title: Relationship between malocclusion severity and treatment success rate in Class II nonextraction therapy.
abstract: BACKGROUND
  The purpose of this study was to evaluate the treatment success rate of Class II malocclusion without extractions, according to initial severity.
  
  
  METHODS
  Class II subjects (n = 276) were divided into 2 groups according to the severity of the malocclusion. Group 1 comprised 144 patients with bilateral half Class II malocclusion at the initial mean age of 12.27 years. Group 2 comprised 132 patients who initially had bilateral complete Class II malocclusion at the initial mean age of 12.32 years. The patients' initial and final study models were evaluated with Grainger's treatment priority index. Chi-square tests were used to test for differences between the 2 groups for categorical variables. Variables regarding occlusal results were compared with independent t tests.
  
  
  RESULTS
  Group 1 had a significantly better final occlusal result, a shorter treatment time, and a higher treatment efficiency index.
  
  
  CONCLUSIONS
  Based on these results, it was concluded that bilateral half Class II malocclusion has a better treatment success rate than bilateral complete Class II malocclusion when treatment is conducted without extractions.
authors.affiliation: Department of Orthodontics, Bauru Dental School, University of São Paulo, Bauru, SP, Brazil. jansong@travelnet.com.br
authors.forename: Guilherme
authors.initials: G
authors.lastname: Janson
authors.forename: Fabrício Pinelli
authors.initials: FP
authors.lastname: Valarelli
authors.forename: Rodrigo Hermont
authors.initials: RH
authors.lastname: Cançado
authors.forename: Marcos Roberto
authors.initials: MR
authors.lastname: de Freitas
authors.forename: Arnaldo
authors.initials: A
authors.lastname: Pinzan
mesh_terms: D000293:Adolescent; D002508:Cephalometry; D002648:Child; D003766:Dental Occlusion; D003818:Dentition, Mixed; D019229:Dentition, Permanent; D005115:Extraoral Traction Appliances; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008312:Malocclusion, Angle Class II / Q000145:classification / Q000628:therapy*; D003765:Models, Dental; D024343:Open Bite / Q000145:classification / Q000628:therapy; D016910:Orthodontic Brackets; D010347:Patient Care Planning; D012189:Retrospective Studies; D012690:Serial Extraction; D013997:Time Factors; D014087:Tooth Movement Techniques / Q000295:instrumentation; D016896:Treatment Outcome