title: Soft tissue changes associated with first premolar extractions in adult females.
abstract: BACKGROUND
  The potential for premolar extractions to produce changes in the soft tissue profile after orthodontic treatment is controversial.
  
  
  OBJECTIVE
  To evaluate the soft tissue changes associated with four first premolar extractions in adult females of South Indian ethnicity.
  
  
  METHODS
  Pre- and post-treatment lateral cephalometric radiographs of 30 adult female patients of South Indian ethnicity with bimaxillary dentoalveolar protrusion, requiring premolar extractions as a part of their orthodontic treatment, were used. The radiographs were traced and changes in three angular and 12 linear measurements measured relative to the perpendicular to the horizontal reference line, 7 degrees down from S-N through S. Correlation coefficients between the changes in the upper and lower incisors and the lip measurements were calculated.
  
  
  RESULTS
  All linear and angular measurements, except for changes in upper and lower lip thickness, B' point and the anterior point on the lower lip, showed statistically significant (p < 0.05) changes with treatment. A significant negative correlation was found between upper incisor change and nasolabial angle change and a significant positive correlation was found between upper incisor change and retraction of the most anterior point on the upper lip.
  
  
  CONCLUSIONS
  Extraction of the four first premolars followed by the retraction of incisors reduced the dental and soft tissue protrusion found in adult South Indian females with bimaxillary dentoalveolar protrusion.
authors.affiliation: College of Dental Sciences, Davangere, Karnataka, India. viral.kachiwala@gmail.com
authors.forename: Viral A
authors.initials: VA
authors.lastname: Kachiwala
authors.forename: Anmol S
authors.initials: AS
authors.lastname: Kalha
authors.forename: Genevive
authors.initials: G
authors.lastname: Machado
mesh_terms: D000328:Adult; D001641:Bicuspid / Q000601:surgery*; D002508:Cephalometry / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D007180:Incisor / Q000503:physiopathology; D007194:India; D008046:Lip / Q000033:anatomy & histology*; D008310:Malocclusion / Q000628:therapy*; D009971:Orthodontics, Corrective / Q000379:methods; D012044:Regression Analysis; D014081:Tooth Extraction