Tongue thrust refers to a forward or downward resting posture, where the tongue rests against or over the lower teeth.
Tongue thrust can develop the habit of mouth breathing and is usually associated with other conditions such as habitual digit-sucking and open bite malocclusion.
Tongue exercise to increase tongue muscles tone and correct for tongue posture is essential for the treatment of tongue thrust and the associated conditions (Eur J Orthod. 2016; 38(3); 227).