Postnatal development of skull base, neuro- and viscerocranium in man and monkey: morphometric evaluation of CT scans...

Postnatal development of the neuro- and viscerocranium with special reference to the maxillodental structures was studied morphometrically by analyzing computer tomograms and radiograms of human and monkey heads of different age groups. The following parameters were used: the prognathic angle, the clivus angle, the palate-incisivus angle, the interincisival angle and the viscerocranial quotient. In the newborn primates including man, all parameters measured were relatively similar; postnatally, however, characteristic differences in the growth pattern between man and monkey were developing. In monkey, a marked prognathic growth of the viscerocranium was found associated with characteristic positional changes of the frontal teeth, whereas the growth of the neurocranium was retarded. Here, unlike the human, a flattening of the skull base was observed. In contrast, the human skull showed no major proportional changes during its postnatal development compared with the original spherical skull form of the newborn.