A reverse swallow, also known as tongue thrust, is an oral motor pattern where the tongue pushes forward during swallowing, often pressing against or between the front teeth, or even protruding between the lips. This dysfunctional movement can occur during swallowing, speaking, or at rest. While normal in infants, its persistence beyond early childhood can indicate an underlying issue.
Understanding the Mechanics of Swallowing
Normal swallowing involves a coordinated action where the tongue plays a specific role. During a mature swallow, the tip of the tongue rests against the roof of the mouth, just behind the upper front teeth, creating a seal. The lips remain closed, and the teeth lightly touch as the tongue pushes food or liquid backward towards the throat. This action generates pressure that facilitates movement of substances down the esophagus without exerting undue force on the teeth.
In contrast, a reverse swallow deviates from this efficient process. The tongue moves forward or sideways, pushing against the teeth or positioning itself between the dental arches. This often occurs with noticeable contraction of the lower lip and chin muscles. This forward movement prevents the tongue from achieving the proper seal against the palate, altering swallowing mechanics and impacting oral structures.
Factors Contributing to Reverse Swallowing
Several factors contribute to a reverse swallow. Prolonged oral habits, such as thumb or pacifier sucking beyond an appropriate age, are frequently linked to this condition. These habits can influence palate and jaw development, creating space that encourages the tongue to rest and thrust forward.
Chronic nasal congestion from allergies or enlarged tonsils and adenoids can also play a role. Difficult nasal breathing often leads to mouth breathing, causing the jaw and tongue to position lower and more forward for airflow. This altered resting posture can translate into a forward thrust during swallowing. Genetic predispositions, an unusually large tongue, or a short lingual frenum (tongue-tie) can also influence tongue positioning and contribute to a reverse swallow.
How Reverse Swallowing Affects Health
The consistent pressure from a reverse swallow can lead to health implications, particularly concerning oral development. A person swallows between 1,200 to 2,000 times daily, with each swallow generating 1 to 6 pounds of pressure. This continuous force can push teeth out of alignment, causing dental issues like an open bite, where upper and lower front teeth do not meet. It can also lead to front teeth protrusion.
Beyond dental alignment, a reverse swallow can affect speech patterns. Individuals might develop a frontal lisp, where the tongue protrudes against or between the teeth when producing sounds like /s/, /z/, /sh/, /ch/, and /j/. This can result in distorted speech. The pattern can also contribute to mouth breathing, associated with snoring and sleep-disordered breathing. Abnormal tongue and jaw positioning can also lead to jaw discomfort and tension headaches.
Addressing Reverse Swallowing
Addressing a reverse swallow typically involves retraining oral and facial muscles through myofunctional therapy. This specialized program uses targeted exercises to strengthen the tongue, jaw, and facial muscles, aiming to establish proper tongue posture and swallowing techniques. These exercises help the tongue learn to rest on the palate and engage correctly during swallowing, reducing forward thrust.
Early intervention is beneficial, helping prevent or minimize long-term effects on dental alignment and speech development. Consulting with healthcare professionals like dentists, orthodontists, and speech-language pathologists is important for a comprehensive evaluation and treatment plan. These specialists can work together to address the muscular habit and any resulting dental or speech concerns. Identifying and addressing underlying causes like chronic nasal congestion or enlarged tonsils may also be part of the treatment strategy.