Mouth Breathing: What Every Parent Needs to Know

Most people don’t realize that mouth breathing is a complex health concern that can lead to sleep apnea, speech impediments, and improper facial growth.

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by Sarah Hornsby, RDH

Sarah Hornsby, RDH, is a myofunctional therapist based in Seattle. She is passionate about making myofunctional therapy and the problems associated with mouth breathing to be a more mainstream approach in healthcare, as she has seen first hand the serious side effects a lifetime of mouth breathing can do. Sarah offers free, 30 minute evaluations over Skype, learn more at her website.

I’m pleased to have myofunctional therapist Sarah Hornsby on the blog today to discuss mouth breathing. Most people don’t know that mouth breathing can have devastating effects on the health and development of a child, and Sarah’s article explains why mouth breathing should be taken seriously, along with some simple strategies for parents.

I’ve been a fan of Sarah’s work for some time now, which is why I asked her to write a section about myofunctional therapy for my book, The 8-Hour Sleep Paradox. She has an excellent YouTube channel for anyone who wants to learn more about how myofunctional therapy can help you stop mouth breathing, correct a reverse swallow reflex (tongue thrust), and even sleep better. If you’d like more personalized help, I recommend you book a free, 30-minute Skype consultation from her on her website—she sees patients from all over the world. —Dr. B

A mother watches her seven-year-old daughter sitting and coloring. While the girl concentrates on the shape of each petal, the mother notices something: she can see that her daughter’s lips are parted. She looks over at her son and notices his lips are closed.

Cute characteristic? Or serious sleep issue?

Most people don’t realize that mouth breathing is a complex health concern. As a myofunctional therapist, I hear stories like this all the time.

If your child is mouth breathing, s/he can learn to change the habit. That’s where I come in. It’s my job to help patients learn how to change the habit and breathe properly. Learning how to breathe through the nose instead of the mouth prevents my pediatric patients from a slew of serious health issues in adulthood, including sleep apnea, speech impediments, and improper facial growth.

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mouth breathing quick test (1) (1)For some people, an open mouth is simply a habit — their mouth rests in an open position when they’re not focused on keeping it closed. For other people, the mouth is open and used for breathing. We call this either “open mouth resting posture” or simply “open mouth.”

The natural position for healthy breathing is always with a closed mouth, inhaling and exhaling through the nose.

Some adults are very aware of their open mouth habit, while others have never noticed it until they meet me. Most of the time, my adult patients are self-conscious about their open mouth habit, and can’t understand why it’s so challenging for them to keep their lips together when they aren’t speaking or eating.

Does Mouth Breathing Actually Matter That Much?

While having an open mouth may seem like a silly thing to be concerned about, and even a simple problem to fix, it’s actually neither.

The Serious Health Effects of Mouth Breathing

  • Teeth and braces: If your mouth is open, your braces will take longer and your treatment will be much more challenging for your orthodontist. The spaces between your teeth will be more difficult to close and the stability of the alignment of your teeth will be compromised once your braces are removed. This means you are likely to experience orthodontic relapse and you may need braces again in the future.
  • Speech: When children have an open mouth, they are more likely to struggle with certain speech sounds. The most commonly associated speech problem is a lisp, or the inability to say “S” sounds correctly. Speech is affected because when you have an open mouth, you also have what we refer to as a “tongue thrust swallowing pattern.” This type of swallowing pattern causes the tongue to protrude, or push forward during speaking and swallowing.
  • Facial growth and development: It’s important to realize that growth is a very powerful force. A child with an open mouth will very likely grow into an adult with flatter facial features, less prominent cheekbones, a longer face, droopier eyes and lower facial muscle tone, a narrower palate, and even a smaller lower jaw in most cases. By closing the mouth and breathing through the nose, these negative growth patterns can be prevented.
  • Sleep and oxygen: When adults and children breathe through their mouths during the day, chances are very high that they also breathe through their mouths all night long as well. Mouth breathing at night, combined with an obstructed airway, are two symptoms directly connected to sleep apnea and altered levels of carbon dioxide and oxygen in the bloodstream. When less oxygen is able to reach the brain, learning and the ability to focus at school becomes a problem for many children. In adults, chronic fatigue, tiredness, and brain fog are common symptoms related to these issues.

When patients are referred to my office, it’s usually by their orthodontist. However, I also work with Ear, Nose, and Throat doctors (ENTs), pediatric dentists, general dentists, chiropractors, speech pathologists, allergists, and many other specialists. No matter who refers a patient or why, the first thing I screen for in every patient is an open mouth.

Megan’s Story: Seeing a Myofunctional Therapist for the First Time

When Megan came to my office for an evaluation, I asked her mother if she had allergies or anything else that could affect her breathing. I knew that if Megan had a chronically stuffy or blocked up nose, then she would have no other choice but to breathe through her mouth. It turns out that Megan did have allergies – she was allergic to cats and certain types of pollen, so this was a great place for us to start with her treatment.

After determining the cause of Megan’s open mouth, the next step was to help her fix it. By coordinating treatment with an allergist and her pediatrician, I was able to help Megan get relief from her allergy symptoms. Once she was able to breathe easily through her nose, I taught her exercises to retrain the muscles of her tongue and mouth, so that she could naturally rest her lips in a closed position. At the same time, it was important for me to teach Megan how to use her nose. After seven years of only breathing through her mouth, she needed practice using her nasal passageways.

It’s been two years since I worked with her, and Megan is now a healthy happy nine-year-old girl. She breathes through her nose and her mouth is always closed at rest. She may need braces in the future, but if she does, it will be a simple and easy process. She’ll grow into an adult with healthy facial and airway development, optimal jaw size, and a beautiful, wide smile and straight teeth.

What Causes an Open Mouth or Mouth Breathing Habit?

It can be difficult to determine the root cause of an open mouth or mouth breathing habit. However, most people tend to have one or more of these three contributing factors:

  • They have (or had) a breathing or airway problem. Just like Megan, many open mouth habits can be traced back to breathing issues such as allergies, chronic colds/stuffy noses, enlarged tonsils and adenoids, asthma, a deviated nasal septum, and much more. The interesting thing to note is that once the airway problem is resolved, the habit often still remains. I see many children who have had their adenoids removed, but still breathe through their mouth. This is where myofunctional therapy comes in – muscle, swallowing, and breathing patterns often need to be relearned after the airway obstruction is eliminated.
  • They have (or had) a thumb or finger sucking habit. When the thumb is in the mouth, especially for an extended period of time, the oral and facial muscles will develop around this habit. If the thumb is in the mouth, the lips are not able to form a seal, and a tongue thrust swallowing pattern develops as well. Just because a child stops sucking his or her thumb does not mean the mouth breathing symptoms will go away. The same thing that occurs with airway issues often occurs with sucking habits – the habit is stopped, but the mouth breathing remains. Myofunctional therapy, along with orthodontic treatment, is often needed after a thumb/finger sucking habit has been eliminated.
  • They have (or had) a tongue-tie. A tongue-tie is actually a real medical condition—not just a common expression for when someone can’t get their words out. This condition may also be referred to as a restricted lingual frenum, or a tethered tongue. If a patient has this condition, they often need their tongue released through a simple surgical procedure in order to maintain a closed mouth posture. The position of the tongue plays a very important role in nasal breathing, so if the tongue is limited by a physical restraint, it may be very difficult to stop mouth breathing. For patients who have a tongue-tie, I teach them helpful exercises before and after their surgery, and eventually, they are able to close their mouth and breathe through their nose naturally and easily.

What Parents Can Do to Prevent Mouth Breathing

Now that you are aware of these symptoms, you can look for them in yourself or your child.  You can get started by doing the following:

  1. Monitor yourself or your child for mouth breathing and/or an open mouth resting posture. How often does it occur during the day?
  2. Determine if you have any of the airway or breathing issues I mentioned above, or if you’ve had them in the past.
  3. Consider talking to a doctor or dentist who specializes in breathing and sleep. It may be time to have a sleep study done for you or your child. There are two types—at home, and in-clinic. Your doctor can help you determine the best option for you, and how to get started.
  4. Have an evaluation with a myofunctional therapist. We screen our patients for all of these symptoms, as well as many others. A myofunctional therapist will often know other specialists and will be able to point you in the right direction at the very least.

Sarah Hornsby, RDH

Learn More: When Should My Child First See the Dentist?

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