Tongue Thrust: Signs, Causes and Treatment

01Definition

What tongue thrust is

ASHA describes tongue thrusting as protrusion of the tongue between the teeth, which may affect swallowing and speech. Its public information page explains that some children have a common type of orofacial myofunctional disorder (OMD) called tongue thrusting or fronting, in which the child pushes the tongue forward when talking, eating or drinking.

OMDs are movement patterns of the mouth and face muscles that lead to incorrect tongue position at rest and during swallowing, breathing and speech. ASHA notes that they can occur at any age and can coexist with speech and swallowing disorders.

02Function

Resting posture, swallowing and speech

ASHA explains that a typical resting posture of the mouth has the lips closed, breathing through the nose, the teeth slightly apart and the tongue tip resting against the front of the hard palate, at the lower front teeth or the gums behind them. A tongue resting forward, or protruding between the front teeth, can interfere with normal tooth eruption and lead to an open bite.

During swallowing, a professional watches for the tongue tip pushing forward or between the teeth. ASHA notes that tongue thrust beyond the age at which this pattern is usually expected to disappear may be a sign of an OMD or another underlying problem, such as difficulty breathing through the nose.

03Signs

Signs in children and adults

ASHA lists signs of orofacial myofunctional disorders, which may include:

• a habitual open-mouth, lips-apart resting posture or mouth breathing
• the tongue resting forward or between the teeth, even when not speaking or eating
• pushing the tongue forward when swallowing, or difficulty closing the lips to swallow
• distorted “s” and “z” sounds, often an interdental lisp, and difficulty with sounds such as “sh” or “j”
• drooling and poor control of food or saliva beyond about 4 years of age
• bite problems such as an open bite, overjet or underbite

ASHA stresses that having one or more of these signs does not mean someone has an OMD, and that some messiness when eating is normal in babies and toddlers. Lips apart at rest is also normal before the lips are fully grown; most people achieve a lips-together resting posture around 12 to 13 years of age.

04Causes

Causes and contributing factors

ASHA explains that no single cause is known and that several factors often coexist:

• a blocked nose due to enlarged tonsils or adenoids, swollen nasal tissues or allergies, which leads to mouth breathing and a forward tongue
• sucking habits, such as thumb, finger or dummy (pacifier) use, continuing beyond about 3 years of age
• differences in mouth structure or muscle development that encourage the tongue forward, including tongue-tie

ASHA notes that research on the effect of tongue-tie on speech and feeding is conflicting; not everyone with a tongue-tie needs a procedure. See our guide to tongue-tie.

05Effects

Effects on teeth and speech

ASHA reports that studies show significant correlations between signs of OMDs, such as tongue thrust swallow, and dental malocclusions and speech sound disorders, and that children with speech sound disorders are more likely to show a tongue thrust swallow. Estimates of tongue thrust in school-aged children vary widely between studies, from about 5% to over 60%, and correlation does not prove causation.

A forward tongue posture can make it harder to place the tongue correctly for some sounds. ASHA notes that, in some cases, an orthodontist may need to treat an open bite before therapy for tongue thrust or an interdental lisp.

06Assessment

Who assesses it

ASHA’s public page explains that several professionals may be involved: a dentist or orthodontist to look at the teeth and jaw, a doctor to check for allergies or enlarged tonsils and adenoids, and a speech-language pathologist to evaluate how the person speaks, eats, drinks and breathes.

The speech-language pathologist takes a detailed history, including sucking habits, breathing, snoring, allergies, dental treatment and feeding, and examines the lips, tongue, jaw, palate and teeth, resting posture, swallowing and speech. ASHA notes that speech-language pathologists do not diagnose medical or dental conditions and refer to the relevant professional when needed.

07Therapy

Myofunctional therapy

ASHA explains that the first step is to address medical issues such as breathing problems or enlarged tonsils. A speech-language pathologist can then help the person become aware of how they move their mouth and face, learn where the tongue and lips should be when speaking, drinking and eating, improve speech sounds, chewing and swallowing, and practise nasal breathing.

The professional plans therapy for each person. ASHA notes that myofunctional therapy may not be suitable for children under about 4 years of age or who cannot yet self-monitor or follow directions.

08Team

Working with the orthodontist

ASHA describes treatment of OMDs as interprofessional. Opening the nasal airway may involve an ENT specialist, an allergist or an orthodontist, while myofunctional therapy addresses tongue and lip posture. A closed-mouth posture cannot be consistently established until airway problems are resolved.

Speech-language pathologists do not diagnose bite problems; they refer to a dentist or orthodontist. Myofunctional therapy does not replace orthodontic treatment, and the decision on appliances or procedures belongs to the dental or medical team.

09Sources

Where the sources differ

ASHA’s public information page (reviewed May 2026) presents tongue thrusting mainly in children and focuses on signs and practical steps. ASHA’s Practice Portal for professionals describes OMDs across the lifespan, including adults, and is more cautious about the evidence: prevalence estimates vary widely, and correlations between tongue thrust, bite problems and speech do not prove that one causes the other.

On habits, ASHA notes that dental habit-breaking appliances have limited success and have been associated with pain and other problems, and that praise and positive reinforcement can help children stop sucking habits. Our speech therapy service in Bilbao assesses tongue thrust in children and adults, in coordination with the dentist or orthodontist; it does not replace orthodontic treatment (consultations are in Spanish).

10Summary

In summary

Tongue thrust is a forward tongue pattern during swallowing, speech or rest, often linked to mouth breathing, sucking habits and mouth structure. It can coexist with bite problems and speech sound errors. Assessment involves doctors, dentists or orthodontists and a speech-language pathologist, and treatment starts with breathing problems before myofunctional therapy.

Questions for the first visit help separate the reason, the findings and the goal. What is the main concern: speech, eating, drooling or a dental finding? Has the nose and breathing been checked? What did the dentist or orthodontist find? Which habits are present? And what measurable goal will therapy aim for, such as lips closed at rest or a clearer “s”?