Cranial size and its relations to the length of the hard palate and retropalatal space in Japanese dry skulls.

This is a basic study designed to elucidate the correlation between the different cranial dimensions to the lengths of the hard palate and retropalatal space in dry skulls. A craniometric analysis is reported for 89 adult Japanese dry skulls. Eight dimensions were measured. The results of the study revealed that the cranial size has statistically significant correlations to the length of the hard palate and retropalatal space. It also revealed that a different pattern of correlation exists in the male and the female skulls. This study is probably the first of its kind. The results will serve as a basis for clinical research dealing with the anatomy and physiology of the palate and velopharyngeal port (velum pharyngeal musculature and pharyngeal aperture), which are concerned with normal speech formations.