Dentoskeletal determinants of soft tissue morphology.

The position of the lips and the soft tissues overlying points A and B seem to be substantially related to the horizontal positions of the upper and lower incisors and to the angulation of the upper incisor. The angulation of the lower incisor is much less important than its spatial position. The A-N-B angle is strongly related to the overlying soft tissue outline. Point A convexity is a very important factor in soft tissue form. The Ricketts E line, the Steiner S line and the soft tissue facial plane all seem to be equally acceptable bases for assessment of the soft tissues of the profile.