A study of upper lip profile change after anterior segmental setback osteotomy

ABSTRACT

PURPOSE: Prediction for soft tissue change after orthognathic surgery is very important for the final esthetics. In this study, we have tried to get the amount of upper lip movement relative to bony segment movement after anterior segmental osteotomy by cephalmetric analysis to predict final upper lip position after surgery. MATERIAL AND METHODS: 20 patients was studied on whom anterior segmental osteotmy as performed by Cupar method during the years 2002 to 2003. Cephalometric radiograph were taken at 1month before surgery and 6 month after surgery. Change of upper lip was measured on landmark Ls and Sto relative to hard tissue (landmark Ia) setback on these X-rays and analyzed. RESULTS: 1. Upper lip setback movement Setback of upper lip showed proportional relation to the hard tissue setback and the ratio was about 84 % (p=0.001). 2. Upper lip downward movement Downward movement of upper lip showed no proportional relation to hard tissue setback And the amount was mean 1.38 mm and SD 1.21mm (p=0.922). CONCLUSION: The posterior movement of upper lip is affected by hard tissue movement and shows good proportional change whereas downward movement is not so much influenced by hard tissue movement. And we think slight downward movement shown in this study could be explained by the V-Y closure performed during surgery.