Aim: Facial appearance is an important factor for a successful orthodontic treatment that include soft-tissue profile, finding of standard cephalometric values for various population can be useful. The aim of this study was To detect the mean soft tissue facial profile for Iranian adolescent as determined by the Holdaway analysis and also detect any differences between values of boys and girls.
Materials and Methods: Lateral cephalometric radiographs for 58 Iranian adolescent with normal occlusion were used. sample were consist of 35 girls (mean age 16y,7m) and 23 boys (mean age 15y,3m). All of subjects were positioned in cephalostat with the lips in rest and the teeth in centric occlusion. The landmarks were detected on the basis of Holdaway definition.
Results: Iranian soft tissue showed differences in some variables when comparing to Holdaway ideal values including upper lip sulcus depth, soft-tissue subnasal to H-line, inferior sulcus to H line, skeletal profile convexity and H angle, but all of them were in the normal range. Soft tissue chin thickness was the only parameter that showed differences from normal range. When comparing two sexes, upper lip thickness and soft tissue chin thickness were greater in boys in relation to girls.
Conclusions: Persian people differ from Holdaway's soft tissue norms in an increased skeletal profile convexity, H angle, and soft tissue chin thickness. These are recommended for use when formulating a treatment plan for this ethnic group. Iranian boys had thicker upper lip and greater soft tissue chin
thickness in relation to girls.