title: Class II treatment efficiency in maxillary premolar extraction and nonextraction protocols.
abstract: BACKGROUND
  In this study, we compared the efficiency of nonextraction and 2-maxillary-premolar-extraction protocols in complete Class II malocclusion treatment.
  
  
  METHODS
  A sample of 112 records from patients with complete Class II malocclusion was divided into 2 groups with the following characteristics: group 1, comprising 43 patients treated nonextraction with an initial mean age of 12.63 years; and group 2, comprising 69 patients treated with extraction of 2 maxillary premolars with an initial mean age of 13.91 years. To compare the efficiency of each treatment protocol, the initial and final occlusal statuses were evaluated on dental casts with the peer assessment rating (PAR) index, and the treatment time of each group was calculated from the clinical charts. Treatment efficiency was calculated by the ratio between the percentage of PAR reduction and the treatment time. PAR scores, treatment times, and treatment protocols' efficiencies of the groups were compared with the t test.
  
  
  RESULTS
  The 2-maxillary-premolar-extraction protocol had a smaller final PAR score, a greater percentage of PAR reduction, and greater treatment efficiency than the nonextraction protocol of complete Class II malocclusion.
  
  
  CONCLUSIONS
  The 2-maxillary-premolar-extraction protocol has greater treatment efficiency than the nonextraction protocol of complete Class II malocclusion.
authors.affiliation: Department of Orthodontics, Bauru Dental School, University of São Paulo, Bauru, Brazil. jansong@travelnet.com.br
authors.forename: Guilherme
authors.initials: G
authors.lastname: Janson
authors.forename: Sérgio Estelita Cavalcante
authors.initials: SE
authors.lastname: Barros
authors.forename: Marcos Roberto
authors.initials: MR
authors.lastname: de Freitas
authors.forename: José Fernando Castanha
authors.initials: JF
authors.lastname: Henriques
authors.forename: Arnaldo
authors.initials: A
authors.lastname: Pinzan
mesh_terms: D000293:Adolescent; D000704:Analysis of Variance; D001641:Bicuspid / Q000601:surgery; D002508:Cephalometry; D002648:Child; D004526:Efficiency; D005115:Extraoral Traction Appliances; D005260:Female; D006801:Humans; D008297:Male; D008312:Malocclusion, Angle Class II / Q000628:therapy*; D008437:Maxilla; D016910:Orthodontic Brackets; D009969:Orthodontic Wires; D009971:Orthodontics, Corrective / Q000295:instrumentation / Q000379:methods*; D018024:Peer Review, Health Care; D012189:Retrospective Studies; D018709:Statistics, Nonparametric; D013997:Time Factors; D014081:Tooth Extraction; D016896:Treatment Outcome