LONGITUDINAL SHAPE CHANGES OF THE NASAL DORSUM

This investigation quantifies childhood and adolescent growth changes of the upper and lower nasal dorsum and evaluates various aspects of t he persons' morphology that relate to shape changes of the dorsum. A l ongitudinal sample of 37 French-Canadian girls, each having cephalogra ms at 6, 10, and 14 years of age, was evaluated. The 6- to 1O-year int erval was chosen to represent childhood growth; the 10- to 14-year int erval represented adolescent growth. The upper dorsum rotates upward a nd forward (counterclockwise) approximately 10 degrees between 6 to 14 years of age. The lower dorsum shows both downward and backward (cloc kwise) and upward and forward (counterclockwise) rotation average chil dhood and adolescent changes in angulation were not significant. The r esults clearly indicate that changes in the nasal dorsum are most clos ely related to angulation changes of the lower dorsum, particularly du ring adolescence. The [ower dorsum rotates downward and backward in pe rsons who show greater vertical and less horizontal growth changes. Ro tational changes of the lower dorsum are most closely related with ver tical changes at pronasale.