Correlated variation between the lateral basicranium and the face: A geometric morphometric study in different human groups

Abstract

The significance of the cranial base in the contribution of normal and pathologic facial patterns is uncertain. The aim of this study was to explore and compare patterns of morphological covariation between the face and the lateral basicranium (anterior and middle cranial fossae) with covariation patterns between the face and the midline cranial base. We employed 2D geometric morphometrics and partial least squares analysis to quantify and compare correlation coefficient between principal variation patterns between basicranial and facial structures in lateral radiographs from 143 humans from Japan (N=45), Europe (N=65) and Africa (N=34). In both comparisons basicranial patterns co-varied with dolichofacial and brachyfacial morphologies. The findings showed that the midline cranial base is not significantly correlated of common facial patterns (r=0.37, P=0.09). Instead, the lateral basicranium is significantly (P=0.000), and significantly higher (r=0.6) correlated with facial variation than is the midline cranial base. The lateral basicranium may be of higher morphogenetic relevance for influencing facial variation than previously thought. This influence may be of clinical importance for the generation of skeletal class II or class III malocclusions. Further research should expand on geometric morphometric analysis of ontogenetic and clinical 3D data in order to advance in the understanding of these complex developmental relationships.