806203.fig.001
Figure 1: Legan-Burstone soft tissue analysis: facial forms. Horizontal reference plane (HP), constructed by drawing a line through nasion (N) 7 degrees up from the sella-nasion line. Facial convexity angle (G-Sn-Pg′); maxillary prognathism (G vertical-Sn); mandibular prognathism (G vertical-Pg′); vertical height ratio (G-Sn/Sn-Me′); lower face-throat angle (Sn-Gn′-C); lower vertical height-depth ratio (Sn-Gn′/C-Gn′).