title: [Soft tissue changes following the treatment of Class II division 1 malocclusion using Headgear-activator appliance].
abstract: OBJECTIVE
  To investigate the soft tissue changes following the treatment of Class II division 1 malocclusion using Headgear-activator appliance.
  
  
  METHODS
  Fifty Class II division 1 malocclusion subjects who were at peak high velocity on the growth curve were divided into two groups. Standardized lateral cephalogram was taken for each patient in the two groups before and after treatment. SPSS11.0 software package was used to calculate the mean and standard deviation, matched t-test was used to evaluate the changes of the soft tissues.
  
  
  RESULTS
  The angle of CmSnLs,LiB'Pg' and Z increased, the angle of H, LsNsLi and LsNsPg' decreased, there was statistically significant difference between the two groups.
  
  
  CONCLUSIONS
  Using Headgear-activator appliances, soft tissue profile is effectively improved. Soft tissue chin is moved forward obviously. Lip protrusion is decreased.
authors: Department of Stomatology,The Bethune International Peace Hospital. Shijiazhuang 050082, China. hbliliguo@163.com
authors: Li-Guo
authors: LG
authors: Li
authors: Yan-Ping
authors: YP
authors: Zuo
authors: Dong-Hui
authors: DH
authors: Yuan
mesh_terms: D000202:Activator Appliances; D002508:Cephalometry; D002680:Chin; D005115:Extraoral Traction Appliances; D006801:Humans; D008310:Malocclusion; D008445:Maxillofacial Development; D016896:Treatment Outcome