Tongue Thrust in Children: Signs, Causes, Speech Effects, and Treatment
Tongue thrust is the tongue pushing forward between the teeth, at rest or when swallowing. It belongs to a group of orofacial myofunctional disorders (OMDs) and is linked with an interdental lisp, open-mouth posture, mouth breathing, and long-term thumb or pacifier sucking. Treatment usually starts with the airway.
What tongue thrust is
ASHA defines orofacial myofunctional disorders (OMDs) as movement patterns of the mouth and face muscles that result in incorrect tongue positioning at rest and during swallowing, breathing, and speech. Tongue thrusting — the tongue protruding between the teeth — is the best-known sign and may affect both swallowing and articulation.1
How common it is depends on the definition: ASHA cites estimates of tongue thrust swallow in school-aged children ranging from 5.4% to 62.3%, and notes that children with speech sound disorders are more likely to show it.1
Signs of an orofacial myofunctional disorder
| Area | What you might notice |
|---|---|
| Rest posture | Habitual open mouth with lips apart; tongue resting forward or between the teeth |
| Speech | Distorted S and Z, often an interdental lisp; tongue against the teeth for t, d, l, n, ch, j, sh, zh |
| Swallowing | Tongue thrust during swallows; no consistent seal of the tongue against the palate |
| Structure | Tongue-tie; bite differences such as open bite or excessive overjet |
| Other | Drooling past age 4; sleep-disordered breathing; teeth grinding |
Signs of OMDs (ASHA Practice Portal).1
Free Lisp Test
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What contributes to it
ASHA says a single cause is unknown and describes the causes as multifactorial. Factors that may coexist include:1
- Obstructed nasal breathing — enlarged tonsils or adenoids, swollen nasal tissue, or allergies — leading to mouth breathing and an open-mouth posture.
- Chronic nonnutritive sucking or chewing habits (thumb, finger, pacifier, objects) past age 3; prolonged sucking is also a risk factor for malocclusion.
- Structural or muscular differences that encourage tongue fronting, such as delayed neuromotor development, early loss of the upper front teeth, or tongue-tie.
ASHA also cites chronic mouth breathing in 10.1% to 15.9% of children, and one study in which about 31% of children with chronic mouth breathing had a speech sound disorder.1
How it is treated
- 1Clear the airway first: an ENT, allergist, or orthodontist rules out or treats obstructions; closed-mouth posture cannot be set up until breathing is easy.
- 2Orofacial myofunctional therapy then works on closed-mouth resting posture, tongue position, and swallowing.
- 3Speech work follows, since a habitual resting pattern can keep interfering with traditional speech therapy until it is addressed.
This sequence follows ASHA’s Practice Portal, which notes that therapy is usually provided in private practice, clinics, or hospitals rather than public schools, may not be appropriate for children under 4 or who cannot self-monitor, and that diagnosing malocclusion is outside the SLP’s scope — the dental team handles that. ASHA also cautions that punitive habit appliances have shown limited success.1,2
About SpeechStep
SpeechStep is speech-sound practice for ages 4–8 and does not treat orofacial myofunctional disorders. Its lisp check is a quick screen, not a diagnosis.
Frequently asked questions
What is tongue thrust?＋
ASHA describes tongue thrusting as protrusion of the tongue between the teeth, which may affect swallowing and articulation. It is one sign of orofacial myofunctional disorders — movement patterns of the mouth and face muscles that lead to incorrect tongue positioning at rest and during swallowing, breathing, and speech.
Does tongue thrust cause a lisp?＋
They often go together. ASHA lists distorted /s/ and /z/, often with an interdental lisp, among the signs of OMDs, and notes that children with speech sound disorders are more likely to show a tongue thrust swallow.
What causes tongue thrust?＋
There is no single known cause. ASHA lists factors that may play a role: obstructed nasal breathing (enlarged tonsils or adenoids, allergies), chronic nonnutritive sucking or chewing habits past age 3, and structural differences such as tongue-tie or early loss of upper front teeth.
How is tongue thrust treated?＋
Through orofacial myofunctional therapy, usually after any airway problem is addressed by an ENT, allergist, or orthodontist. ASHA notes it is usually provided in private practice, clinics, or hospitals rather than public schools, and may not suit children under 4 or those who cannot yet self-monitor.
Put this into practice today
Try the free lisp test, or start daily AI speech practice — every child takes one SpeechStep at a time.
References
2 sources from authoritative bodies. Last reviewed October 2026.
- 1.ASHAOrofacial Myofunctional Disorders — Practice Portal page.
- 2.ASHAOrofacial Myofunctional Disorders — Consumer page.