Physical properties of upper and lower lips in young black adults

Abstract

Impaction group: 1. The horizontal change in the nasal tip and the base of the upper lip was unpredictable, but substantial movement was noted. 2. The upper lip followed closely the movement of the maxillary central incisor in the horizontal plane. 3. The mandibular soft tissue followed the skeletal mandibular autorotation on an approximately 1: 1 basis, except for the horizontal change in the lower lip which fell slightly lingual to the arc of rotation. 4. The lower border of the upper lip moved superiorly approximately 40 percent of the vertical maxillary change. 5. There was a reduction in the length of the vermilion border of the upper lip. 6. There was a superior vertical change in all of the maxillary soft-tissue points, which increased progressively as the soft-tissue outline was followed from the nasal tip to the lowermost point on the upper lip. 7. The stepwise regression equations increased the predictability of the soft-tissue change for several of the landmarks. Advancement group: 1. A progressive increase in the horizontal softtissue movement of the profile was followed from the tip of the nose to the free end of the upper lip was observed. 2. The horizontal movement of the mandibular soft tissue was unpredictable; however, it was proposed that this would be similar to the soft-tissue change observed in the impaction group. Reviews and abstracts 265