title: Effects of the pendulum appliance, cervical headgear, and 2 premolar extractions followed by fixed appliances in patients with Class II malocclusion.
abstract: BACKGROUND
  In this retrospective study, we compared the cephalometric effects, the dental-arch changes, and the efficiency of Class II treatment with the pendulum appliance, cervical headgear, or extraction of 2 maxillary premolars, all associated with fixed appliance therapy.
  
  
  METHODS
  The sample of 82 patients with Class II malocclusion was divided into 3 groups: group 1 patients (n = 22; treatment time, 3.8 years) were treated with the pendulum appliance and fixed orthodontic appliances. Group 2 patients (n = 30; treatment time, 3.2 years) were treated with cervical headgear followed by fixed appliances; group 3 patients (n = 30; treatment time, 2.1 years) were treated with 2 maxillary premolar extractions and fixed appliances. The average starting ages of the groups ranged from 13.2 to 13.8 years. Data were obtained from serial cephalometric measurements and dental casts. The dental casts were analyzed with the treatment priority index. The treatment efficiency index was also used.
  
  
  RESULTS
  The 3 treatment protocols produced similar cephalometric effects, especially skeletally. Comparisons among the 2 distalizing appliances (pendulum and cervical headgear) and extraction of 2 maxillary premolars for Class II treatment showed changes primarily in the maxillary dentoalveolar component and dental relationships. The facial profile was similar after treatment, except for slightly more retrusion of the upper lip in the extraction patients. The treatment priority index demonstrated that occlusal outcomes also were similar among the groups. The treatment efficiency index had higher values for the extraction group.
  
  
  CONCLUSIONS
  The effects of treatment with the pendulum appliance or cervical headgear and extraction of 2 maxillary premolars associated with fixed appliances were similar from both occlusal and cephalometric standpoints. Class II treatment with extraction of maxillary teeth was more efficient because of the shorter treatment time. Differences in maxillary incisor retraction should be noted, but these differences might have been due to greater maxillary dentoalveolar protrusion in the extraction group before treatment.
authors: Department of Orthodontics, Bauru Dental School, University of São Paulo, São Paulo, Brazil.
authors: Renata Rodrigues
authors: RR
authors: de Almeida-Pedrin
authors: José Fernando Castanha
authors: JF
authors: Henriques
authors: Renato Rodrigues
authors: RR
authors: de Almeida
authors: Marcio Rodrigues
authors: MR
authors: de Almeida
authors: James A
authors: JA
authors: McNamara
mesh_terms: D000293:Adolescent; D000704:Analysis of Variance; D001641:Bicuspid; D002508:Cephalometry; D003131:Combined Modality Therapy; D017050:Episode of Care; D005115:Extraoral Traction Appliances; D005260:Female; D006801:Humans; D008297:Male; D008312:Malocclusion, Angle Class II / Q000628:therapy*; D009967:Orthodontic Appliances; D009971:Orthodontics, Corrective / Q000295:instrumentation* / Q000379:methods; D012189:Retrospective Studies; D014081:Tooth Extraction; D014087:Tooth Movement Techniques / Q000295:instrumentation*; D016896:Treatment Outcome