Variations in Structural Morphogenesis of the Human Face and Jaws

Abstract

Sufficient evidence was collected from study of 125 embryos and fetuses to indicate that characteristics exhibited in these specimens bear close resemblance to physical differences present in the living. The differences included variations in the process of ossification of the component parts of the cranium, face, and jaws, in the shape and proportions of the developed jaws, and in the relationship of upper and lower jaws. The indications are that morphogenesis of the skeletal structure and the shaping of the individual follow an inherently established pattern during embryo-fetal life. The trend toward frequent facio-jaw deformities in civilized populations is especially evident in most Europeans where random matings are common between diverse physical types often including physically defective. It appears doubtful whether undernourishment alters physical morphology of the craniofacial and jaw structures during prenatal life, except perhaps for the effects of hypocalcemia.