Osteogenesis imperfecta: fibronectin in dentin matrix.

Deciduous and permanent teeth from seven patients with five different osteogenesis imperfecta (OI) syndromes and three normal subjects were demineralized with ethanolic trimethylammonium EDTA, enzymatically pretreated and immunostained with antihuman plasma fibronectin (FN) sera. Staining for FN in the dentin matrix was positive in halo and reticular patterns in the one patient with Sillence type I B OI and in two patients of three with type IV B OI, all with dentinogenesis imperfecta (DI). The staining was negative in type I A OI without DI, in type III, in one patient with type IV B, and in an unidentified type of OI, all with DI. In normal control teeth no staining of the dentin matrix was observed. The staining differences between OI types (also with DI) may reflect genetic heterogeneity. The diverse results in type IV B OI were suggestive of interfamilial variability within the OI syndrome. The presence of FN in the dentin matrix in OI may be due to its continuous synthesis or decreased degradation during dentin development.