title: The Effect of Various Concentrations of Nitrous Oxide and Oxygen on the Hypersensitive Gag Reflex.
abstract: The purpose of this study was to compare the effectiveness of various concentrations of N2O/O2on obtunding a hypersensitive gag reflex. We hypothesized that the administration of nitrous oxide and oxygen would obtund a hypersensitive gag reflex enough to allow a patient to tolerate the placement and holding of a digital x-ray sensor long enough to obtain a dental radiograph. Volunteers claiming to have a hypersensitive gag reflex were first screened to validate their claim and then tested by placing a size 2 digital x-ray sensor in the position for a periapical radiograph of the right mandibular molar area and holding it in place for 10 seconds. Subjects were first tested using room air only, then 30%, 50%, or 70% nitrous oxide until they were able to tolerate the sensor without gagging or discomfort. A visual analog scale was used for subjective responses, and other statistical tests were used to analyze the results. We found that for some subjects, 30% nitrous oxide was sufficient; for others, 50% was needed; and for the remainder of the subjects, 70% was sufficient to tolerate the test. Using a combination of 70% nitrous oxide and 30% oxygen allowed all patients claiming to have a hypersensitive gag reflex to tolerate the placement and holding of a digital x-ray sensor long enough to take a periapical radiograph.
authors.affiliation: Resident, Postgraduate Endodontic Program, School of Dental Medicine, Case Western Reserve University, Cleveland, Ohio.
authors.forename: Candace K E
authors.initials: CK
authors.lastname: De Veaux
authors.affiliation: Assistant Professor, Department of Endodontics, School of Dental Medicine, Case Western Reserve University, Cleveland, Ohio.
authors.forename: Thomas A
authors.initials: TA
authors.lastname: Montagnese
authors.affiliation: Assistant Professor, Department of Pediatric Dentistry, School of Dental Medicine, Case Western Reserve University, Cleveland, Ohio.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Heima
authors.affiliation: Assistant Professor, Department of Endodontics, School of Dental Medicine, Case Western Reserve University, Cleveland, Ohio.
authors.forename: Anita
authors.initials: A
authors.lastname: Aminoshariae
authors.affiliation: Associate Professor and Chair, Department of Endodontics, and Director, Postgraduate Endodontic Program, School of Dental Medicine, Case Western Reserve University, Cleveland, Ohio.
authors.forename: Andre
authors.initials: A
authors.lastname: Mickel
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D005683:Gagging / Q000502:physiology*; D006801:Humans; D006967:Hypersensitivity / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D009609:Nitrous Oxide / Q000008:administration & dosage*; D010100:Oxygen / Q000008:administration & dosage*; D011446:Prospective Studies; D064232:Visual Analog Scale
chemical_list: D009609:Nitrous Oxide; D010100:Oxygen
keywords: Dental radiographs; Gag reflex; Hypersensitive gag reflex; Nitrous oxide and oxygen