title: Effect of mandibular position on upper airway collapsibility and resistance.
abstract: It has been proposed that advancement of the mandible is a useful method for decreasing upper airway collapsibility. We carried out this study to test the hypothesis that mandibular advancement induces changes in upper airway patency during midazolam sedation. To explore its effect, we examined upper airway pressure-flow relationships in each of 4 conditions of mouth position in normal, healthy subjects (n = 9). In the neutral position, Pcrit (i.e., critical closing pressure, an index of upper airway collapsibility) was -4.2 cm H(2)O, and upstream resistance (Rua) was 21.2 cm H(2)O/L/sec. In the centric occlusal position, Pcrit was -7.1 cm H(2)O, and Rua was 16.6 cm H(2)O/L/sec. In the incisor position, Pcrit was significantly reduced to -10.7 cm H(2)O, and Rua was significantly reduced to 14.0 cm H(2)O/L/sec. Mandibular advancement significantly decreased Pcrit to -13.3 cm H(2)O, but did not significantly influence Rua (22.1 cm H(2)O/L/sec). We conclude that the mandibular incisors' position improved airway patency and decreased resistance during midazolam sedation.
authors.affiliation: Nagasaki University Graduate School of Biomedical Sciences, Course of Medical and Dental Sciences, Department of Translational Medical Sciences, Division of Clinical Physiology, 1-7-1 Sakamoto, Nagasaki-shi, 852-8588, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Inazawa
authors.forename: T
authors.initials: T
authors.lastname: Ayuse
authors.forename: S
authors.initials: S
authors.lastname: Kurata
authors.forename: I
authors.initials: I
authors.lastname: Okayasu
authors.forename: E
authors.initials: E
authors.lastname: Sakamoto
authors.forename: K
authors.initials: K
authors.lastname: Oi
authors.forename: H
authors.initials: H
authors.lastname: Schneider
authors.forename: A R
authors.initials: AR
authors.lastname: Schwartz
mesh_terms: D000328:Adult; D000402:Airway Obstruction / Q000503:physiopathology*; D000403:Airway Resistance / Q000187:drug effects / Q000502:physiology*; D003768:Dental Occlusion, Centric; D006801:Humans; D006993:Hypnotics and Sedatives / Q000008:administration & dosage / Q000494:pharmacology; D007180:Incisor / Q000033:anatomy & histology; D001239:Inhalation / Q000187:drug effects / Q000502:physiology; D007320:Inspiratory Capacity / Q000187:drug effects / Q000502:physiology; D008297:Male; D008334:Mandible / Q000033:anatomy & histology*; D019186:Mandibular Advancement / Q000295:instrumentation; D008874:Midazolam / Q000008:administration & dosage / Q000494:pharmacology; D017286:Polysomnography; D011312:Pressure; D012123:Pulmonary Ventilation / Q000187:drug effects / Q000502:physiology
chemical_list: D006993:Hypnotics and Sedatives; D008874:Midazolam