Interpretation of the vertical and longitudinal growth of the human skull.

Our model describes asymptotic growth as a time-dependent process which expresses a quantitative change in individual morphological factors. The development and growth of the face are intimately connected with the cranial base, which undergoes only minor changes between the ages of 0 to 25 years. The difference in growth of the neuro- and viscerocranium is evident in that the dimensions and angles of the viscerocranium undergo greater changes than those of the neurocranium. The anterior cranial base lengthens until the end of normal growth via bone apposition at the nasion. This elongates the cranial base. The nasion influences the sagittal maxillary relationships. The posterior cranial base shows a constant growth rate up to ca. 15 years of age. The face and dentition develop along the nasion-gonion and sella-gnathion distance, which demonstrates the greatest absolute growth rate. During growth, the viscerocranium increases principally in height.