The Sagittal Growth of the Foetal Cranial Base

Abstract

There is an increase in the angular relationship between the anterior and posterior cranial components in foetal life. The angular changes taking place seem to occur in the region of the sphenoethmoidal junction. The spheno-occipital element of the cranial base showed stability during foetal life, whereas the spheno-ethmoidal part of the cranial base angles increased in the corresponding period. A large angle in any one of the cranial base angles is followed by large angles in the rest of the cranial angles. A large cranial base angle is followed by a large anterior total facial height and a relatively posterior rotation of the upper jaw, retrognathic lower face and a relatively posterior rotation of the lower jaw. The growth of the anterior cranial base is more active than the growth of the posterior cranial base. The ethmoidal and sphenoidal parts of the anterior cranial base contribute equally to the increase in length. A long anterior cranial base is followed by a large spheno-ethmoidal angle and relatively long upper and lower jaws, upper jaw prognathism, large anterior facial height and a posterior rotation of the lower jaw.