A study of the growth changes in facial configuration

In order to explore the growth changes in facial configuration, 160 subjects (80 young adults and 80 children aged 11-12) with normal occlusion were selected for roentgenocephalometric analysis. The present study led to the following conclusions: (a) The ratios of anterior upper to anterior total facial heights, anterior lower to anterior total facial heights, and anterior upper to anterior lower facial heights in both sexes stayed constant around 45, 55, and 81 per cent, respectively. (b) The change in the ratio of the posterior total to anterior total facial heights was mainly due to the greater potentiality of the posterior part of the lower face. (c) The increases of the lower anterior and posterior dental heights were larger than that of the upper anterior and posterior dental heights, respectively. The increases of the upper and lower posterior dental heights were larger than that of the upper and lower anterior dental heights, respectively. (d) On average, the mandibular plane and the occlusal plane tended to rotate forwards with age while the cant of the sella-nasion plane, the Frankfort horizontal plane, and the palatal plane remained fairly unchanged. (e) The saddle angle, the articular angle, and the FNA angle remained relatively stable with age, while the gonial angle and the FNB angle seemed to be age-related. The decrease in the size of the gonial angle might contribute mainly to the flattening tendency of the mandibular growth coincident with general growth. (f) Both the inclination of upper incisor to palatal plane and lower incisor to mandibular plane remained reasonably constant throughout maturation.(ABSTRACT TRUNCATED AT 250 WORDS)