title: Duration of orthodontic treatment and mandibular lengthening by means of distraction or bilateral sagittal split osteotomy in patients with Angle Class II malocclusions.
abstract: BACKGROUND
  The purpose of this study was to investigate the duration of treatment of patients with skeletal Angle Class II malocclusions treated with orthodontic appliances and surgical lengthening of the mandible to close residual overjets.
  
  
  METHODS
  In this retrospective study, the patients were divided into 3 groups. Group A consisted of 10 patients (5 boys, 5 girls; mean age, 10.11 years; range, 9.1-13.9 years at the beginning of treatment) who were treated with a headgear-activator, fixed appliances, and intraoral osteodistraction of the mandible. Group B consisted of 19 patients (10 boys, 9 girls; mean age, 12.3 years; range, 9.6-16.1 years) treated with fixed appliances and intraoral distraction. In group C, 13 patients (4 men, 9 women; mean age, 27.3 years; range, 12.11-40.7 years) were treated with fixed appliances and bilateral sagittal split osteotomy (BSSO).
  
  
  RESULTS
  In patients treated with orthodontic appliances and surgical lengthening of the mandible, treatment time was influenced by the appliances and the surgical technique used. Patients treated with a headgear-activator, fixed appliances, and intraoral distraction osteogenesis (group A) needed significantly more treatment time than patients treated with fixed orthodontic appliances and intraoral distraction (group B) or fixed appliances and BSSO (group C). Duration of treatment with intraoral mandibular distraction (group B) was significantly (P < .05) shorter compared with mandibular lengthening with BSSO (group C). However, no definitive conclusions can be drawn, because of the retrospective study design.
  
  
  CONCLUSIONS
  The best time and the best surgical procedure for correcting mandibular length have yet to be determined, and a prospective randomized trial is recommended.
authors.affiliation: breuning@orthodontics.nl <breuning@orthodontics.nl>
authors.forename: K Hero
authors.initials: KH
authors.lastname: Breuning
authors.forename: Peter J
authors.initials: PJ
authors.lastname: van Strijen
authors.forename: Birte
authors.initials: B
authors.lastname: Prahl-Andersen
authors.forename: D Bram
authors.initials: DB
authors.lastname: Tuinzing
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D005115:Extraoral Traction Appliances; D005260:Female; D006801:Humans; D007902:Length of Stay; D008297:Male; D008312:Malocclusion, Angle Class II / Q000601:surgery*; D008334:Mandible / Q000601:surgery*; D019186:Mandibular Advancement / Q000379:methods*; D009971:Orthodontics, Corrective / Q000295:instrumentation; D019857:Osteogenesis, Distraction; D010027:Osteotomy; D012189:Retrospective Studies; D013997:Time Factors