Short-term consequences of orthognathic surgery on stomatognathic function

Craniomandibular dysfunction, mandibular range of motion and occlusal contacts subsequent to surgical-orthodontic treatment were studied in 20 adults with Le Fort I impaction and/or advancement, 34 with vertical ramus setback, 12 with sagittal split advancement and 16 with Le Fort I impaction, and/or advancement and bilateral vertical ramus setback. All subjects were examined 1 week before surgery and 6 months post-operatively. The results of the study indicated that 6 months post-operatively: (a) There was a decrease (NS) in dysfunction patients in the maxillary and double-jaw osteotomy groups, and an increase in the mandibular advancement osteotomy sample (P < 0.05). (b) There was a significant decrease in maximal interincisal opening in both mandibular osteotomy groups (P < 0.01) and in laterotrusive movements in the mandibular advancement group (P < 0.05). (c) The number and intensity of occlusal contacts increased significantly in the maxillary and mandibular setback osteotomy groups (P < 0.01 and P < 0.001, respectively).