Nitrous oxide, widely used for inhalation sedation in dentistry, could have a measurable and variable environmental impact across dental services in the UK, according to a national quality improvement project.
In the study—published in the British Dental Journal—investigators at the Eastman Dental Institute, London, analysed real-world data from 31 dental services and 891 sedation appointments to quantify the carbon footprint of dental nitrous oxide use and identify opportunities to reduce greenhouse gas emissions while preserving patient care.
Nitrous oxide is a potent greenhouse gas, with a global warming potential far exceeding that of carbon dioxide.
“[Nitrous oxide] used in dentistry has a quantifiable impact on the environment,” lead study author Alexandra Lyne wrote.
Across participating sites, the mean carbon footprint per sedation appointment was 28.62 kg of carbon dioxide equivalent, with values ranging from 10.74 to 40.67 kg of carbon dioxide equivalent. On a service level, the average weekly footprint reached 518.25 kg of carbon dioxide equivalent. Most of this impact was attributable to the nitrous oxide gas itself rather than equipment or consumables.
The investigators also documented substantial variation in how nitrous oxide is supplied and administered. Among 128 sites providing inhalation sedation, 84 per cent relied on a cylinder supply and 16 per cent used centrally piped manifold systems. The estimated wastage differed between these approaches. Average wastage was four per cent at the sites using cylinder supplies compared with 30 per cent at the sites using piped supplies.
“There is wide variation in the volumes of nitrous oxide administered to dental patients, as well as potential wastage in the supply of the gas,” the study authors noted.
All participating services used active scavenging systems, but the flow rates and administration times varied. The mean flow rate was 5.84 L per minute, and the average duration of nitrous oxide delivery was 28 minutes. The investigators found that the flow rate, rather than nitrous oxide concentration, had the greatest influence on overall emissions.
“A flow rate that is greater than clinically necessary does not hold any additional patient benefit but does increase the volume of [nitrous oxide] used, and therefore, the carbon footprint and harm to the planet,” the study authors stated.
This article was sourced from Connexiant Dental.
