In surgical orthodontic treatment, it is necessary to evaluate the relationship between changes of hard tissue and those of soft tissue in order to predict the post-treatment soft tissue profiles of jaw deformity patients. Individual differences of patients influence the relationship between changes of hard and soft tissue. This review compares the influence of sagittal split ramus osteotomy (SSRO) with combined maxillary and mandibular ramus surgery in changes of post-treatment soft tissue profiles of skeletal mandibular prognathism. The review also compares the influence of different profile patterns in changes of post-treatment soft tissue profiles of mandibular prognathism.
Skeletal changes of SSRO influence soft tissue changes more than those of combined maxillary and mandibular ramus surgery because of differences in the postoperative tension generated in muscles and soft tissue attached to the mandible.
The post-treatment soft tissue B point was located more backwardly than the predicted point in the facial patterns with a high mandibular plane angle and a long lower anterior facial height. In the facial patterns with a low mandibular plane angle, the post-treatment line of the lower lip was positioned more inferiorly and backwardly than the predicted lower lip line.
The influence on the predictability of post-treatment soft tissue profiles might differ depending on the surgical methods and profile patterns in mandibular prognathism.
