title: [Non-extraction approach using RPE to correct Angle Class I malocclusion with moderate crowding: A cephalometric study].
abstract: OBJECTIVE
  To study cephalometric changes in Angle Class I malocclusion with moderate crowding treated orthodontically without extraction using rapid palatal expansion (RPE).
  
  
  METHODS
  9 patients with Angle Class I moderate crowding were orthodontically treated with a non-extraction approach using RPE and fixed edgewise appliances.The cephalometric analysis was performed at T1(pretreatment), T2(3 months after RPE) and T3(fixed retention period after active treatment).
  
  
  RESULTS
  Lateronasal width, maxillary width, upper and lower first molar width significantly increased after rapid expansion (T1-T2) and after active treatment (T1-T3) with the significant difference in upper first molar width between T2 and T3. Total facial height, upper anterior facial height, the inclination of palatal plane and Y axis increased significantly (T1-T2, T1-T3). There were significant differences in the inclination of mandibular plane among T1, T2 and T3.
  
  
  CONCLUSIONS
  Maxillary transverse width could increase using RPE. Rapid palatal expansion might not result in the anteroposterior changes.
authors.affiliation: Department of Orthodontics, Ninth People's Hospital, School of Stomatology, Shanghai Second Medical University, Shanghai 200011, China. ffgong@citiz.net
authors.forename: Fang-fang
authors.initials: FF
authors.lastname: Gong
authors.forename: Jing
authors.initials: J
authors.lastname: Lu
authors.forename: Gang
authors.initials: G
authors.lastname: Shen
mesh_terms: D002508:Cephalometry; D006801:Humans; D008311:Malocclusion, Angle Class I / Q000628:therapy*; D008437:Maxilla; D008963:Molar; D010155:Palatal Expansion Technique