ABSTRACT
OBJECTIVE: To evaluate the change in the soft tissue profile following mandibular setback osteotomy in Angle's class-III cases. MATERIAL and METHODS: Twenty-Five patients with skeletal class-III malocclusion were treated by presurgical orthodontics and mandibular setback osteotomy. The study was carried-out on lateral cephalograms of the patients taken before surgery and six weeks after surgery. The amount and direction of soft tissue change after mandibular setback osteotomy was evaluated. Seven soft tissue parameters were used to study the change six weeks after surgery. A-A', B-B', UI-Ls, Pog-Pog', ULS, LLS, showed decrease but LI-Li displayed increase. Upper lip thickness decreased slightly while lower lip thickness increased non-significantly. The results are suggestive of the relaxation of the lower lip after IMF period