Why don’t dentists use nitrous oxide anymore?

Throughout its history, nitrous oxide has evolved from a novelty discovery to a multifaceted tool in science, medicine and industry, while also remaining a subject of recreational use and environmental concern.

Nitrous oxide, commonly known as nitrous, laughing gas, or by its chemical formula N2O, is a colourless, non-flammable gas with a slightly sweet odour and taste. It is composed of two nitrogen atoms bonded to one oxygen atom. This gas is widely known for its use in various fields, notably in medical and recreational settings. In the medical field, nitrous oxide is valued for its anesthetic and analgesic properties.

Dentists and surgical professionals use it as a sedative due to its ability to induce relaxation and alleviate pain while maintaining the patient’s consciousness. Its fast onset and quick recovery make it a convenient option for minor procedures.

Nitrous oxide is still widely used by dentists today. It remains an integral part of dental sedation practices due to its safety, effectiveness, and rapid onset of action. Dentists use nitrous oxide to help manage pain and alleviate anxiety in patients during various dental procedures. Its continued use is especially valued for patients who experience dental fear or anxiety, as it promotes relaxation while allowing them to remain conscious and responsive.

The modern dental profession upholds the use of nitrous oxide as a reliable sedative and analgesic, maintaining its reputation as a trusted tool for improving patient comfort and procedural outcomes.

Nitrous oxide is administered in a controlled mixture with oxygen through a nasal mask, allowing patients to inhale it directly. This method ensures that its sedative effects are fast-acting, taking effect within a few minutes and inducing a state of calmness and relaxation. The gas works by depressing the central nervous system, reducing pain perception and triggering mild euphoria without causing a loss of consciousness. This allows patients to remain awake and responsive throughout the dental procedure, which is particularly beneficial for shorter or minimally invasive treatments.

Nitrous oxide is highly favored for its safety profile. It is suitable for both adults and children, making it a versatile tool in pediatric dentistry as well. Dentists appreciate its rapid onset and, equally important, its quick recovery period. After the procedure, patients can typically return to their daily activities without the lingering effects associated with other forms of sedation. To clear the gas from the patient’s system and prevent potential side effects such as headaches, oxygen is administered for a few minutes after the procedure to flush out any remaining nitrous oxide.

The history of nitrous oxide dates back to the late 18th century when it was first discovered by the English chemist Joseph Priestley in 1772. Priestley, renowned for his work with gases and discovering oxygen, found nitrous oxide while conducting experiments on the reactions between different chemicals. He described the gas in his work Experiments and Observations on Different Kinds of Air, noting its properties, but at the time, its potential uses remained unknown.

It wasn’t until the late 18th century that Humphry Davy, a British chemist and inventor, recognized the gas’s unique properties and conducted extensive research on its effects. In the 1790s, Davy inhaled nitrous oxide himself. He noted its pain-relieving qualities and euphoric effects, which he described in his 1800 publication Researches, Chemical and Philosophical: Chiefly Concerning Nitrous Oxide, or Dephlogisticated Nitrous Air, and its Respiration.
Davy famously coined the term “laughing gas” due to the lightheadedness and laughter it induced. He also speculated on its potential use in surgeries as an anesthetic, although this idea was not immediately adopted.

In the early 19th century, nitrous oxide gained popularity for recreational use, particularly in social settings known as “laughing gas parties,” where people would inhale the gas for its amusing and euphoric effects. This recreational trend spread across Europe and the United States, highlighting its effects but delaying its adoption in medical practice. It was not until 1844 that the anesthetic potential of nitrous oxide was seriously considered in a
medical context. American dentist Horace Wells attended a public demonstration where a man who inhaled nitrous oxide did not feel pain when injured. Intrigued by its potential, Wells used it on himself during a tooth extraction, successfully demonstrating that it could relieve pain. He began using nitrous oxide for dental procedures, thus becoming one of the pioneers of anesthesia in dentistry.

Despite Wells’ initial success, nitrous oxide’s use in medical procedures did not gain immediate widespread acceptance due to a failed public demonstration that damaged his reputation. However, the idea of using gases for anesthesia gradually gained traction through the 19th century, particularly after the more successful introduction of ether as an anesthetic by William T.G. Morton in 1846.

Over time, however, nitrous oxide became recognized for its efficacy and safety, especially in dental and minor medical procedures. By the late 19th and early 20th centuries, it had established its place in modern medicine.

In the 20th century, with advancements in medical technology and a better understanding of anesthesia, nitrous oxide was incorporated into medical practices as a reliable sedative and pain reliever. This period also saw its expanded use in industrial applications, including the food industry, where it became the propellant for whipped cream dispensers.

The gas is dissolved under pressure in the cream and expands when released, creating the whipped texture. Despite its legitimate uses, nitrous oxide can be misused recreationally for its euphoric and dissociative effects. When inhaled, it temporarily induces a sensation of giddiness or a brief sense of euphoria, leading to its nickname, “laughing gas.” However, recreational inhalation can pose serious health risks, including oxygen deprivation, nerve damage, and long-term neurological effects.

In the automotive world, nitrous oxide found a niche in enhancing engine performance due to its ability to deliver more oxygen for combustion. Environmentally, nitrous oxide is considered a potent greenhouse gas, contributing to climate change by trapping heat in the atmosphere. It is released through agricultural practices, the combustion of fossil fuels, and certain industrial processes. Its global warming potential is significantly higher than that of carbon dioxide, making its management crucial for environmental policies.