Nitrous oxide is a non-irritating, colourless, and sweet-smelling gas that is entirely safe to breathe. It has been the primary form of sedation in dentistry for many years. The patient receives mainly oxygen (50-70%) with no less than 30% nitrous oxide.

Throughout the sedation, the patient can independently breathe, retain all bodily functions, and remain in control. While under the effects of nitrous oxide, the patient may experience drowsiness and mild amnesia, which can contribute to making the dental procedure more manageable and comfortable.