Soft tissue changes associated with incisor decompensation prior to orthognathic surgery.

A retrospective cephalometric study employing angular and linear measurements was undertaken to examine soft tissue changes associated with incisor decompensation prior to orthognathic surgery. Subjects were divided into 3 groups based on the presenting malocclusion, and radiographs for each subject were traced and subsequently digitized. The results showed that incisor decompensation was achieved more markedly in Class II division 2 and Class III patients. In Class II division 1 subjects, changes in the mandibular incisor inclination were contrary to what was anticipated. The soft tissue change/dental change ratio following incisor decompensation showed that the soft tissues were least affected in the Class II division 2 group. This may be due to the increased tone of the soft tissues in this group, which resisted the effects of the incisor change. Alternatively, it may indicate that the soft tissue "drape" is not in close approximation to the dentition and therefore dental changes are not transmitted to the soft tissues.