Journal of Dental Research, Vol 70, 1286-1289, Copyright © 1991 by International & American Associations for Dental Research Online Journals
Influence of operatory size and nitrous oxide concentration upon scavenger effectiveness
R. J. Henry and R. E. Primosch
Department of Pediatric Dentistry, University of Florida College of Dentistry, J. Hillis Miller Health Center, Gainesville 32610-0426.
Concern regarding environmental health hazards for dental personnel
chronically exposed to waste nitrous oxide (N2O) prompted this
investigation. The influence on ambient N2O levels of scavenging, operatory
size, and N2O concentration delivered to the patient was evaluated during
treatment of 36 pediatric dental patients. The results showed that
scavenging significantly reduced ambient N2O levels measured at 50-56 cm
from the patient's nose. Scavenged ambient N2O levels were also observed to
decrease when N2O concentrations administered to the patient were reduced
from 50 to 30%. This concentration effect was not observed in the
non-scavenged groups. ANOVA showed that operatory size exerted a
non-significant influence on ambient N2O. The data collected during routine
treatment of pediatric dental patients demonstrated that the scavenging
system tested significantly reduced waste N2O in the operator's breathing
zone, nearly approximating the 25-ppm recommendation established by the
National Institute for Occupational Safety and Health (NIOSH).
