Mouth Breathing: Causes, Treatment, And Consequences For Your Oral Health

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People occasionally breathe through their mouths if their nose is blocked. This is usually temporary and clears up as soon as the nasal congestion does. 

Mouth Breathing

But if you are constantly breathing through your mouth during the day or involuntarily during sleep, it can lead to serious health issues. According to the American Sinus Institute, mouth breathing can even change the structure of one’s face.

To treat this condition, healthcare providers may go the route of either medications or surgery. Learn more about why you should be attentive to your breathing patterns and how mouth breathing can tarnish your quality of life. 

What is mouth breathing?

Some people may have the habit of breathing through their mouth instead of their nose. This is known as chronic mouth breathing.

Mouth breathing may be aggravated by an obstruction of the nasal passages and typically only poses a risk if it prolongs for a long period.

Most people develop mouth breathing as a habitual practice when they are young children, potentially preparing the way for serious, long-term problems.

Mouth Breathing in Children

In 2015, a paper was published in the Dental Press Journal of Orthodontics titled “Guidelines proposal for clinical recognition of mouth breathing children“.

According to this paper, the guidelines proposed were made to facilitate the clinicians to differentiate between habit and obstruction when it came to mouth breathing.

They were also able to establish breathing patterns during childhood and recognized that mouth breathing was a common sleep-disordered breathing (SBD) like sleep apnea during childhood affecting a collective of 2 percent of all children.

Is it bad to breathe through the mouth?

Chronic mouth breathing can cause a lot of health problems and may eventually cause sleep disorders that can affect your day-to-day life.

In young children, mouth breathing can cause facial deformities and crooked teeth, whereas in adults, this habit may cause bad breath, tooth decay, and gum disease. 

Bad Breath (Halitosis)

Breathing through one’s mouth may also worsen symptoms of other illnesses. 

For instance, saliva is a crucial element to keep your mouth clean and healthy. Therefore, it is common for people with dry mouth (due to mouth breathing) to develop frequent yeast infections.

Why should you breathe through your nose?

Dentists emphasize the benefits that you receive when you breathe through the nose instead of the mouth. 

You may have been taught during middle school that the nose filters dust from entering the lungs. But it does so much more.

The nose produces nitric oxide which dilates and relaxes your blood vessels. Normal breathing through the nose can, therefore, improve your lung’s ability to absorb oxygen by as much as 10 to 20 percent.

Nitric oxide also has antifungal, antiviral, antiparasitic, and antibacterial properties that help the immune system in fighting infections. 

Additionally, the nose adds moisture to the air to prevent dryness in the lungs and warms up the cold air to body temperature before it enters the body.

How do I know if I breathe with my mouth open?

Mouth breathing in children is easy to look out for. However, if you’re unsure if you’re a mouth breather, you can be vigilant of these common symptoms:

  • You have been told that you snore when you sleep.
  • You constantly have a dry mouth even though you’re well-hydrated.
  • You have bad breath.
  • Your voice is constantly hoarse.
  • You wake up feeling tired and irritable every day.
  • You have frequent brain fog during the day.
  • You have dark circles under your eyes.

Symptoms of mouth breathing

In Children

Children with mouth-breathing habits may not be able to communicate their symptoms. It is important for you, as a parent, to look out for these signs to assess your child’s sleep conditions:

  • Irritability
  • Dry and possibly cracked lips
  • Slower growth rate than normal
  • Frequent crying episodes at night
  • Enlarged tonsils
  • Sleepiness during the daytime
  • Difficulty concentrating at school

Studies show that children with mouth breathing disorder can develop behavioral problems that are similar to children with attention deficit hyperactivity disorder (ADHD). Therefore, they might often be misdiagnosed as the latter.


In severe cases, mouth breathing can affect your child’s facial development, causing what is called a “mouth-breathing face”. In this condition, children have narrowed faces with receding chins or jaws.

In Adults

It is also important that you get your condition diagnosed early on if you tend to breathe through your mouth. People with mouth breathing are more likely to experience the following symptoms:

  • Dry mouth
  • Bad breath or halitosis
  • Malalignment of the upper and lower teeth
  • Drool on pillows when you wake up

Causes of Mouth Breathing

Mouth breathing occurs as a result of a partially or fully obstructed nasal airway. A variety of factors can cause mouth breathing, however, the causes can vary between mouth breathing during wakefulness and sleep.

Causes of Mouth Breathing during wakefulness 

  • Nasal Congestion: The common cause of mouth breathing when awake is nasal congestion. When nasal passages are blocked due to allergies, sinusitis, or common cold, one may switch to mouth breathing to receive adequate air.
  • Structural problems: If you have anatomical issues that cause nasal obstruction such as a deviated septum or nasal polyps, you’re more likely to breathe through your mouth than your nose.
  • Chronic allergies: Allergic reactions to dust or pollen can cause nasal congestion. Naturally, you may breathe from your mouth when that happens.
  • Environmental factors: Dry or polluted air can irritate your nose, forcing you to breathe through your mouth.
  • Habitual practice: Some people are simply used to mouth breathing due to childhood habits.
  • Anxiety or stress: At times, sudden bouts of anxiety or stress can cause shallow and rapid breathing. Most people may start mouth breathing when stressed or during panic attacks.

Causes of Mouth Breathing during sleep

  • Obstructive Sleep Apnea (OSA): It is a sleep disorder that is characterized by repeated pauses and difficulty breathing during sleep. Studies have found that children with OSA typically breathe through their mouth due to the blockage of the upper airway.
  • Nasal obstruction: Nasal congestion can cause people to sleep with their mouths open to be able to breathe properly.
  • Enlarged tonsils and adenoids: These can cause the airway to be obstructed during sleep and make it difficult to breathe normally through the nose.
  • Alcohol and sedative use: People develop mouth breathing when there is repeated use of alcohol as its relaxing effects can relax the throat muscles, causing the mouth to open during sleep.
  • Sleep position: Certain sleep positions like on the back can cause your jaw and tongue to fall backwards. This can partially block the throat and cause mouth breathing especially in children

Mouth breathing vs Nose Breathing

There are many differences between breathing through your mouth and breathing through your nose. Unsurprisingly, nose breathing has more benefits than mouth breathing.

During normal breathing through the nose, tiny hairs in your nose can filter out debris like allergens and pollution. Abnormal breathing through the mouth doesn’t offer that protection.

When the air passes through the nasal cavity during inhaling, it distributes moist and warm air to the lungs and throat. Air intake through the mouth is much drier.

Studies have also investigated the effect of mouth breathing versus nasal breathing on dentofacial and craniofacial development in orthodontic patients. 

They found that mouth breathers demonstrated greater malocclusion, higher palatal plane, and narrowing of upper and lower jaws as compared to nasal breathers.

How is mouth breathing diagnosed?

There is no single test to diagnose mouth breathing. However, the doctor may conduct breathing tests like the lip seal test to evaluate whether you breathe with your mouth closed. 

How is mouth breathing diagnosed?

During this test, the doctor holds a mirror under your nose to look for condensation or clouding to indicate that you’re breathing through your nose.

Your dentist may also examine you for swollen tonsils, nasal polyps, or other underlying conditions that may cause you to mouth breathe.

Complications of mouth breathing

Mouth breathing may be hazardous to your mouth and your body. Since breathing through your nose can be extremely drying, there will not be adequate saliva to wash away bacteria from your mouth.

Stagnant food debris and bacteria in your mouth can cause tooth decay, gum disease, and throat infections. Studies have also discovered a clear association between halitosis and mouth breathing.

Mouth breathers also have low oxygen concentration in their blood. This can lead to deadly conditions such as high blood pressure, decreased lung function, and heart failure.

In children, mouth breathing can have devastating repercussions such as changes in their facial structures. They can develop long, narrow faces with narrow mouths and gummy smiles. Overcrowding teeth may also be present.

Behavioral and cognitive challenges may also become apparent in children who are mouth breathers.

How is mouth breathing treated?

The first line of treatment addresses the cause of the condition. Medications may be prescribed for nasal congestion caused due to colds and allergies. 

Adhesive strips can be applied to the bridge of the nose to help breathing. These strips help decrease airflow resistance and help you breathe more easily through your nose.

If you suffer from obstructive sleep apnea, your doctor may recommend you use a face mask appliance at night called continuous positive air pressure therapy (CPAP). This appliance helps deliver air to your nose and prevents your airways from collapsing.

Continuous positive air pressure therapy (CPAP)

Your dental professional may also recommend you try a mouth guard to prevent your mouth from opening during the night. All you need to do is place it in your mouth at night as you sleep. To reduce mouth breathing during sleep, you can also try mouth taping.

For children, an appliance can be designed to widen the palate or roof of your mouth and help the sinuses and nasal passages open.

How to prevent mouth breathing?

It is not possible to prevent mouth breathing that is caused by the shape of your face or due to structural abnormalities in your respiratory system.

However, if you find yourself constantly stricken with a congested nose due to allergies or respiratory infections, there are certain things you can do to prevent making mouth breathing a habit.

Some tips to prevent mouth breathing include:

  • Use a saline mist during long travels.
  • Use saline nasal mists and sprays immediately during colds or allergies.
  • Sleep on your back with your head elevated to open up your airways and help breathe through the nose.
  • Keep your house allergen and dust-free.
  • Use humidifiers to keep the air in your home moist.
  • Install air filters in your air conditioning system to prevent the spread of allergens in your home.
  • Be conscious of breathing through your nose during the day.
  • Try breathing exercises like yoga or meditation to deep breathe through the nose.


Mouth breathing can not only cause problems for adults but can also hamper development in children. Various health issues such as apnea can lead to mouth breathing.

If you’re breathing through your mouth during sleep, you may have sleep apnea. Consult with your dentist or doctor to seek treatment for your condition.

For mouth-breathing children, it is best to seek medical attention as soon as a problem before any major health problems develop.

In the meantime, you should always try and make a conscious effort to breathe through the nose instead of the mouth.

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