title: Upper airway expansion after rapid maxillary expansion evaluated with cone beam computed tomography.
abstract: OBJECTIVE
  Cone-beam computed tomography (CBCT) is a reliable method of assessing the oral cavity and upper airways. We conducted this study to examine the changes introduced by rapid maxillary expansion in the nasal cavity, nasopharynx, and oropharynx as seen with images obtained by CBCT.
  
  
  METHODS
  We evaluated 15 patients with maxillary width deficiency treated with RME. Patients were subjected to CBCT at the beginning of RME and after the retention period of 4 months.
  
  
  RESULTS
  The nasal cavity presented a significant transverse increase in the lower third, in the anterior (1.08 mm ± 0.15), medium (1.28 mm ± 0.15), and posterior regions (0.77 mm ± 0.12). No significant change occurred in the nasopharynx in volume (P  =  .11), median sagittal area (P  =  .33), or lower axial area (P  =  .29) resulting from the RME. A significant change was noted in the oropharynx in volume (P  =  .05), median sagittal area (P  =  .01), and lower axial area (P  =  .04) before and immediately after the RME.
  
  
  CONCLUSIONS
  RME is able to increase the transverse width of the nasal cavity, but it does not have the same effect in the nasopharynx. Changes noted in the oropharynx may be due to the lack of a standardized position of the head and tongue at the time of image acquisition.
authors: Department of Orthodontics, Dentistry School, University of São Paulo, São Paulo, Brazil. annelisencr@gmail.com
authors: Annelise Nazareth Cunha
authors: AN
authors: Ribeiro
authors: João Batista
authors: JB
authors: de Paiva
authors: José
authors: J
authors: Rino-Neto
authors: Edson
authors: E
authors: Illipronti-Filho
authors: Tarcila
authors: T
authors: Trivino
authors: Solange Mongelli
authors: SM
authors: Fantini
mesh_terms: D002648:Child; D054893:Cone-Beam Computed Tomography; D005260:Female; D006801:Humans; D008297:Male; D009296:Nasal Cavity / Q000033:anatomy & histology / Q000000981:diagnostic imaging*; D009305:Nasopharynx / Q000033:anatomy & histology / Q000000981:diagnostic imaging*; D009960:Oropharynx / Q000033:anatomy & histology / Q000000981:diagnostic imaging*; D010155:Palatal Expansion Technique; D018709:Statistics, Nonparametric; D016896:Treatment Outcome