherited disorder of the dentin formation. Although the clinical and histological characteristics of the disease have been described in many reports, the pathogenesis has not been clarified.
In the present study, deciduous teeth obtained from normal individuals and four patients with dentinogenesis imperfecta were examined using newly developed histochemical methods for detection of dentin phosphoprotein. There was distinct phosphoprotein staining in the normal dentin except in the mantle dentin and in the reparative dentin, but not in the DI dentin. In addition, there were lines or granular layers, which were obviously different from both the contour lines of Owen and the granular layer of Thomes, in the external portion of the DI dentin. These may result from disturbance of the dentin formation after the initial tissue deposition.
On the basis of these results, we propose as a hypothetic interpretation of the pathogenesis of the disease that the life span of the primary odontoblasts may be severely curtailed, and the dentin formation after the degeneration of these cells may be accomplished by the immature cells of pulpal origin.
