title: Higher effective oronasal versus nasal continuous positive airway pressure in obstructive sleep apnea: effect of mandibular stabilization.
abstract: BACKGROUND
  In some individuals with obstructive sleep apnea (OSA), oronasal continuous positive airway pressure (CPAP) leads to poorer OSA correction than nasal CPAP. The authors hypothesized that this results from posterior mandibular displacement caused by the oronasal mask.
  
  
  OBJECTIVE
  To test this hypothesis using a mandibular advancement device (MAD) for mandibular stabilization.
  
  
  METHODS
  Subjects whose OSA was not adequately corrected by oronasal CPAP at pressures for which nasal CPAP was effective were identified. These subjects underwent polysomnography (PSG) CPAP titration with each nasal and oronasal mask consecutively, with esophageal pressure and leak monitoring, to obtain the effective pressure (Peff) of CPAP for correcting obstructive events with each mask (maximum 20 cmH2O). PSG titration was repeated using a MAD in the neutral position. Cephalometry was performed.
  
  
  RESULTS
  Six subjects with mean (± SD) nasal Peff 10.4±3.0 cmH2O were studied. Oronasal Peff was greater than nasal Peff in all subjects, with obstructive events persisting at 20 cmH2O by oronasal mask in four cases. This was not due to excessive leak. With the MAD, oronasal Peff was reduced in three subjects, and Peff <20 cmH2O could be obtained in two of the four subjects with Peff >20 cmH2O by oronasal mask alone. Subjects' cephalometric variables were similar to published norms.
  
  
  CONCLUSIONS
  In subjects with OSA with higher oronasal than nasal Peff, this is partially explained by posterior mandibular displacement caused by the oronasal mask. Combination treatment with oronasal mask and MAD may be useful in some individuals if a nasal mask is not tolerated.
authors.forename: Marta
authors.initials: M
authors.lastname: Kaminska
authors.forename: Andree
authors.initials: A
authors.lastname: Montpetit
authors.forename: Annie
authors.initials: A
authors.lastname: Mathieu
authors.forename: Vincent
authors.initials: V
authors.lastname: Jobin
authors.forename: Florence
authors.initials: F
authors.lastname: Morisson
authors.forename: Pierre
authors.initials: P
authors.lastname: Mayer
mesh_terms: D000328:Adult; D000368:Aged; D045422:Continuous Positive Airway Pressure / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008334:Mandible; D008875:Middle Aged; D020181:Sleep Apnea, Obstructive / Q000628:therapy*