title: Airway compartments volume and oxygen saturation changes after rapid maxillary expansion: a longitudinal correlation study.
abstract: OBJECTIVE
  To evaluate changes in airway volumes and respiratory performance in patients undergoing rapid maxillary expansion and determine whether any correlations exist between the morphological and respiratory functional modifications induced by rapid maxillary expansion and pretreatment airway stenosis.
  
  
  METHODS
  Fifteen patients (11 females and 4 males; mean age, 7.5 ± 0.3 years) were enrolled in the study. Each patient underwent cone beam computed tomography and polysomnography examination before rapid maxillary expansion and after the removal of the maxillary expander 12 months later. The airway regions were segmented and the volumes were computed.
  
  
  RESULTS
  The upper, middle, and lower airway volumes were significantly increased 2305 mm(3), 1144 mm(3), and 1915 mm(3), respectively. Similarly, oxygen saturation was increased (+5.3%) and the apnea/hypopnea index was improved (-4.2 events). All the observed modifications were statistically significant (P < .05). Baseline middle and lower airway volume showed a significant negative correlation with the oxygen saturation modification.
  
  
  CONCLUSIONS
  The results of this study showed that when rapid maxillary expansion is performed in subjects having posterior crossbite, oxygen saturation is improved. The improvement is greater in subjects having more reduced middle and lower airway volumes.
authors.affiliation: a   Resident, Postgraduate Orthodontic Program, University of Insubria, Varese, Italy.
authors.forename: Rosamaria
authors.initials: R
authors.lastname: Fastuca
authors.affiliation: b   Research Fellow, Department of Medical, Surgical and Health Sciences, University of Trieste, Trieste, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Perinetti
authors.affiliation: c   Research Fellow, Department of Surgical and Morphological Sciences, University of Insubria, Varese, Italy.
authors.forename: Piero Antonio
authors.initials: PA
authors.lastname: Zecca
authors.affiliation: d   Assistant Professor, Department of Surgical and Dental Sciences, Section of Orthodontics, School of Dentistry, University of Messina, Messina, Italy.
authors.forename: Riccardo
authors.initials: R
authors.lastname: Nucera
authors.affiliation: e   Associate Professor and Chairperson, Orthodontic Program, Department of Surgical and Morphological Sciences, University of Insubria, Varese, Italy.
authors.forename: Alberto
authors.initials: A
authors.lastname: Caprioglio
mesh_terms: D002648:Child; D054893:Cone-Beam Computed Tomography; D003251:Constriction, Pathologic / Q000473:pathology; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008310:Malocclusion / Q000150:complications* / Q000628:therapy*; D010100:Oxygen / Q000032:analysis*; D010155:Palatal Expansion Technique; D017286:Polysomnography; D020181:Sleep Apnea, Obstructive / Q000473:pathology* / Q000628:therapy*; D013223:Statistics as Topic; D016896:Treatment Outcome
chemical_list: D010100:Oxygen
keywords: Airway; Computed tomography; Maxillary expansion; Oxygen saturation; Polysomnography