Conditions / Mouth breathing
Mouth breathing
When the default mode of breathing is through the mouth rather than the nose, the lips often rest apart and the tongue rests low in the mouth. Over time, this affects how the face develops, how the teeth align, and how well you sleep.
Reviewed by Gina Sabbak, RDH · Myofunctional Therapist, Louisville KY. Last reviewed . Educational content — not a substitute for in-person evaluation.
What it is
Nasal breathing is the anatomical default: air is filtered, humidified, and warmed; nitric oxide is produced; the diaphragm works efficiently. Mouth breathing bypasses most of this.
In children, chronic mouth breathing is associated with long-face growth patterns, narrower dental arches, and disrupted sleep. In adults, it is associated with snoring, fragmented sleep, dry mouth, and increased dental decay risk.
Nasal breathing is the body's anatomical default. When the lips rest apart and the tongue rests low, we lose the architectural support that shapes how the face grows.
Common signs
- Lips apart at rest
- Dry mouth on waking
- Snoring or noisy sleep
- Frequent nasal congestion
- Forward head posture
- Bedwetting in older children (when paired with other signs)
How myofunctional therapy may help
Educational, not diagnostic. Outcomes vary; results are not guaranteed.
Restore nasal breathing as the default through lip-seal training, tongue-up posture, and breathing exercises.
Coordinate with your allergist, ENT, or dentist when the cause is structural (e.g., enlarged tonsils, deviated septum).
What to expect
A 60-minute evaluation identifies the cause (habit, structural, or both).
A typical program runs 4–6 months for adults and 6–9 months for children.
Lip-seal and daytime nasal-breathing cues often shift in the first 2–3 weeks.
Keep learning
Related reading
- Mouth breathing in children: why it matters
Educational article (~5 min read).
- Breathing Retraining
How this service supports this condition.
- All conditions we work with
The full set of myofunctional patterns we support.
- How we may help
Overview of the assessment and program structure.
Common questions about mouth breathing
- What is mouth breathing and why does it matter?
- Mouth breathing is a pattern where the default route of breathing during rest, sleep, or activity is through the mouth instead of the nose rather than through it. Nasal breathing filters, humidifies, and warms incoming air and supports healthy diaphragm movement. Mouth breathing bypasses much of this. Over time, chronic mouth breathing can affect how the face and dental arches develop in children, and is associated with dry mouth, snoring, and disrupted sleep in adults.
- Is mouth breathing harmful in children?
- Persistent mouth breathing in children has been associated with long-face growth patterns, narrower dental arches, and disrupted sleep. It often shows up alongside other signs: lips apart at rest, snoring, frequent nasal congestion, and restless sleep. Because much of facial growth happens in the early years, addressing the habit early — including any structural cause such as enlarged tonsils or a deviated septum, which an ENT or allergist would evaluate — gives the most flexibility.
- Can adults develop mouth-breathing patterns?
- Yes. Adults can develop or worsen a mouth-breathing pattern from chronic nasal congestion, allergies, structural changes, or habit. Many adults come in after years of snoring, dry mouth on waking, or a recent dental concern. The good news is that the muscle and habit components respond well to therapy at any age, even when some structural cause remains.
- How can myofunctional therapy help with mouth breathing?
- Myofunctional therapy addresses the muscle and habit side. We work on lip seal, tongue-up resting posture against the palate, and nasal-breathing cues during the day and at night. When a structural cause is part of the picture — enlarged tonsils, deviated septum, allergies — we coordinate with your allergist, ENT, or dentist. This work is part of our Breathing Retraining service (/services#breathing-retraining).
- How long does it take to correct mouth breathing?
- Programs vary based on the underlying cause and the patient's age. For adults with a habit-driven pattern, therapy typically runs 4–6 months. For children, programs often run 6–9 months because we are also working with active facial growth. Lip-seal and daytime nasal-breathing cues often shift within the first 2–3 weeks of consistent home practice.
Open references
Where the illustrations come from
The anatomical illustrations on this page are drawn from openly licensed educational sources. We attribute them in the caption; the canonical sources are linked here for anyone who wants to verify or use them.