Nitrous Oxide Sedation is the lightest form of dental sedation, but it can provide adequate level of anesthesia and relaxation for most people and for the majority of dental procedures. It involves breathing a mixture of nitrous oxide gas in combination with oxygen which can help anxious patients to become more relaxed and co-operative during treatment without experiencing pain. This method of sedation is good for light procedures or routine visits to the dentist. It is best for people with low levels of anxiety.