Calcified tissues involved in the ontogenesis of the human cranial vault.

The cranial vault of fifteen human subjects varying in age from 20th week of gestational life to 9th month post-matum were submitted to microradiographic and histological analysis. Different phenomena such as cortical drift, bone cavitation and progressive substitution of different calcified tissues by lamellar bone are illustrated. Moreover, this study reveals in several areas the presence of chondroid tissue; it constitutes the edges of the sutures and is responsible for their growth till the post-natal period. Therefore, it can be supported that the role of chondroid tissue is essential for the harmonious development of the cranial vault.