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Winchester, VA 22601
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The Importance of Nasal Breathing

Dr. Gio Iuculano, DDS

In this interview, Dr. Gio Iuculano of Winchester Dental explains how and why nasal breathing is best for overall health; the health consequences, evaluation, and treatment of mouth breathing; and why it’s important to identify it early.

Why is nasal breathing important? Can you give us a general overview of its role in helping the body to function?
Nasal breathing is critical to overall well-being. It plays a role in TMJ dysfunction, sleep apnea, and orthodontics. Our bodies are designed for us to generally keep our lips together and teeth apart, breathing through our noses. The importance of air going through the nose is multifold. When air goes through the nose, the nose filters out harmful bacteria and particles that we don’t want in our lungs; it humidifies the air so that when it reaches the lungs, it’s at the proper temperature, which better allows the exchange of oxygen; and it produces nitric oxide in the nose. Nitric oxide is critical for heart health and blood vessels.

When an individual doesn’t breathe nasally, it places him or her at a significant detriment. From a sleep apnea standpoint, if we’re making a patient a mandibular advancement device to open their airway at night; or if we’re making them a DNA device to enlarge the airway, the nose breathing is critical. Sometimes we need to retrain patients who breathe mainly through their mouths, and we tend to refer those cases to oral myofunctional therapists (OMTs). An OMT’s job is to work with the tongue, but they also look at breathing. We have lots of patients who work with OMTs to learn exercises and techniques to retrain the brain to close the mouth, close the lips, and then properly breathe through the nose. For many patients with sleep apnea appliances, we see a huge improvement of the efficacy of the appliances once we establish their nasal breathing. For example, nasal breathing also helps with blood pressure, and that’s a key reason why once we correct a patient’s sleep apnea and breathing, the patient’s blood pressure goes way down, and frequently patients don’t have to take blood pressure medications anymore as there is no need for it.

Herbst Mandibular Advancement Device


DNA Appliance


From a TMJ standpoint, if a patient can’t breathe through his or her nose, the only other possibility is through the mouth. That creates mouth breathing, which itself has several detrimental effects on the body. One of the critical parts of mouth breathing is that it drops the tongue and causes the mandible to posture down and forward. That puts a strain on the jaw joint and all the muscles, which can contribute to headaches, sleep apnea, TMJ pain, facial pain, and other issues.

Nasal breathing is also important from an orthodontic standpoint. When we evaluate children for orthodontics, we are looking at the jaw position, the jaw joints, the nasal passages, and the airway in the back of the throat. When a child mouth breathes, just like an adult, it forces that mandible down and forward. When left untreated—if the child’s mouth is constantly positioned down and forward—it is almost like putting in an orthodontic appliance that causes the face or the head of a growing child to grow long and skinny, instead of round. If the child develops a long and skinny face for these reasons, it causes constriction of the nose, nasal passages, and the back of the throat, and creates a breathing disorder. Frequently we can catch a child in the mouth breathing stage, correct the breathing, expand the palate, and restore proper facial growth. That is the advantage to screening children early. It’s preferable to evaluate children at five years old for all facial growth aspects. We can do it in older children and adults, but it’s always harder.

Your colleague Victor D. Woodlief, DMD corroborates this. He has said that children who breathe primarily through their mouths will develop long faces, allergies, and obstructions in their nasal passages, thus changing their development.
Correct. Many children who are mouth-breathers will also be higher risk for strep throat and enlarged tonsils and adenoids. We see a lot of children whose mouth breathing we can correct early enough. We convert them from mouth breathing to nasal breathing, their nasal passages open up when used, their adenoids shrink and their tonsils shrink. Many times we can avoid tonsil and adenoid removal surgery.

Are they at higher risk for strep throat and enlarged tonsils and adenoids because the mouth breathing agitates their throats?
Yes. When you mouth breathe, your body is ingesting air through your mouth, it doesn’t get filtered or humidified, and it’s a bigger volume of air than through the nose. The body starts to adapt to this different volume of air and different concentration of oxygen. That causes a lot of changes in the body’s systems; a classic one is that it changes the pH level in the blood. When you are not nasal breathing, your blood pH becomes more acidic, increasing your predisposition to cancer because your body is more acidic, and cancer cells grow more easily in an acidic environment.

Going back to how nasal breathing affects the whole body, you mentioned that nasal breathing filters the air and that helps convert the oxygen to help the heart. How?
Breathing through the nose, you produce nitric oxide, which is actually a hormone, and that helps regulate a lot of the cardiovascular systems. It helps the heart, it helps dilate blood vessels, and allows blood flow to reach all body parts more easily.

If mouth breathers are going to have heart issues, will that show up only in adulthood, or do children have heart issues because of mouth breathing?
There may or may not be studies on this issue. I can say that if you start mouth breathing in your teens or younger, you start to build a deficiency of nitric oxide. Over time your body has an adaptive capacity—it can take things that aren’t working properly and adjust. Those who are mouth breathing start at such a young age that lacking nitric oxide, eventually they reach their adaptive capacity limit. That may be why we see heart disease earlier in life—strokes and heart attacks earlier in life, in 40-year-olds. That may also be why we see people who don’t fit the classic “look” of someone with heart disease. Sometimes 40-year-old individuals in fairly good shape have heart attacks. We believe a lack of nitric oxide resulting from mouth breathing is a contributing factor to that—not the only one, but a contributing factor. It’s important to remember, however, that the body is too complex to single out one thing as the cause of one problem. The more ideally the body works, though, the better off someone will be long-term.

When children come in for evaluation, how can you tell if they are mouth breathers?
Great question! Many times during our clinical exams, when we’re evaluating children for orthodontics for phase one or phase two—which ever it may be—we observe them while they are in the treatment chair. I look to see if their lips are apart or closed. When a child’s lips are generally positioned apart, it probably indicates he or she is mouth breathing, because if not, there wouldn’t be a reason for the lips to be apart. If the jaw is too far back, that makes it harder for the lips to seal, and that can contribute to the mouth breathing. Our patient forms include a question that asks, “Have you noticed your child mouth breathing?” If I think a child might be mouth breathing, I’ll let the parents know, and I’ll ask them to pop into the child’s room to observe from time to time over the next few days while the child is asleep. We also ask if the child snores. Children should never snore; if a child is snoring, it is a sign of a sleep breathing disorder. Adults can snore and not have sleep apnea, but kids who snore have sleep breathing disorders, according to the American Academy of Pediatrics. All pediatricians should be asking their patients’ parents when they come in each time if their children snore.

Why is it that adults can snore and be okay, and children can’t?
It has to do with the volume and the size of the airway. It’s bigger in adults, who can get that snoring turbulence and still manage to get air through.

What are the indicators that you’ve been successful in treating mouth breathing in affected children?
When we take an initial set of x-rays of children during an orthodontic evaluation, we can see the airway, the nasal passages, the tonsils, and adenoids. We find that in children who are mouth breathing, their jaws are starting to get the long and narrow look, and are angled very steeply. We do the phase one orthodontics, expand the palate, and correct the breathing. When we take new x-rays two years later, we see that the jaw steepness levels out. This indicates that the children’s faces are now growing rounder and properly.

Can you summarize the importance of nasal breathing?
If you are nasal breathing and not mouth breathing, you will have a better chance of not needing orthodontics as a child. If you’re breathing nasally you will have less risk of TMJ issues; and we tend to see that if you breathe nasally at night when you sleep, your incidence of sleep apnea is much less, or not as severe. Overall, we find that promoting proper breathing is critical to all the phases of treatment that we provide at Winchester Dental.