title: Treatment of posterior crossbite comparing 2 appliances: a community-based trial.
abstract: BACKGROUND
  The aim of this community-based trial was to compare the effectiveness of the quad-helix appliance and removable plates for treating posterior crossbite.
  
  
  METHODS
  Ninety-nine patients were randomly divided into 3 groups: quad-helix, expansion plate, and untreated. All subjects were in the mixed dentition, had posterior crosssbite, no sucking habits, no previous orthodontic treatment, and no Class III malocclusion. The following aspects were evaluated: posterior crossbite correction, maxillary and mandibular intermolar and intercanine expansions, length of treatment, cost-benefit analysis, success rate, and number of complications.
  
  
  RESULTS
  The length of treatment and the costs were higher in the expansion plate group than in the quad-helix group. The success rates were similar for the quad-helix and the expansion plate groups, and the number of complications was higher in the quad-helix group. No self-correction was observed in the untreated group, and relapses occurred in both experimental groups.
  
  
  CONCLUSIONS
  The average treatment time was significantly shorter and 11% less expensive than in the quad-helix group, making it the more cost-effective choice for treatment.
authors.affiliation: Department of Pediatrics, University of Pernambuco, Recife, Pernambuco, Brazil. fabianagodoy10@gmail.com
authors.forename: Fabiana
authors.initials: F
authors.lastname: Godoy
authors.forename: Juliana
authors.initials: J
authors.lastname: Godoy-Bezerra
authors.forename: Aronita
authors.initials: A
authors.lastname: Rosenblatt
mesh_terms: D000293:Adolescent; D002648:Child; D015331:Cohort Studies; D003362:Cost-Benefit Analysis; D003481:Cuspid / Q000473:pathology; D003724:Dental Arch / Q000473:pathology; D003818:Dentition, Mixed; D004868:Equipment Failure; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008310:Malocclusion / Q000628:therapy*; D008334:Mandible / Q000473:pathology; D008437:Maxilla / Q000473:pathology; D008963:Molar / Q000473:pathology; D016382:Orthodontic Appliance Design; D009967:Orthodontic Appliances / Q000009:adverse effects / Q000191:economics; D010155:Palatal Expansion Technique / Q000009:adverse effects / Q000191:economics / Q000295:instrumentation*; D011446:Prospective Studies; D012008:Recurrence; D013997:Time Factors; D016896:Treatment Outcome