Mandibular Remodeling After Bilateral Sagittal Split Osteotomy for Prognathism of the Mandible
Purpose
To describe the postoperative remodeling changes in the mandible after bilateral sagittal split osteotomy to correct mandibular prognathism.
Patients and Methods
Twenty patients who underwent bilateral sagittal split osteotomy for the correction of mandibular prognathism were studied for postoperative remodeling changes within the mandible. The 6-week, 1-year, and long-term postoperative cephalometric mandibular tracings of 12 patients were superimposed using the fixation wires as the stable reference points to demonstrate the specific locations of the intrabony remodeling.
Results
There was a general direction of remodeling at the condylion and gonion anteriorly and superiorly, while the B point and pogonion did not show much change in remodeling. At the condylion, 60% and 40% of the cases showed significant horizontal and vertical remodeling, respectively. At the gonion, 50% and 55% of the cases showed significant horizontal and vertical remodeling, respectively. No correlation was found between the remodeling changes at condylion and gonion and the surgical movement or relapse at B point and pogonion. There was a significant correlation between the observed horizontal relapse at gonion and the horizontal remodeling changes at this point showing that the postoperative displacement of this point is a result of both positional translocation and remodeling changes.
Conclusion
The results of this study show that there are intrabony remodeling changes that occur in the mandible after sagittal split osteotomy and that these continue for a long period of time in some patients. This remodeling occurred more in the condylar and gonial areas, while the chin remained relatively stable.
⁎Professor and Director, Faculty of Dentistry, Chang Gung Memorial Hospital, Taipei, Taiwan.
†Director, Cleft Palate Team, Our Lady of Peace Hospital, Paranaque, Phillipines.
‡Assistant Professor and Chairman, Department of Orthodontics and Craniofacial Dentistry, Chang Gung Memorial Hospital, Taipei, Taiwan.
§Professor of Surgery, Chang Gung Memorial Hospital, Taipei, Taiwan.
Address correspondence and reprint requests to Dr Huang: Craniofacial Center, Chang Gung Memorial Hospital, 199 Tung-Hwa North Road, Taipei, Taiwan
ABSTRACT