title: [The effect of orthodontic treatment on facial profile of patients with Class II division 1 malocclusions].
abstract: OBJECTIVE
  The purpose of this study was to determine the effect of orthodontic treatment on facial esthetic changes of Class II division 1 malocclusions through visual analogue scale(VAS) scores before and after treatment.
  
  
  METHODS
  Reference photographs were selected first. 40 males and 40 females were randomly selected from the patients treated in our hospital. A set of photographs of each patient were shown to a panel .Then each face profile was rated on a VAS. Means and standard deviations (SD) were calculated for each set of photographs. One male and one female's photographs with an average aesthetic score close to the median value and lower SD were then selected to serve as reference photographs. Forty Class II division 1 malocclusion patients were randomly selected. A set of standardized photographs  together with a set of reference photographs of the same gender were placed in random order to show to the panel.Facial aesthetics of the experimental subjects were scored on a VAS. Then the VAS scores both pretreatment and posttreatment were compared and analyzed using SPSS11.0  software package by one sample t test and paired t test.
  
  
  RESULTS
  Two sets of reference photographs of one male and one female were selected. The mean of the patients prior to treatment was 43.839, and 48.328 after treatment. When the population mean was supposed to be 50,significant difference was noted prior to treatment with one sample t Test(P<0.05),while no significant difference was found after treatment(P>0.05). Paired t test showed that post-treatment scores were significantly higher than pre-treatment(P<0.01).
  
  
  CONCLUSIONS
  The facial esthetic of Class II division 1 malocclusions were worse than the average, but can be improved through orthodontic treatment to approach an level.
authors.affiliation: Department of Orthodontics, Wenzhou Medical College, Wenzhou, China. ys8252000@yahoo.com.cn
authors.forename: Song
authors.initials: S
authors.lastname: Yi
authors.forename: Xin-ping
authors.initials: XP
authors.lastname: Lin
authors.forename: Rong-dang
authors.initials: RD
authors.lastname: Hu
authors.forename: Zhen-yu
authors.initials: ZY
authors.lastname: Ni
mesh_terms: D004954:Esthetics; D005145:Face; D005260:Female; D006801:Humans; D008297:Male; D008310:Malocclusion; D009970:Orthodontics; D010781:Photography