Longitudinal changes in standing height and mandibular parameters between the ages of 8 and 17 years.

The purpose of this study was to examine the changes in mandibular dimensions and relationship as they relate to standing height, which is one indicator of skeletal maturation. The subjects for this study consisted of twenty males and fifteen females on whom cephalograms were taken between the ages of 8 and 17 years. Basic statistics summarized the changes in standing height and the mandibular parameters from 8 to 17 years of age. Analysis of variance was used to select five parameters to describe linear and angular changes in the mandible and also to compare the mean growth profiles of each of the facial parameters selected to the growth profile for standing height. Autocorrelation analysis provided a method of assessing the predictability of the growth profiles of the facial parameters from the profile of standing height for the same individual. The findings in the present investigation indicated that (1) the growth profile of height was significantly different from that of the parameters describing mandibular length and relationship; (2) the changes in standing height are significantly different in the maximum, premaximum,, and postmaximum periods of growth in both males and females; (3) the changes in mandibular length (Ar-Pog) are significantly different in the three periods; (4) the changes in mandibular relationship were not significantly different in the maximum and premaximum periods in either males or females, while the magnitude of change in the postmaximum period tended to be smaller than the other two periods; and (5) autocorrelation analysis revealed that the growth profile of height was found to have little predictive value in determining the growth profile of any of the mandibular parameters except for Ar-Pog for females.