Nitrous oxide is a colourless gas that decreases pain sensitivity and gives the patient a pleasant level of sedation during dental treatment. It is safe and approved for use in dental surgeries and unlike IV sedation or general anaesthesia, the patient can almost always leave the clinic by themselves afterwards, without an escort.
Once the patient is fully relaxed, the dentist may then administer a local anaesthetic injection, as required, and begin the dental treatment. Afterwards, the patient will be given pure oxygen to breathe for about five minutes, and all of the effects of the sedation are usually reversed.
As a precaution, patients should not eat anything for about two hours prior to the use of the gas.