Facial morphology changes after total maxillary setback osteotomy.

Purpose: To evaluate the morphologic outcome after total maxillary setback osteotomy (TMSO) in dentofacial Class II deformity patients with marked upper jaw prognathism.
Patients and Methods: The assessments of 9 patients before and after TMSO were compared. The evaluation was based upon x-ray superimpositions and standardized photographic comparison. TMSO was performed through a conventional Le Fort I operation with resection of the inferior end of the pterygoid processes.
Results: All patients presented with marked upper jaw prognathism initially and have had a bimaxillary surgery with a mean maxillary setback of 3.1 mm. All patients ended in Class I occlusion after at least 1-year of follow-up. An opening of the nasolabial angle (mean 8.9 degrees) was noted for all but 2 patients. At the same time, the suborbital profile was nicely modified as a result of substantial heightening of the prezygomatic soft tissues in all patients, even without vertical maxillary intrusion.
Conclusions: These results challenge the notion of unavoidable facial alteration commonly associated with upper setbacks. TMSO allows combining satisfactory functional and cosmetic results for a number of carefully selected patients. Pronounced maxillary protrusion with acute nasolabial angle is a prerequisite. The release of the deforming strains of the dysmorphosis upon the midface will improve the suborbital profile. Bimaxillary surgery is recommended to leverage the setback and the opening of the naso-labial angle.
(Copyright 2010 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.)