title: Long-term skeletal and dental stability after orthognathic surgery of the maxillo-mandibular complex in Class II patients with transverse discrepancies.
abstract: BACKGROUND
  Two-jaw surgery has become the standard procedure for correcting skeletal maxillo-mandibular discrepancies in adults. However, only a few studies have reported on the long-term stability of bimaxillary orthognathic surgery in patients with Class II malocclusion and transverse discrepancies. In this study, the long-term outcome of two-piece maxillary treatment during bimaxillary surgery in patients with skeletal Class II malocclusion was examined and the results are discussed.
  
  
  METHODS
  Dental plaster casts and lateral cephalograms of 47 patients were collected in five phases of treatment: baseline (t1), preoperatively (t2), postoperatively (t3), at the end of orthodontic treatment (t4), and at the time of long-term follow-up (t5), and were retrospectively analyzed.
  
  
  RESULTS
  At follow-up all patients showed a Class I occlusion. The maxillary width was, on average, enlarged by 2.7 mm surgically. During the following 8.8 years after treatment, 1.7 mm were lost. The cephalometric analyses showed no severe changes in the sagittal maxillary position for the duration of follow-up. The sagittal mandibular position (SNB) was changed significantly by the mandibular advancement from 75.4° to 77.8° and remained stable for 8.8 years postoperatively.
  
  
  CONCLUSIONS
  Bimaxillary surgery with two-piece maxillary treatment in patients with Class II malocclusion leads to stable long-term occlusal results in the sagittal plane. The transverse enlargement achieved by intraoperative widening does not remain stable over the years. A relapse of about 60% of the surgically expanded transverse width is seen. In Class II deformities without an open bite, where extended transverse enlargement is necessary, a two-step procedure with primary surgically-assisted rapid palatal expansion followed by one-piece surgery should be planned.
authors: Department of Oral and Maxillofacial Surgery, Paracelsus Medical University Salzburg, Müllner Hauptstr. 48, 5020 Salzburg, Austria. Electronic address: c.brandtner@salk.at.
authors: Christian
authors: C
authors: Brandtner
authors: Department of Oral and Maxillofacial Surgery, Paracelsus Medical University Salzburg, Müllner Hauptstr. 48, 5020 Salzburg, Austria.
authors: Johannes
authors: J
authors: Hachleitner
authors: Department of Oral and Maxillofacial Surgery, Paracelsus Medical University Salzburg, Müllner Hauptstr. 48, 5020 Salzburg, Austria.
authors: Christian
authors: C
authors: Rippel
authors: Department of Oral and Maxillofacial Surgery, Paracelsus Medical University Salzburg, Müllner Hauptstr. 48, 5020 Salzburg, Austria.
authors: Christian
authors: C
authors: Krenkel
authors: Department of Oral and Maxillofacial Surgery, Paracelsus Medical University Salzburg, Müllner Hauptstr. 48, 5020 Salzburg, Austria.
authors: Alexander
authors: A
authors: Gaggl
mesh_terms: D000328:Adult; D002508:Cephalometry / Q000379:methods; D003724:Dental Arch / Q000033:anatomy & histology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008312:Malocclusion, Angle Class II / Q000601:surgery*; D008334:Mandible / Q000033:anatomy & histology / Q000601:surgery*; D019186:Mandibular Advancement / Q000379:methods; D008437:Maxilla / Q000033:anatomy & histology / Q000601:surgery*; D003765:Models, Dental; D009971:Orthodontics, Corrective / Q000379:methods; D056948:Orthognathic Surgical Procedures / Q000379:methods*; D019340:Osteotomy, Le Fort / Q000379:methods; D059229:Osteotomy, Sagittal Split Ramus / Q000379:methods; D010155:Palatal Expansion Technique / Q000295:instrumentation; D012008:Recurrence; D012189:Retrospective Studies; D016896:Treatment Outcome
keywords: Class II; Maxillary transverse deficiency; Orthognathic surgery