Comparison of soft tissue changes in angle class Ⅰ southern Chinese females with ELSID treated by orthodontic extraction / 中华医学美学美容杂志

ABSTRACT

Objective To find out the changes of the soft tissue profile in Guangdong women with Angle's I teeth uncovered by lips after extraction of 4 first bicuspid teeth and to evaluate its significance. Methods Fifteen cases of adult Guangdong women with Angle's I teeth uncovered by lips were enrolled in this retrospective study. The X-ray film of lateral cephalometry was used to analyze the soft tissue profile in pre- and post- corrective tooth extraction. The paired t-test was statistically applied for comparison between the changes of lip tissue in pre- and post- correction. Results The changes occurred obviously in the angles of nose vs. lip and upper vs. lower lips, angle Z, and the length, thickness, esthetical plane distance and convex distance of upper and lower lips, but not in the angles of face and facial convex, basic angle of upper vs. lower lips and chin thickness. Conclusilons The facial dislocation and figure of these women have been positively improved after extraction of 4 first bicuspid teeth in spite of the larger thickness of lips than before correction, the just partly shortened distance between lips and the upper and front teeth still exposed and uncovered by lips to some extent. Further improvement depends on functional exercise of lip muscles.