Laughing gas, or laughing gas, produces a mild depression in a region of the brain related to feelings and self-censorship. When inhaling it, the person enters a state of relaxation and happiness, and may even laugh for nothing. The feeling is similar to when you drink a little too much. It is still not known precisely what is the mechanism of action of the gas, whose correct name is nitrous oxide (N2O). It was discovered in 1772 by the English chemist Joseph Priestley. A few years later, it was found that the gas caused a pleasant sensation when inhaled. Thus, it did not take long for the substance to be “sniffed” during parties. In 1844, the American dentist Horace Wells realized that the gas had an anesthetic effect by chance: at a party, Wells noticed that one of the guests who had inhaled nitrous oxide was injured, but did not show any pain. Curious, the dentist decided to test the substance and was the first patient to have a tooth extracted after inhaling the gas. In practices in the United States, Europe and other countries around the world, nitrous oxide has long been used. In Brazil, however, it is only now gaining more fans. “The patient remains calm and conscious, which increases the safety of the dental procedure”, says dentist Luiz Alberto Ferraz de Caldas, director of the Brazilian Association of Dental Surgeons, Rio de Janeiro section.
1. Through a mask, the patient inhales a mixture of nitrous oxide and oxygen — at most 70% oxide. These two gases come out of cylinders and the mixing ratio is controlled by the dentist.
2. After being inhaled, the gas reaches the lungs. As the substance has a great capacity for expansion, it passes through the pulmonary alveoli and falls into the bloodstream.
3. The gas quickly begins to circulate through the bloodstream and heads towards the central nervous system, where nitrous oxide begins to act about 5 minutes after being inhaled by the person
4. The action of the gas is on the cerebral cortex, a region related to feelings of fear, anxiety and self-censorship. It is believed to reduce nerve transmissions in the cortex. An occasional urge to laugh is a side effect. The most important thing in the office is that the gas relaxes the patient and increases their pain tolerance, acting as an anesthetic.