Mouth Breathing and Jaw Pain: Is There a Connection?
If you've searched for the cause of jaw pain or TMJ dysfunction, you've probably come across claims that mouth breathing is to blame.
The truth is more nuanced.
Mouth breathing doesn't automatically cause temporomandibular disorders (TMD), and many people who breathe through their mouth never develop jaw pain. However, growing evidence suggests that persistent mouth breathing may influence how the jaw, tongue, neck, and airway work together, particularly when it becomes a long-term habit or results from an untreated airway problem. Rather than being the cause, it may be one contributing factor.
Why Does It Matter?
Our bodies are designed to breathe through the nose whenever possible.
Nasal breathing naturally encourages the lips to stay closed, the tongue to rest against the roof of the mouth, and the jaw to remain in a relaxed position.
When breathing shifts to the mouth, that resting position often changes. The tongue sits lower, the lips separate, and the jaw hangs slightly open to maintain airflow. Research has shown that changing the breathing route alters tongue pressure and the activity of muscles beneath the jaw.
In children, persistent mouth breathing has been associated with changes in facial growth and dental development. In adults, the effects are more likely to be functional, affecting muscle coordination, jaw posture, and loading of the temporomandibular joint.
This doesn't mean mouth breathing causes TMD, but in someone who already has jaw sensitivity, poor sleep, or increased muscle tension, it may become one of several contributing factors.
It's Rarely Just About the Jaw
One of the biggest misconceptions is that mouth breathing is simply a bad habit.
Often, it's the body's way of adapting to another problem, such as:
Chronic nasal congestion or allergies
A deviated nasal septum
Enlarged tonsils or adenoids
Chronic sinus problems
Sleep-disordered breathing
A learned breathing pattern that persists after the original problem improves
If someone cannot breathe comfortably through their nose, telling them to "just breathe through your nose" isn't realistic—or helpful.
How Do We Assess It?
There isn't a single test for mouth breathing, so we look at the whole picture.
Common questions include:
Do you wake with a dry mouth?
Do you snore or feel unrefreshed?
Can you comfortably breathe through your nose at rest?
Do you have frequent nasal congestion?
Do you clench or grind your teeth?
Is your jaw sore in the morning?
Depending on the findings, assessment may involve an ENT physician, dentist or orthodontist, sleep physician, or orofacial myofunctional therapist.
What About Mouth Taping?
Mouth taping has gained popularity online, but the evidence is still limited.
Some small studies suggest it may help carefully selected people with mild obstructive sleep apnea who can already breathe comfortably through their nose. However, current research does not support mouth taping as a routine treatment for mouth breathing or TMD.
More importantly, mouth taping doesn't address why someone is breathing through their mouth.
If nasal breathing is blocked by allergies, a deviated septum, or another airway issue, forcing the mouth closed may make breathing more difficult. Before considering mouth taping, it's important to determine whether nasal breathing is actually comfortable and appropriate.
What Does Treatment Look Like?
Treatment depends on the underlying cause and may include:
Managing allergies or chronic nasal congestion
Referral to an ENT or sleep physician when airway or sleep concerns are suspected
Dental or orthodontic assessment when bite or jaw development is involved
Orofacial myofunctional therapy to improve tongue posture, swallowing, and breathing patterns
Physiotherapy to address jaw function, muscle sensitivity, neck mechanics, posture, and breathing coordination
The goal isn't simply to close the mouth—it's to restore comfortable, efficient breathing while improving the function of the entire jaw-neck-airway system.
The Bottom Line
Persistent mouth breathing is unlikely to be the sole cause of TMD, but it may influence jaw posture, muscle activity, tongue position, sleep quality, and overall function.
Rather than searching for one single cause, the most effective approach is to consider how the airway, breathing, sleep, jaw, neck, and nervous system interact. By identifying and treating the underlying reason for mouth breathing, we can often support healthier jaw function and better long-term outcomes.
References
Lin, L., Zhao, T., Qin, D., Hua, F., & He, H. (2022). The impact of mouth breathing on dentofacial development: A concise review. Frontiers in Public Health, 10, 929165. https://doi.org/10.3389/fpubh.2022.929165
Milanesi, J. M., Berwig, L. C., Marquezan, M., Schuch, L. H., de Moraes, A. B., da Silva, A. M. T., & Corrêa, E. C. R. (2018). Variables associated with mouth breathing diagnosis in children based on a multidisciplinary assessment. CoDAS, 30(4), e20170071. https://doi.org/10.1590/2317-1782/20182017071
Rhee, J., Iansavitchene, A., Mannala, S., Graham, M. E., & Rotenberg, B. (2025). Breaking social media fads and uncovering the safety and efficacy of mouth taping in patients with mouth breathing, sleep-disordered breathing, or obstructive sleep apnea: A systematic review. PLOS ONE, 20(5), e0323643. https://doi.org/10.1371/journal.pone.0323643
Takahashi, S., Ono, T., Ishiwata, Y., & Kuroda, T. (2002). Breathing modes, body positions, and suprahyoid muscle activity. Journal of Orthodontics, 29(4), 307–313. https://doi.org/10.1093/ortho/29.4.307
