title: Esthetic perception of changes in facial profile resulting from orthodontic treatment with extraction of premolars: A systematic review.
abstract: The authors conducted a systematic review to assess changes in patients' facial profiles resulting from orthodontic treatment with and without extraction of 4 premolars and to identify cephalometric parameters that can assist decision making in borderline cases.
  
  
  
  The authors conducted a systematic review of randomized clinical trials and observational studies comparing the 2 types of treatment (with and without premolar extraction) in terms of the changes in facial profile. The authors conducted an electronic search of the databases the Cochrane Library, PubMed MEDLINE, Embase, and Latin-American and Caribbean Health Sciences Literature.
  
  
  
  The authors identified 1 clinical trial with 26 participants and 5 observational cohort studies, collectively involving 362 participants. The authors assessed cephalometric parameters and esthetic outcomes. Four studies used linear regression analysis to investigate esthetic interaction between treatment strategy and initial lower lip protrusion. The 4 studies determined that if the initial lip protrusion was beyond a determined point, esthetic preferences favored extraction, and if the initial lip protrusion was not to that point, esthetic preferences favored conservative treatment.
  
  
  
  The results of the authors' systematic review found no significant differences between the groups in terms of the esthetic outcomes. The cephalometric parameter of initial lip protrusion can help with decision making in borderline cases.
authors: Walter
authors: W
authors: Iared
authors: Edina Mariko
authors: EM
authors: Koga da Silva
authors: Wagner
authors: W
authors: Iared
authors: Cristiane
authors: C
authors: Rufino Macedo
mesh_terms: D001641:Bicuspid / Q000601:surgery*; D002508:Cephalometry; D004955:Esthetics, Dental / Q000523:psychology; D005145:Face / Q000033:anatomy & histology; D006801:Humans; D009971:Orthodontics, Corrective / Q000379:methods / Q000523:psychology*; D014081:Tooth Extraction / Q000523:psychology
keywords: Orthodontics; cephalometry; esthetics; evidence-based dentistry; malocclusion; tooth extraction