Polarized Light and Microradiographic Study of Dental Tissues in Dentinogenesis Imperfecta

¹ Howard University College of Dentistry, Washington, D.C.

Morphological characteristics and variations in mineralization of plano-parallel ground sections of teeth from patients with dentinogenesis imperfecta were studied by microradiography and polarized light microscopy. Microradiographic examination revealed poorly mineralized dentin and regions of interglobular dentin. The dentin formation was haphazard and crisscrossed with wide canals and spaces. Polarized light examination showed that the tubules in the root dentin were sparse and seemed to end in angular or club-shaped dilatations or spaces. The tubules were irregular and tortuous. The roots of the teeth showed deposition of excessive amounts of lacunar (cellular) cementum. There also were many cementocyte-free lacunas, suggesting that the cementum had undergone degenerative changes. The intermediate (replacement) cementum was extremely irregular and probably represented regions of resorption and subsequent repair.

The pulp chambers were partially or completely obliterated and replaced by calcified tissues closely resembling osteodentin-like structures.