Nitrous oxide is also called dinitrogen monoxide, or laughing gas. One of several oxides of nitrogen, it is a colorless gas with pleasant, sweetish odor and taste, and it is nonflammable. When inhaled nitrous oxide produces relaxation, and a reduced sensibility to pain sometimes preceded by laughter, hence its common name, laughing gas. Nitrous oxide was discovered by the English chemist Joseph Priestley in 1772. Another English chemist, Humphry Davy, later named it nitrous oxide and showed its physiological effect. The principal use of nitrous oxide is as an anesthetic in medical and dental procedures of short duration. The gas is also used as a propellant in food aerosols, and as an accelerant in engines.
The usual concerns we hear expressed by people are:
The concentration of the gas can be changed to adjust the degree of effect from mild anxiety relief to feeling rather drowsy, and you determine the level that is comfortable for you. You are never out of control. The actual gas concentration you breathe is a mixture of oxygen and nitrous oxide, and can be regulated proportionally anywhere from 0% nitrous oxide to 70% nitrous oxide.
Nitrous oxide acts quickly, within a couple minutes, and its effect is eliminated just as rapidly. The only residual effect people experience is relaxation from the lack of anxiety.
Nitrous oxide is fitting whenever it is deemed appropriate by you. It can be used just for an injection or for an entire procedure - you decide this.
Disposable nose masks are available that are comfortable, scented and latex-free. These fit just over your nose to deliver the nitrous oxide (they are available in different scents and sizes).
Modern nitrous oxide delivery meters have safety / proportional fail-safe mechanisms built-in to always deliver at least 30% oxygen. In addition, scavenging systems are used to collect expired nitrous oxide gas and dispel it safely out of the office. Nitrous oxide nose masks are single-use and disposable.
Nitrous oxide may or may not be a reimbursable expense under your particular dental insurance plan.