Soft tissue profile changes following correction of class III malocclusions by mandibular surgery.

The relative movement of the soft and hard tissues were studied in 41 Class III cases treated by mandibular surgery. Lateral head films were traced and the hard and soft tissue changes were measured against vertical and horizontal reference lines. In 26 cases changes occurring more than 1 year after surgery were studied. It is concluded that the soft tissues move consistently slightly less than the underlying hard tissues and also that a change in form of the lips occurred. Prediction of profile changes by the cutting up of profile photographs is unlikely to given an accurate picture of the soft tissue profile response.