Could myofunctional therapy help you? Our ten-question self-assessment takes under a minute, and nothing you check is sent anywhere.
You brush twice a day, two minutes at a time. You breathe for the other 23 hours and 56 minutes. If you spend those hours with your lips apart and your tongue low in your mouth, brushing can’t keep up.
Nobody comes in for mouth breathing. They come in for teeth that shifted after braces, a sore jaw, gums that bleed in one spot, or a child who snores. Mouth breathing is often underneath those problems, and it rarely gets named.
How mouth breathing causes cavities
Air moving across your front teeth all night dries them out, right when saliva has slowed to almost nothing. Saliva neutralizes acid, clears food and puts minerals back into enamel. Take it away for eight hours and those teeth have no protection during the longest stretch of the day.
It isn’t the breathing that causes the decay. It’s the drying, at the worst possible time.
Quick answers: Can mouth breathing cause cavities? and Why are my lips always chapped, even with Chapstick?
What it does
- Decay on the upper front teeth. The effect with the clearest explanation, described above.
- Red, puffy gums across the upper front teeth only. Inflammation that stops where the airflow stops is close to a signature finding.
- A dry mouth. Trouble swallowing dry food, a sore throat in the morning, and more decay everywhere. Dry mouth has its own article.
- Bad breath that brushing doesn’t fix. Less saliva means less clearing of the bacteria behind it.
- Snoring, poor sleep and daytime tiredness. Strongly linked, and a question for a physician first. What a dentist can and can’t do about it.
- Teeth that won’t stay put. A low tongue pressing forward pushes on the teeth for hours a day, which is why relapse after braces and mouth breathing so often go together.
- Chapped lips and cracked corners. Minor, but a reliable clue.
- In a growing child, a narrower upper jaw. A tongue resting on the palate pushes the upper arch outward. A low tongue doesn’t, and the result can be a high, narrow palate and crowded teeth.
These aren’t equally proven. The drying is basic physiology. The sleep links are well documented but belong to sleep medicine. The effect on a child’s jaw is accepted but hard to measure in any one child. In an adult, a narrow palate won’t change, but it tells us the pattern has been there a long time.
Signs we look for
No single sign is a diagnosis. Several together are worth acting on.
- Gum inflammation on the upper front teeth only, with the rest of the mouth healthy.
- Scalloped edges on the tongue, from pressing against the teeth instead of resting on the palate.
- Lips apart at rest, often with chapped lips or cracked corners.
- A narrow, high palate.
- Waking with a dry mouth or sore throat, snoring, restless sleep or daytime sleepiness.
Check yourself
Notice these right now, before you adjust anything. The first answer is the one that counts.
- Your lips are touching, without effort
- Your teeth are slightly apart
- Your tongue is up against the roof of your mouth, broad and flat
- You’re breathing through your nose
If any of those took effort, that’s the finding. It’s a habit, and habits can be retrained.
Why it doesn’t fix itself
Usually something blocked the nose first: allergies, a deviated septum, swollen turbinates, or in children, enlarged tonsils and adenoids. Las Vegas’s dry, dusty air doesn’t help. Switching to the mouth is the body doing the sensible thing, not a lack of willpower.
The catch is that once the nose is fixed, many people keep breathing through their mouth anyway. By then it’s a habit, not a necessity.
Fixing the nose and retraining the habit are two separate jobs. Doing only the first is why so many people still mouth breathe years later.
What we measure
We hold a wooden depressor between your lips, teeth apart, and you breathe normally through your nose for three minutes while we time it.
We record the seconds, not just a pass or fail, so going from 40 seconds in January to two minutes in March shows up. How the test ends matters too. Lips giving out means muscle weakness, the most trainable finding. Opening up for air points to the nose. The tongue pushing the stick out is a different problem again.
The therapy
Myofunctional therapy is physical therapy for the tongue, lips and swallow: daily exercises that rebuild strength and change a resting position you’ve held for years, with no appliance, no surgery and nothing to wear. Dr. Lee-Mirzayan is certified in it.
If a tongue tie keeps the tongue from reaching the palate, that’s treated first, because no amount of practice gets a tethered tongue up there. Read about tongue-tie release.
What the research shows
There are no trials on cavities. The link runs through dry mouth, which is well established. We recommend therapy when the mechanism fits, not as a proven cavity treatment.
The best research is on sleep apnea, and it’s mixed. Reviews agree it helps snoring, daytime sleepiness and sleep quality. On the apnea index itself, the two most recent analyses found about the same effect, nine to ten fewer events an hour, but only one called it significant. One also found a clear improvement once people practiced more than 30 minutes a day. Both reviews are on our sleep apnea page.
About half of people respond strongly and the rest barely change. The only way to know which you are is to measure.
Repairing the damage
Retraining stops the cause but doesn’t rebuild what’s lost. Front teeth that dried out for years are often worn thin, decayed at the gum line, or both. They may need bonding, or a crown if too little tooth is left. We’d rather do that once the breathing is addressed, so the repair doesn’t fail for the same reason the tooth did.
Where to start
A daily saline nose rinse, a nasal strip like Breathe Right at night, and year-round allergy treatment cost almost nothing, and a nose that works comes first. Beyond that, it depends on the cause, which is what an exam is for. Read more about myofunctional therapy, or tell us what’s going on.