A comparison of the effectiveness of nitrous oxide scavenging devices

Four nitrous oxide scavenging systems were tested for their efficiency under ideal standardized conditions. The volunteers received 35% nitrous oxide for 20 minutes and the levels of nitrous oxide recorded and averaged every five minutes. No density was carried out. All four systems achieved levels below 30 parts per million. With the recommended limit for nitrous oxide levels in dental operatory being 50 parts per million (ppm) rather than the several thousand ppm reached without scavenging, it is necessary to ensure that the scavenging devices available are capable of achieving this level. To do so under normal dental operating conditions provides many variables, such as the type of procedure carried out, movement by the patient, ventilation efficiency of the operatory, type of mouth pack utilized etc. This investigation was therefore designed to eliminate all operator and procedure variabilities. Each system was evaluated under ideal identical conditions and with no actual treatment being carried out.