This is a relatively new term to me for having been a dental hygienist for over 30 years. I am still a bit stunned and dismayed by the fact that I have not heard of this sooner. I am bringing awareness to topics like this one and more that will change how we look at our kids and their health as they grow and develop, starting with the mouth and how they breathe at an earlier age.
I like to start with breathing. It is the first thing we do when we are born, and it is essential to how we grow and develop.
Why is breathing essential to life?
Most living things need oxygen to survive. Oxygen helps organisms grow, reproduce, and turn food into energy. Humans get the oxygen they need by breathing through their nose and mouth if they have no other option into their lungs. Oxygen gives our cells the ability to break down food to get the energy we need to survive and thrive.
It’s important to pay attention to how you breathe. In general, it’s healthier to breathe through your nose instead of your mouth. That’s because nose breathing is more natural and helps your body effectively use the air you inhale and get it to the parts of the body that need it.
On the physiological level, breath is literally life. The oxygen we take into our bodies through breath is processed through our lungs and heart into our blood, where it is transferred throughout the body to every single cell. Our brain needs oxygen to focus.
When we breathe through our nose, we get 18% more oxygen than our bodies need.
If you are a nose breather, the tongue creates a good definition of cheekbones and a wider face through force exerted against your jaw. Tongues of mouth breathers have nowhere to rest, resulting in facial structure changes as time goes on.
How does mouth breathing affect people?
People who breathe through their mouths and not their noses are more likely to develop sleep disorders, including sleep apnea. Children with mouth breathing are more likely to have dental problems like malocclusion and facial differences. This is why airway orthodontics is something we all need to know about.
Breathing through your mouth might seem harmless but will lead to a variety of problems. Your teeth and health become compromised when you inhale primarily through your mouth. Teeth, jaws, and nasal cavities are negatively affected by chronic mouth breathing. With the help of your dentist, you can correct these issues and discover ways to start breathing through your nose.
Crooked Teeth and Poor Facial Structure
Your dental and facial structure starts developing in the womb. The breathing routine you get accustomed to carries on into your later life. How you breathe helps form muscles in your face, neck, and jaw. Properly functioning muscles allow your tongue to rest against your inner jaw, developing the shape of your teeth.
Did you know your tongue is strong enough to exert 500 grams of force or 1 pound of pressure on your teeth every time you swallow?
It only takes 1.7 grams of force to move a tooth, so your tongue has enough strength to overpower your teeth. This 100% muscle organ determines the size and shape of your upper jaw. When you are a mouth breather, your tongue gets lost in your mouth. Without your tongue pressing force against the roof of your mouth, your top jaw becomes too narrow. A narrow jaw means your teeth have little or no room to grow, resulting in crooked teeth and a smaller airway.
Your habits will impact your facial structure.
If you are a nose breather, the tongue creates a good definition of cheekbones and a wider face through force exerted against the hard palate. Tongues of mouth breathers have nowhere to rest, resulting in facial structure changes as time goes on. If you are a chronic mouth breather, your face will be narrow with poor definition in your cheekbones, and the roof of your mouth will be more narrow. When breathing through your mouth, you tend to tilt your head backward, increasing cranial contents in the back portion of your brain. This has a direct result on your posture and the shape of your face and neck.
Identifying mouth breathing at a young age will help improve the way your jaw and teeth grow. When left too long, the situation becomes chronic and requires intervention methods to correct the problem. Your jaw can get altered and teeth straightened with various types of orthodontic tools, from palatal expanders to braces. It is best to identify and monitor the situation early on. By starting at an early age, a solid routine will positively impact your facial structure and teeth growth.
The food we eat and chew also plays an important role in jaw development.
Before Agriculture, Human Jaws Were a Perfect Fit for Human Teeth.
The emergence of the agricultural revolution initiated major changes to the jaw structure of ancient humans, leading to dental problems we still experience, which is why more and more people require braces. Braces are no longer just for vanity to straighten teeth. We need them to restore function and breathing.
Evolutionary biologist Daniel Lieberman notes the pattern in his book, The Story of the Human Body, “Most of the hunter-gatherers had nearly perfect dental health. Apparently, orthodontists and dentists were rarely necessary in the Stone Age.”
There weren’t any advancements in the teeth straightening method until the 18th century when in 1728, Pierre Fauchard wrote a book titled “The Surgeon Dentist” and talked about a Bandeau device that looked like a mouthguard and helped teeth stay in their correct position.
Malocclusion and dental crowding arose 12,000 years ago with the earliest farmers. Summary: Hunter-gatherers had almost no malocclusion and dental crowding, and the condition first became common among the world’s earliest farmers. It changed how we eat and chew, which has changed how our jaws develop. Called Malocclusion.
Malocclusion is a misalignment or wrong relation between the teeth of the two dental arches (maxilla and mandible) once they approach each other because the jaws close. The term was coined by Edward Angle, known as the “father of modern orthodontics.”
The genius of Edward Hartley Angle (1855-1930) was to create order from chaos in the study and treatment of positional discrepancies of the teeth, jaws, and face, which greatly advanced the cause of dental public health.
Angle’s innovations that had the most public health impact were:
- Identification of dental occlusion, not simply tooth irregularity
- Development of an uncomplicated classification system for occlusal conditions
- Introduction of prefabricated orthodontic appliances
- Framing of orthodontics as a dental specialty by organizing the world’s first educational program to train orthodontists
Categories of Orthodontics Malocclusions
Orthodontic malocclusions are classified based on the position of the molar teeth and the relationship of the jaw bones. They can start in utero even before your baby is born.
There are three basic classifications of malocclusions:
- The mesiobuccal cusp of the maxillary first molar occluding in line with the buccal groove of the mandibular first molar i.e. the maxillary first molar is slightly posteriorly positioned relative to the mandibular first molar.
Class 1 Molars
This most commonly causes a retrognathic facial profile.
The mesiobuccal cusp of the maxillary first molar occluding anterior to the buccal groove of the mandibular first molar i.e. the maxillary first molar, is inline with or anteriorly positioned relative to the mandibular first molar.
Class 2 Molars
The Class 2 molar relationship can be divided into 2 further parts:
- Class 2 Division 1 – Class 2 molars with normally inclined or proclined maxillary central incisors
- Class 2 Division 2 – Class 2 molars with retroclined maxillary central incisors
Class 2 Div 1
This causes a prognathic facial profile. A Class 3 molar relationship is described as:
- The mesiobuccal cusp of the maxillary first molar occluding posterior to the buccal groove of the mandibular first molar i.e., the maxillary first molar, is severely posteriorly positioned relative to the mandibular first molar.
Our mouths often just don’t have the space to accommodate all of our pearly whites—dental crowding is reportedly the most common reason for orthodontic referral malocclusion (a poor alignment of the teeth), which affects one in five people.
What is airway orthodontic?
Airway-focused orthodontics is a philosophy that exceeds everything in contemporary orthodontics. It focuses on clinical orthodontics aimed at achieving ideal jaw growth and development by establishing normal oral function and performance, with optimal contact of not only the teeth but also the tongue position.
Airway-focused orthodontics studies the established link between optimal breathing and long-term health benefits. Certain oral habits and breathing obstructions can force the body to compensate, causing lower oxygen levels in the brain and body.
When I was a teenager, the theory was to wait until all the baby teeth were gone, remove four premolars to make room for all the teeth, then put on braces. Extraction versus non-extraction became a big controversy. My generation that had teeth removed has jaw and breathing issues now that we are older. Many people in their 50s wear a CPAP machine to sleep better and get more oxygen.
“Airway orthodontics” attests to an overall lack of understanding of the bigger picture of a patient’s health. It’s like arguing over which comes first: the chicken or the egg.
Drs. Barry Raphael, Mark A. Cruz, Richard D. Roblee, and Ellen Crean-Binion discuss how airway problems affect structure, function, and behavior and lead to unintended consequences.
The duality around airways is whether the problem is:
1) obstructive sleep apnea — a condition that causes momentary and repeated cessation of breathing throughout the night, or
2) airway flow limitation leads to sleep fragmentation, in which narrowing of the airway anywhere from the tip of the nose to the bottom of the throat makes it harder to breathe day or night.
Nobel-winning biochemist Albert Szent-Gyorgi said, “Science is built on the premise that nature answers intelligent questions intelligently; so if no answer exists, there must be something wrong with the question.”
So let’s take a look at the question surrounding airway orthodontics and how changing our approach may lead us to some useful guidelines.
Many orthodontic thought leaders, including the American Association of Orthodontists, frame the question of the airway in terms of teeth and malocclusion. They ask: Does sleep apnea cause malocclusion? Does malocclusion cause sleep apnea? Can orthodontics cause or cure sleep apnea?
Reframing the question
The question does not directly involve the teeth or malocclusion at all. The question involves breathing and only breathing.
What is a healthy, functioning airway? And what’s not?
Breathing, as we all know, is imperative. Moment to moment, it is the most important thing we do since it feeds every cell in our body with the oxygen it needs and helps to regulate blood pH, which controls the delivery of oxygen to the cells.
I learned with my cancer journey disease in the body happens when there is a highly acidic environment in the body. Breathing is key.
Optimal breathing is done through the nose, where the air is filtered before entering the lungs, powered by the diaphragm to fill the entire lung with little effort and at just the right rate, volume and temperature to get just what the body needs. Breathing should be easy, silent, and through the nose most of the time. These optimal behaviors have developed through evolution to allow us to survive.
If our breathing suddenly stops, we can’t go for more than a few seconds before our brains enter survival mode and activate the sympathetic nervous system. The hypothalamic-pituitary-adrenal (HPA) axis is extremely sensitive to blood oxygenation and will react immediately to protect the body in any way possible if breathing stops.
Behaviors that are adopted by the body to protect or restore oxygen levels are necessary for our survival. If someone blocks your nose and mouth, for instance, you will immediately go into fight/flight/fix mode to change that condition. The same thing happens at night if the airway narrows. The response is immediate and sometimes extreme. In obstructive sleep apnea, there is a delayed response to this threat (hence the cessation of breathing), but eventually, the body will arouse itself and continue breathing if it is to survive. When we mouth breathe at night, we are in a state of flight or fight all night, never getting the rest to need to heal.
It is important to note that chronic threats to breathing require persistent, chronic behaviors to mitigate oxygen levels over time. These suboptimal behaviors are called compensations, and they successfully overcome the chronic threat.
Our bodies are incredible, and they compensate all on their own. We are unaware it is even happening.
When compensations need to be used habitually, they have side effects — unintended consequences — that become chronic problems themselves. It is important to look at both the compensations and their consequences in order to frame our questions about the airway properly.
Compensations and consequences
Both compensations and consequences can be characterized in three domains: structure, function, and behavior.
Here is a brief description of how each relates to breathing.
Structure refers to the anatomy of the airway — specifically its size, shape, and contours. Ideally, air should flow from the tip of the nose to the bottom of the throat in an easy flow pattern. Even around the nasal turbinates that “turbulent” the air to spin particulate matter into the mucous for filtering, the air should flow easily.
Where there is a narrowing of the airway, the air will swirl and become turbulent. This creates a negative pressure that pulls on the sides of the airway, making it even more narrow. If the tissue is resilient, it might flutter (i.e., snoring), but if it is not, it might close up.
In either case, it takes more physical effort to pull air through the narrow spot.
(Try breathing through a drinking straw to feel it.)
During the day, this leads to fatigue. During the night, it leads to fragmented sleep with arousal. Turbulence makes it all the more effortful to breathe and triggers compensations.
Structural malformations that cause turbulence include:
- collapsed or narrow nostrils
- a deviated nasal septum
- a narrow nasal aperture (as part of a narrow maxilla)
- a constricted pharynx (as a result of a deficient maxilla and/or retrognathic mandible)
These anatomic distortions are primary risk factors for airway flow limitation.
Function refers to the physiology of the airway. Any soft tissue enlargement that narrows the airway with swelling, mucous, adipose tissue, and inflammation leads to more turbulence.
Allergies and food sensitivities, frequent colds and infections, swollen lymph tissue, fat deposits at the base of the tongue, swollen mucosa around the turbinates, polyps, cysts, and tumors get in the way. Acid from reflux irritates the throat, nose, and sinuses, making them swell. Narrow airways can lead to eustachian tube stenosis, conductive hearing loss, recurrent otitis media, and dysfunction. Obstructions are risk factors.
Behavior is the most overlooked and misunderstood component of airway dysfunction.
Airway-focused orthodontists realize that compensations and behaviors are at the root cause of breathing dysfunctions and, therefore, must be considered when trying to establish a long-term cure. Leaving compensations at play means leaving their consequences at play, including treatment instability. Dysfunctional breathing and poor tongue posture and function are risk factors for airway flow limitation.
Common examples of compensations at night include mouth breathing, faster breathing, a faster-resting heart rate, short bursts of very rapid heart rate, heavy breathing, forward head posture, stomach sleeping, tossing and turning, frequent awakenings, nightmares, getting up to pee and more. Any time the lips are apart, or any time you can hear breathing — snoring or not — that person is in airway distress.
The unintended consequence of airway dysfunction is a distortion of the shape of the face that worsens airway function.
Poor airway function can lead to chronic intermittent hypoxia that can affect any and all systems of the body. In children, it can damage the growing brain, interfere with sleep, and aggravate neurocognitive and behavioral development.
In adults, it can lead to comorbidities in any system of the body, along with pain and dysfunction. It is a vicious cycle of compensation and consequence that must be interrupted if a patient is to have their distress relieved.
Another unintended consequence of poor skeletal form is malocclusion. Teeth cannot fit into a container that is misshapen. The symptom of malocclusion is completely independent of the symptom of airflow limitation.
This is why I became a myofunctional therapist. It is with the collaboration we can change this process, have better outcomes with braces, sleep, breathe better and live longer, healthier lives.
The role of the airway orthodontist is to break the cycle
All orthodontists are familiar with the term “adenoid faces.” It is a condition that has been described in the literature for over a hundred years and has been researched extensively. We know that this phenotype produces a particular dental malocclusion — the high-angle open bite — that is particularly difficult to correct. This phenotype did not exist in our ancestors.
The adenoid face is not the only phenotype that occurs with airway dysfunction. Various compensations can lead to a variety of phenotypes, including open bites, deep bites, vertical excess, and the full range of angle classifications.?
To solve this dilemma, we must revise yet another concept that orthodontists have been polarizing about since the profession began: nature vs. nurture.
While there are genetic influences on facial shape, the modern study of epigenetics only describes how genes are expressed based on their interaction with the environment.
We cannot control genetics, but we can control the environmental input to the genes. The role of the orthodontist must focus on optimizing facial growth by changing the inputs that influence it.
By reducing the need for compensation and by guiding the behaviors that stimulate growth, we can change the way the entire face grows. Another way of saying the same thing is that there are no genes that code for crooked teeth or dental crowding.
The teeth are just innocent bystanders of a form/function/behavior cycle. The way teeth settle into place is just an unintended consequence of the way the jaws take form; the way the jaws take form is an unintended consequence of poor function, and poor function is most often a consequence of a struggle to breathe easily from very early on in life. Malocclusion is just a symptom of this process.
Interrupting the form/function/behavior cycle is the most important thing an orthodontist can do for people’s health, no matter their age or stage of dental development, but the earlier the problem or trend is recognized and treated, the better.
When the American Dental Association says that we must help children “develop an optimal physiologic airway and breathing pattern,” we have to lessen constriction of the airway anatomy, mitigate harmful physiological challenges, and teach appropriate behaviors for optimal wellness not only when we treat malocclusion, but throughout life. This is how the cycle is broken and redirected toward health.
Creating a beautiful smile and a pretty yearbook picture has its value, but it can no longer be a justification for ignoring other matters. Good structure can be beautiful, but straight teeth in a deficient structure is itself a compensation and prone to relapse over time. Focusing on optimizing the airway gives the orthodontist a better foundation for a beautiful smile and optimal facial balance beyond the dental component/teeth.
Seeing the problem
Once we learn to see the compensations and consequences of poor breathing, we never look at a growing face in quite the same way. Instead of seeing a child’s face as a static phenotype, we now see the dynamic process a child is going through. We don’t just see what a child is but what they are becoming and will continue to become if nothing is done.
The tools for assessment focus not on the teeth but on anything that causes turbulence in the airway.
Dr. Kevin Boyd is one of my favorite mentors, and he has made a tremendous impact in caring for the 0-6 age group. He is creating teams to be better prepared to screen, diagnose and treat the younger children.
Preventative Care for Kids
Proper rest oral posture = tongue mobility that can fit the roof of the mouth, teeth lightly together, and breathing through the nose with lips lightly together is the key to balanced facial growth. If that can be established early, children’s faces will grow favorably forward rather than having long faces, with teeth that are relatively straight and airways that are more open.
Facial Growth Guidance
You cannot adequately treat airway problems without correcting the behaviors that caused them. This is a painful reality for mechanically-minded orthodontists who think perfection lies in our hands, with wires and/ or aligners. Nonetheless, it is imperative to give our kids an optimal physiologic airway and breathing pattern.
We must expand our thinking to include structure, function, and behavior. Our efforts must include interdisciplinary collaboration with many practitioners in the wellness and medical communities as well.
Drs Kevin Boyd and Janet Pannaralla have been inspired by pioneers in this area, such as Drs. William Hang, John Mew, Barry Raphael, Mark Cruz, Jeff Rouse, Marianna Evans, and others have bigger ideas. Every dentist who treats children’s airways doesn’t have to be an orthodontist – or a pediatric dentist. Knowledge is everything; there are anxiety-behavior management and treatment skills that need to be learned.
Most children in Western Societies tend to have their faces grow more vertically (unfavorably) than ideal due to mouth breathing and improper tongue position. Narrow palates and recessed jaws make nasal breathing with the tongue to the roof of the mouth, lips, and teeth lightly together difficult.
Airway orthodontics and Myofunctional therapy are treating children when you have a chance to allow them to grow without the compromise of a poor airway are life-changing – for the kiddos, for the parents, and for our next generation.
Now that you know about airway orthodontics and myofunctional therapy, let’s start asking better questions.
Next week we will get into the question of Can Braces Open the Airway?