title: Treatment effects of R-appliance and Fränkel-2 in Class II division 1 malocclusions.
abstract: OBJECTIVE
  The purpose of this study was to compare the effects of a differently designed functional appliance (the R- appliance) with Fränkel-2.
  
  
  METHODS
  Twenty-seven patients (16 girls and 11 boys) with a mean age of 9.8 (SD 1.6) years were treated with the R-appliance for 15.4 (SD 0.4) months and twentyseven (15 girls and 12 boys) patients with a mean age of 9.1 (SD 1.1) years were treated with a Fränkel-2 appliance for 19 (SD 5.6) months. All patients had Class II division 1 malocclusions due to mandibular deficiency and all of them had prepubertal stages of skeletal development. Lateral cephalograms obtained at the beginning (T1) and at the end (T2) of the study were analysed.
  
  
  RESULTS
  Paired t-tests showed that SNB significantly increased in both groups. The incisor mandibular plane angle (IMPA) was reduced in the R- appliance group by 2.2 (SD 4.9) degrees (P<0.03) but increased by 2.2 (SD 2.6) degrees (P<0.001) in the Fränkel-2 group. The SNA in the R-appliance group showed an increase of 0.2 (SD 2) degrees (P<0.6), while it was decreased by 0.4 (SD 0.5) degrees (P<0.6) in the Fränkel-2 group.
  
  
  CONCLUSIONS
  Both treatment modalities were successful in moving the mandible forward. However, with the R-appliance, this was achieved without proclination of the lower incisors.
authors.affiliation: Orthognathic Surgery, Department of Orthodontics, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: R
authors.initials: R
authors.lastname: Showkatbakhsh
authors.forename: M I
authors.initials: MI
authors.lastname: Castaldo
authors.forename: A
authors.initials: A
authors.lastname: Jamilian
authors.forename: G
authors.initials: G
authors.lastname: Padricelli
authors.forename: M
authors.initials: M
authors.lastname: Fahimi Hanzayi
authors.forename: S
authors.initials: S
authors.lastname: Cappabianca
authors.forename: L
authors.initials: L
authors.lastname: Perillo
mesh_terms: D002508:Cephalometry / Q000379:methods; D002648:Child; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007180:Incisor / Q000473:pathology; D008297:Male; D008312:Malocclusion, Angle Class II / Q000628:therapy*; D008334:Mandible / Q000254:growth & development / Q000473:pathology; D008437:Maxilla / Q000473:pathology; D008445:Maxillofacial Development / Q000502:physiology; D009295:Nasal Bone / Q000473:pathology; D016382:Orthodontic Appliance Design; D017289:Orthodontic Appliances, Functional; D012189:Retrospective Studies; D012658:Sella Turcica / Q000473:pathology