[Ultrastructural and histological studies on type I osteogenesis imperfecta]

The results of 3 bone biopsies in patients with Sillence I. type of osteogenesis imperfecta are described. The biopsy material was examined with light microscope histomorphometric and various electron microscopic methods. Histomorphometry showed that the osteoid rim (OS%) and the steroid surface covered by osteoblasts (OB%) was significantly greater, in the same time the relative quantity of osteoid (Vvos%) was significantly less, compared with the normal bone. Electron microscopy showed the broadening and unevenness of the mineralization front. The diameters of the collagen fibers were quite unstable compared with the control. The structure of the newly developed apatit crystals was not different, although their measure was less than of the control. The microanalytical examinations of Ca/P relation of the crystal phase did not show any difference.