title: Dentoskeletal effects of 3 maxillary expanders in patients with clefts: A cone-beam computed tomography study.
abstract: BACKGROUND
  The purpose of this study was to evaluate the skeletal and dental changes in the maxillae of patients with clefts treated with 3 expanders: hyrax, fan-type, and inverted mini-hyrax supported on the first premolars.
  
  
  METHODS
  Thirty patients with unilateral cleft lip and palate with transverse maxillary deficiency were divided into 3 groups, according to the type of expander that they used. Cone-beam computed tomography images were taken before and 3 months after expansion, and the paired t test was used to evaluate the changes in each group.
  
  
  RESULTS
  The subjects in the inverted mini-hyrax group showed significant forward displacement of the maxilla (P <0.05). On the transversal plane, the hyrax group showed greater expansion in the posterior region than in the anterior region (P <0.05). However, the fan-type and the inverted mini-hyrax groups showed significantly greater maxillary expansion anteriorly than posteriorly (P <0.05). There was a greater tendency for buccal inclination of the supporting teeth when the fan-type was used. The cleft and the noncleft sides expanded symmetrically with all appliances, and there was no difference in dental tipping between these sides (P >0.05).
  
  
  CONCLUSIONS
  The hyrax expander showed better results for cleft patients requiring anterior and posterior maxillary expansion. The inverted mini-hyrax most effectively restricted posterior expansion, optimizing anterior expansion without causing as much buccal tipping of the supporting teeth as did the fan-type.
authors: Private practice, Belo Horizonte, Brazil.
authors: Daniel Santos Fonseca
authors: DS
authors: Figueiredo
authors: Private practice, Belo Horizonte, Brazil.
authors: Flávia Uchôa Costa
authors: FU
authors: Bartolomeo
authors: Private practice, Belo Horizonte, Brazil.
authors: Camila Rodrigues
authors: CR
authors: Romualdo
authors: Associate professor and program director, Department of Orthodontics; and director of the Craniofacial Imaging Center, School of Dental Medicine, Case Western Reserve University, Cleveland, Ohio.
authors: Juan Martin
authors: JM
authors: Palomo
authors: Associate professor and dean of graduate studies, School of Dentistry, Pontifical Catholic University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
authors: Martinho Campolina Rebello
authors: MC
authors: Horta
authors: Associate professor, Department of Orthodontics, Pontifical Catholic University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
authors: Ildeu
authors: I
authors: Andrade
authors: Associate professor and program director, Department of Orthodontics, Pontifical Catholic University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil. Electronic address: dauro.bhe@gmail.com.
authors: Dauro Douglas
authors: DD
authors: Oliveira
mesh_terms: D059925:Anatomic Landmarks / Q000000981:diagnostic imaging; D002508:Cephalometry / Q000379:methods; D002648:Child; D002971:Cleft Lip / Q000150:complications*; D002972:Cleft Palate / Q000150:complications*; D054893:Cone-Beam Computed Tomography / Q000379:methods*; D003724:Dental Arch / Q000000981:diagnostic imaging; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008310:Malocclusion / Q000209:etiology / Q000628:therapy; D008437:Maxilla / Q000000981:diagnostic imaging; D009296:Nasal Cavity / Q000000981:diagnostic imaging; D016382:Orthodontic Appliance Design; D010155:Palatal Expansion Technique / Q000295:instrumentation*; D014070:Tooth / Q000000981:diagnostic imaging*; D019227:Tooth Apex / Q000000981:diagnostic imaging; D019228:Tooth Crown / Q000000981:diagnostic imaging