title: A retrospective study of Class II mixed-dentition treatment.
abstract: OBJECTIVE
  To consider the effectiveness of early treatment using one mixed-dentition approach to the correction of moderate and severe Class II malocclusions.
  
  
  METHODS
  Three groups of Class II subjects were included in this retrospective study: an early treatment (EarlyTx) group that first presented at age 7 to 9.5 years (n = 54), a late treatment (LateTx) group whose first orthodontic visit occurred between ages 12 and 15 (n = 58), and an untreated Class II (UnTx) group to assess the pretreatment comparability of the two treated groups (n = 51). Thirteen conventional cephalometric measurements were reported for each group and Class II molar severity was measured on the study casts of the EarlyTx and LateTx groups.
  
  
  RESULTS
  Successful Class II correction was observed in approximately three quarters of both the EarlyTx group and the LateTx group at the end of treatment. EarlyTx patients had fewer permanent teeth extracted than did the LateTx patients (5.6% vs 37.9%, P < .001) and spent less time in full-bonded appliance therapy in the permanent dentition than did LateTx patients (1.7 ± 0.8 vs 2.6 ± 0.7years, P < .001). When supervision time is included, the EarlyTx group had longer total treatment time and averaged more visits than did the LateTx group (53.1 ± 18. 8 vs 33.7 ± 8.3, P < .0001). Fifty-five percent of the LateTx extraction cases involved removal of the maxillary first premolars only and were finished in a Class II molar relationship.
  
  
  CONCLUSIONS
  EarlyTx comprehensive mixed-dentition treatment was an effective modality for early correction of Class II malocclusions.
authors.forename: Heesoo
authors.initials: H
authors.lastname: Oh
authors.forename: Sheldon
authors.initials: S
authors.lastname: Baumrind
authors.forename: Edward L
authors.initials: EL
authors.lastname: Korn
authors.forename: Steven
authors.initials: S
authors.lastname: Dugoni
authors.forename: Roger
authors.initials: R
authors.lastname: Boero
authors.forename: Maryse
authors.initials: M
authors.lastname: Aubert
authors.forename: Robert
authors.initials: R
authors.lastname: Boyd
mesh_terms: D000293:Adolescent; D002508:Cephalometry / Q000379:methods / Q000706:statistics & numerical data; D002648:Child; D003818:Dentition, Mixed; D019229:Dentition, Permanent; D005260:Female; D006801:Humans; D008297:Male; D008312:Malocclusion, Angle Class II / Q000000981:diagnostic imaging / Q000628:therapy*; D008963:Molar / Q000000981:diagnostic imaging; D009967:Orthodontic Appliances; D009971:Orthodontics, Corrective / Q000379:methods; D012189:Retrospective Studies; D013997:Time Factors; D014081:Tooth Extraction; D014087:Tooth Movement Techniques / Q000295:instrumentation / Q000379:methods*; D016896:Treatment Outcome
keywords: Class II malocclusion; Early treatment; Mixed dentition; Retrospective study