Tongue thrust (also called reverse swallow or immature swallow) is the common name of orofacial muscular imbalance, a human behavioral pattern in which the tongue actively protrudes through the anterior incisors during swallowing and speech due to a neuromuscular imbalance. This is what is considered by most professionals as a true tongue thrust.
When the tongue passively protrudes between the anterior teeth while the tongue is at rest (as in the case of an overly–large tongue), this is a postural phenomenon, or a pseudo-thrust.
Doctors treating patients with large anterior spacing and extreme proclination should consider the size of the tongue or the tongue thrusting habit prior to commencing treatment.
Some factors that can contribute to tongue thrusting include:
- A neuromuscular imbalance
- An enlarged tongue
- Thumb sucking
- Large tonsils
- Hereditary factors
When considering the correction for an anterior openbite, it is imperative to determine the actual etiology, i.e. is it an environmental result of a large tongue, or a result of a hyperactive tongue thrusting against those teeth?
Proper identification and correction of an anterior openbite problem will greatly increase the long–term success of the treatment and the stability of the retention. While referral to a speech therapist may help with a neuromuscular imbalance, correction of the environment or openbite to allow the large tongue to properly occupy the oral cavity without it applying excessive labial pressure against the teeth can be sufficient without the help of a therapist.
Possible correction of an openbite can include clear aligners, ‘reverse-curve’ archwires, vertical elastics, or orthognathic surgery, depending upon the severity of the problem. A long-term retention protocol may be advised to increase stability of the correction.
(Photo credit: Pacific West Dental Group)