The 88th Annual Meeting of the American Association of Physical Anthropologists (2019)

Ontogeny of human cranial vault microstructure


1Univ. Lille, EA 4490-PMOI-Physiopathologie des maladies osseuses inflammatoires, Lille, France., University of Lille, 2UMR 5199, PACEA, université de Bordeaux, 33615 Pessac Cedex, France, University of Bordeaux, 3PSL University-Paris – Ecole Pratique des Hautes Etudes, University of Paris

March 29, 2019 , CC Ballroom BC Add to calendar

Human cranial vault (HCV) has a major protective role for the brain. It is formed by two dense layers of cortical bone, and a central layer of cancellous bone called the diploe. Growth, development and evolution of HCV have been widely studied by measuring thickness variations, providing strong evidences of a link with the brain and the masticatory muscles. However, little is known about the ontogenetic changes of its microstructure. The recent development of micro-computed tomography allows an accurate description of cortical and trabecular bone microarchitecture. The main goal of our study is to record the ontogenetic changes in cranial vault microstructure, from birth to 12 years old.

We selected 45 cranial vault samples of 9mm in diameter, in subadults from 3 months to 12 years old, and 5 complete skulls of newborns. Bone samples were imaged with high-resolution MicroCT (Skyscan microCT®, Bruker, Kontich, Belgium), with 5-10 microns resolutions. Applying specific cortical and trabecular thresholds, 2D and 3D microstructural parameters were measured.

We provided a detailed map of the cortical (thickness and porosities) and trabecular (number, thickness and spaces) parameters related to age. The results showed a fast individualization of outer and inner tables after birth, and the formation of an initial well organized trabecular network from 1.5 years, followed by a long period of increase in size.

This study provided new insights into the cranial vault ontogeny that could be relevant to understand the multiple factors involved in the evolution of human skull.