title: Comparison of the effects of face mask treatment started simultaneously and after the completion of the alternate rapid maxillary expansion and constriction procedure.
abstract: OBJECTIVE
  To test the null hypothesis that there were significant differences for skeletal, dentoalveolar, and soft tissue changes induced by face mask (FM) started simultaneously and after an alternate rapid maxillary expansion and constriction (Alt-RAMEC) procedure.
  
  
  METHODS
  Thirty-six patients with Class III malocclusion due to maxillary deficiency were randomly assigned to Group I (FM started after the completion of the Alt-RAMEC) and Group II (FM started simultaneously with the Alt-RAMEC). The screw of the RME appliance was alternately activated and deactivated twice daily (0.20 mm per turn) for 1 week over the course of 8 weeks. The changes observed in both groups were assessed using the cephalometric lateral films and statistically evaluated using the paired t-test and Student's t-test.
  
  
  RESULTS
  Thirty patients completed the present prospective study. No significant differences were observed between the groups. Class III malocclusion and negative overjet were improved by means of skeletal changes in conjunction with upper incisor proclination in both groups. Skeletal contribution to overjet correction in Groups I and II was 91.70% and 86.10%, respectively. Maxilla showed a forward movement of 3.84 mm and 3.02 mm in Groups I and II, respectively.
  
  
  CONCLUSIONS
  The null hypothesis was rejected. Both groups showed similar results, and, thus, waiting until completion of the Alt-RAMEC procedure for the FM treatment is not necessary.
authors.affiliation: a Research Assistant, Department of Orthodontics, Faculty of Dentistry, Karadeniz Technical University, Trabzon, Turkey.
authors.forename: Bilge H
authors.initials: BH
authors.lastname: Canturk
authors.forename: Mevlut
authors.initials: M
authors.lastname: Celikoglu
mesh_terms: D000539:Alveolar Process / Q000473:pathology; D059925:Anatomic Landmarks / Q000473:pathology; D002508:Cephalometry / Q000379:methods; D002648:Child; D005115:Extraoral Traction Appliances; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007180:Incisor / Q000473:pathology; D008297:Male; D008313:Malocclusion, Angle Class III / Q000628:therapy*; D008334:Mandible / Q000473:pathology; D008437:Maxilla / Q000473:pathology; D009295:Nasal Bone / Q000473:pathology; D016382:Orthodontic Appliance Design; D057887:Overbite / Q000628:therapy; D010155:Palatal Expansion Technique / Q000295:instrumentation; D011446:Prospective Studies; D012658:Sella Turcica / Q000473:pathology; D013997:Time Factors
keywords: Alt-RAMEC; Class III; Face mask; Maxillary protraction