Nitrous oxide in dentistry

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Nitrous oxide in dentistry

Sedation by inhalation. Laughing gas. Relative analgesia. Sedative analgesia. Happiness gas. Gas and air. Nitrogen. Diazo oxide. Nitrous oxide. N2O-O2…

This practice has more names than any other sedation technique!

And rightly. Sedation by inhalation with nitrous oxide (N2O) and oxygen (O2) is described as “the almost perfect clinical sedative technique”…

What is nitrous oxide? And what does it do?

Nitrous oxide (whose formula is N2O) is simply a gas that you can breathe in. It has no colour or smell and does not irritate.

It was discovered in 1772 by Humphrey Davy (1778-1829), one of the pioneers of laughing gas experimentation. Davy described the effects on himself by self-administration for a toothache and gum infection as follows:

“One day, when the inflammation became really annoying, I breathed in three large doses of nitrous oxide. After the first four or five inspirations the usual feeling. And after a few minutes, the pain was swallowed by the pleasure.”

Sounds fun!!! The above extract pretty much sums up the effects of nitrous oxide. Eliminates pain and induces a pleasant feeling.

How to say: sedative analgesia! After about 5 minutes of gas inhalation, you get a feeling of euphoria throughout the body.

You feel drunk and happy. Some people also report pleasant visual and auditory “hallucinations”. However, we know that it is safe to use for longer periods when mixed with oxygen (O2).

In our dental practice in Rome we have used nitrous oxide since 2013.

The “laughing gas” used today by the dentist, but not only, is called N2O-O2, as it contains at least 30% of oxygen (the minimum concentration that the “sedation machine” allows to deliver).

A mixture of 70% oxygen and 30% nitrous oxide is generally used.

Children use a 50% mix of oxygen and nitrous oxide.

What is nitrous oxide used for in our dental practice in Rome?

We use nitrous oxide for virtually any dental procedure. Not only in children but also in adults who are afraid of the dentist, a situation known as dental phobia.

You are generally afraid of the dentist for previous negative, even traumatic experiences.

In our dental practice in Rome, patients are pampered from the moment they enter; nitrous oxide is the icing on the cake.

By the way, I recommend watching these videos on YouTube:

Depending on the concentration and duration of laughing gas administration, four levels of sedation can be tested (after an initial feeling of stunning):

  1. a tingling sensation, especially in the arms and legs, quickly followed by
  2. a feeling of warmth, and
  3. a feeling of well-being, euphoria and/or floating.
  4. At a deeper level of sedation, drowsiness, difficulty in keeping your eyes open or talking, nausea may appear. Which means you’re overmedicated. No worries: just tell your dentist, so that he can adjust the N2O percentage; alternatively, just take off the mask and breathe in the air.

During relative analgesia, or sedative analgesia, you should stay within the first three stages.

The concentration of N2O should always be gradually increased at each visit, because individual tolerance may vary from day to day.

If in the past you have had bad experiences with laughing gas, it is highly likely that these were due to improper administration and too high concentration of N2O.

Interestingly, the mechanism of action of N2O is still unknown (there seem to be several different mechanisms at work)!

However, it has been observed that protoxide numbs almost all forms of sensation – especially hearing, touch and pain, and seems to disinhibit some emotional centres of the brain.

The ability to concentrate or perform intelligent acts is only minimally affected, as is memory.


The equipment used for the administration of the “gas of happiness” at the dentist is quite simple. It consists of gases compressed in cylinders and a system that transfers the gas to the patient; there are also some flow regulators that can mix the correct amount of gas.

I personally use the only digital equipment available on the dental market today, the Matrx Digital MDM distributed in Italy by Reinhold. This machine is able to control second by second the temperature and pressure of the outgoing gas and thus ensure the correct volume of gas administered. The desired mix of N2O-O2 is transported through a tube to which a scented nasal mask is attached (vanilla, strawberry, bubble gum, orange) Just breathe normally with your nose and… BINGO!


Nitrous oxide works very quickly – within 20 seconds it reaches the brain. And relaxation and pain suppression is achieved in 2 to 3 minutes.

The depth of inhalation sedation can be continuously modulated. This allows the operator administering the gas to increase or decrease the depth of sedation.

Other techniques of conscious sedation have a fixed duration of action (as medicines have their own specific action time). Nitrous oxide can be administered for the exact time needed.

There is no “hangover” effect. The gas is removed from the body within 3-5 minutes after interruption of administration of the protoxide/oxygen mixture. You can safely drive and do not need to be accompanied.

With the sedation machine , the dentist can easily administer incremental doses of protoxide until the desired action is achieved (this process is called “titration”). Thus the dentist has virtually absolute control of the action of the drug, preventing the possibility of an accidental overdose.

For some procedures, those involving gums rather than teeth (such as deep teeth cleaning), the dentist can only use nitrous oxide instead of local anaesthesia.

This gas raises the pain threshold and has a local anaesthetic effect on mucous membranes and soft tissues, like gums, that’s why we talk about sedative analgesia.

However, the pain-relieving effects vary greatly from person to person.

Sedation by inhalation is very safe. It has very few side effects and has no negative effects on the heart, lungs, liver, kidneys or brain.

Sedative analgesia is very effective in eliminating, or at least minimising, the vomiting reflex.

Personally, without the sedation, I couldn’t even get a fingerprint. And I wouldn’t even get a teeth cleaning!

Who needs sedative analgesia at the dentist?

Everyone needs Sedative Analgesia at the dentist.

There is no patient, adult or child, phobic or indifferent, quiet or agitated, fearful or courageous, who cannot benefit from it:

phobics, who otherwise would hardly let himself be treated.

children, as it’s not easy to collaborate sometimes.

handicapped people, who are able to avoid general anaesthesia.

adults, who find a definitive and pleasant solution to his anxieties.

dentists, who can finally focus only on their work.

hygienists, who no longer have to worry about the patient being in pain.

Patients at ‘risk’, to whom stress can be the cause of the disease up to the most serious consequences.


When is it used?


The most invasive and gory operations, or even the longest, are those that most frighten the patient and most need sedation.

But even in the simplest surgery, sometimes from the point of view of the dentist, the patient’s mood benefits from this treatment.

In teeth cleaning sessions where the patient feels, if not great pain, certainly a discomfort if not performed under anaesthesia.

While taking dental impressions, because it eliminates the vomiting reflex.

In root planing, where the sensitivity of the teeth or gum inflammation makes it problematic to go deep without causing pain.

To probe periodontal pockets.

In the maintenance of hygiene, implantology and periodontology.

Important for the success of treatment and in the invasive and gory operations that worry the patient.

Because Nitrous Oxide desensitises oral mucosa and it raises the pain threshold.

Enhances the effect of anaesthetic.

Minimises the feeling of passing time.

It removes anxiety, fear, stress, discomfort, shame, restlessness, nervousness and impatience.

It disinhibits, makes one euphoric and leaves a pleasant feeling of well-being.

Nitrous Oxide is an exhilarating gas and, for this, everyone likes it.

Are there any contraindications?

Not recommended in the first 3 months of pregnancy, but not after. (click here to learn more)

Drug addict.

Subjects in antidepressant treatment with neuroleptics or lithium salts.

Acute lung infections.

Serious mental illness.

Perforation of the tympanic membrane

Replacement of the vitreous of the eye!

How do I know it’s for me?

Ask me to try it for 15 minutes You can’t do without it!

Careful though: not all dentists can use nitrous oxide.

AIFA (Agenzia Italiana del Farmaco) clarified in the Dear Doctor Letter that:

“Nitrous oxide should only be used in the presence of medical or dental personnel with adequate cardiopulmonary resuscitation training (BLS-D)”.

Obviously I have the operator certification of BLS-D. And in my practice there is a semi-automatic defibrillator. As described in this article .

Your tranquillity,
my challenge.

I believe that anyone, even the most fearful, should have access to dental care. I want to take care of you and make you live an enjoyable experience in my practice. This is why every appointment is unique, made of honest and ethical treatments, listening and concrete attention.