A retrospective analysis of the stability and relapse of soft and hard tissue change after bilateral sagittal split osteotomy for mandibular setback of 64 Taiwanese patients.

Abstract

PURPOSE:

This study was an analysis of the soft and hard tissue changes of the facial profile after bilateral sagittal splitting osteotomy for mandibular setback of Taiwanese patients.

PATIENTS AND METHODS:

We collected pre- and postsurgical lateral cephalographs of 64 patients (28 males, 36 females) with skeletal Class III malocclusion who received combined orthodontic-surgical treatment with bilateral sagittal splitting osteotomy mandibular setback at Taipei Veterans General Hospital between 1994 and 2000. Nineteen cephalometric parameters of (14 linear, 4 angular, and the BS index) soft and hard tissues were measured at 1 week before treatment, and 2 months and 1 year after surgery, and analyzed by paired t test.

RESULTS:

Mean patient age was 20.0 +/- 1.6 years. The patients underwent an average of 7 mm mandibular setback at the osseous pogonion (Pog). Average setbacks at Pog and soft tissue pogonion (pog) were 5.54 mm and 4.85 mm, respectively, at 1 year after surgery. The setback ratio of Pog/pog was 1:0.88. The hard tissue relapse at Pog was 21% at 1 year after surgery. Improvement in prognathic profile was demonstrated by significant changes in the positions of Pog and pog, ANB angle, the distance from lower lip to esthetic line (E-L lip), and the BS index after surgery. However, compared with parameters obtained from a normal Taiwanese population, the cephalometric data of Pog, pog, and BS index still indicated mild prognathism.

CONCLUSION:

Although mandibular prognathism could be grossly improved by bilateral sagittal splitting osteotomy mandibular setback, a significant amount of relapse occurred within 1 year after surgery. The extent of the postoperatively preserved features showing mandibular prognathism should be a concern for both patients and physicians.

• Authors: Joe I-Chiang Chou, Hwai-Jen Fong, Shou-Hsin Kuang, Lin-Yang Gi, Fang-Yi Hwang, Yu-Chieng Lai, Richard Che-Shoa Chang, Shou-Yen Kao
• Journal: Journal of oral and maxillofacial surgery : official journal of the American Association of Oral and Maxillofacial Surgeons (J Oral Maxillofac Surg) Vol. 63 Issue 3 Pg. 355-61 (Mar 2005) ISSN: 0278-2391 [Print] United States
• PMID: 15742287 (Publication Type: Comparative Study, Journal Article, Research Support, Non-U.S. Gov't)

Topics

• Adult
• Cephalometry
• Chin (pathology)
• Face
• Female
• Follow-Up Studies
• Humans
• Lip (pathology)
• Male
• Malocclusion, Angle Class III (pathology, surgery)
• Mandible (pathology, surgery)
• Maxilla (pathology)
• Nose (pathology)
• Osteotomy (methods)
• Prognathism (pathology, surgery)
• Recurrence
• Retrospective Studies
• Taiwan