More on vault thickness. As we commented in the previous post, the cranial vault can be divided in three layers: external table, diploe and internal table. Many previously studies provided information about skull thickness and density, but generally were based on a scarce number of measurements and with limited small sample size. Digital anatomy allows to go beyond many limits and constraints when working on this topic. Arne Voie and coauthors published a study based on parametric mapping and quantitative analysis of the human cranium. This team from San Diego, California, working mainly on neuroscience and radiological investigations, described how the thickness and density of the human skull changes depending on the anatomical regions (frontal, temporal, parietal and occipital bones). Measurements were computed on 51 dried crania of modern humans (males and females, ranging from 53 to 97 years old) and were analyzed by using 2000 points positioned on the three layers. Thickness and density distribution were calculated by using an algorithm to detect dense point of both extra and intra cranial boundaries and the lower density values of the diploic layer. The density results were mapped parametrically on each cranium to display their thicker areas and their distribution. The analysis evidenced a marked variation among the specimens. The thicker regions of the skull, namely the parietal, occipital, and frontal bones, have a mean value of 10.14 mm. In almost half of the sample the denser areas are the coronal and sagittal sutures, especially in their meeting point, while in the rest of the sample the density varies widely. The study cannot evidence sexual differences in both thickness and density.
Gizéh Rangel de Lázaro