Nitrous oxide (N2O), more commonly referred to as laughing gas, is used as a local sedation method, according to the California Dental Association (CDA). It is colorless and odorless. Nitrous oxide is effective as a sedative because it relaxes patients with the pleasurable feelings it emits. Nitrous oxide's usefulness also stems from how quickly it works and that its effects are reversible. For those and other reasons, nitrous oxide is widely considered to be a safe sedation method.
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