Histomorphological and chemico-physical analyses of the mineral matrix of micropetrotic human bone.

Micropetrotic areas of human bone were analyzed with reference to their distance from blood vessels and to the age of the subjects. Undecalcified bone sections were treated with various solvent, soaking and etching substances to establish the nature of the material occluding the osteocytic canalicular cavities, and were examined by means of microradiographic and microdurimetric methods and X-ray microanalysis to evaluate the degree of mineralization in the bone matrix. Since it was only after strong etching with HCl that the canalicular network became visible under light and scanning electron microscopy, it is clear that the debris filling the canalicular network consists almost entirely of mineral substance. The degree of mineralization of micropetrotic bone is high because it is always a more mature type of bone, but the mineral content of the matrix and the Ca/P ratio do not differ significantly from those of neighbouring bone where the canalicular network is fully pervious.