DENTAL MANIFESTATIONS OF OSTEOGENESIS IMPERFECTA AND ABNORMALITIES OFCOLLAGEN-I METABOLISM

The in vitro protein-chemical features and the molecular background of osteogenesis imperfecta (OI), a heritable disorder of collagen I meta bolism, have been elucidated in recent years. The aim of our study was to find the prevalence of dentinogenesis imperfecta (DI) and other de ntal anomalies in 88 patients with OI, to compare clinical with radiol ogic abnormalities, and to correlate these clinical/radiologic finding s with the results of gel electrophoresis and molecular studies of col lagen I. Twenty-eight percent of OI patients had DI. Most patients wit h DI had radiologic abnormalities, but some patients had radiologic si gns compatible with DI, but no clinical signs of DI. OI type I patient s with DI were more severely affected by OI than those without DI. In OI type III and IV, in contrast, there was no difference in overall se verity between patients with and without DI. DI was not associated wit h any particular molecular aberration in any OI type. If defining DI f rom the presence of both clinical and radiologic signs. collagen I pro duced by cultured fibroblasts was qualitatively abnormal from all OI p atients with DI. Some OI patients had dental abnormalities not resembl ing DI. A qualitative collagen abnormality could not be found in any o f these patients. Denticles, i.e., calcifications within the pulpal ca vity, were found more frequently in OI patients than in control subjec ts.