Tongue thrusting describes a pattern where the tongue pushes forward against or between the front teeth during activities such as swallowing, speaking, or when the mouth is at rest. This behavior, sometimes referred to as an immature or reverse swallow, is common in infants as a reflex to facilitate nursing or bottle-feeding. However, if it continues beyond early childhood, it can become a concern.
A typical swallowing pattern involves the tongue pressing against the roof of the mouth, specifically behind the upper front teeth, with lips closed and teeth lightly together. In contrast, with tongue thrusting, the tongue protrudes forward, often visible between the teeth, and can involve the lower lip and chin muscles contracting during the swallow. This pushing action can occur during speech, particularly affecting sounds like ‘s’ and ‘z’, or even when the mouth is at rest, with the tongue often resting low and forward.
Underlying Causes of Tongue Thrusting
Tongue thrusting often stems from multiple factors. Prolonged oral habits, such as extended thumb or finger sucking, pacifier use, or prolonged bottle feeding, significantly contribute. These habits can influence mouth and jaw shape, encouraging a forward tongue posture.
Anatomical considerations also play a role. Enlarged tonsils or adenoids may obstruct the airway, leading to chronic mouth breathing, which in turn encourages the tongue to rest in a lower, more forward position to allow for easier airflow. Additionally, a condition called ankyloglossia, commonly known as “tongue-tie,” where the band of tissue under the tongue is shorter than usual, can restrict proper tongue movement and lead to a compensatory forward thrust.
Environmental factors, such as chronic allergies or nasal congestion, can similarly contribute to mouth breathing and a forward tongue posture. Genetics can also play a part; a family history of specific oral and facial structures can predispose individuals to a forward tongue position. Early tooth loss or unusual tooth eruption patterns can create spaces that the tongue naturally fills, thus reinforcing a thrusting habit.
Impact on Oral and Facial Health
The persistent pressure from the tongue against the teeth can lead to various dental issues. A common consequence is an open bite, where the upper and lower front teeth do not meet when the mouth is closed, creating a gap. This constant force can also cause teeth to shift out of alignment, leading to spacing between teeth or the flaring of upper front teeth.
Tongue thrusting can also affect speech patterns. Individuals may develop a lisp, particularly with sounds like ‘s’ and ‘z’, as the tongue protrudes during pronunciation. Difficulty with other sounds such as ‘t’, ‘d’, ‘n’, and ‘l’ can also occur due to altered tongue placement, affecting clear communication.
Beyond dental and speech concerns, prolonged tongue thrusting can influence facial development. It can contribute to a longer, narrower facial appearance due to consistent mouth-open posture. The upper jaw might also appear underdeveloped, further exacerbating dental misalignment. Chewing and swallowing can become less efficient, sometimes resulting in messy eating.
Addressing Tongue Thrusting
Identifying tongue thrusting typically involves an evaluation by dental professionals, such as a dentist or orthodontist, or a speech-language pathologist. These specialists observe the tongue’s position during rest, speech, and swallowing, and examine the teeth for signs of misalignment. They may also inquire about past habits like thumb sucking.
Intervention often centers on myofunctional therapy, involving exercises to retrain the tongue and facial muscles for proper resting position and swallowing. Orthodontic appliances, such as palatal expanders or tongue cribs, may be used with therapy to guide the tongue and correct dental issues.
Addressing underlying medical causes is also important. If enlarged tonsils or adenoids are contributing to mouth breathing, a tonsillectomy or adenoidectomy might be recommended. For those with allergies, managing symptoms can help promote nasal breathing. Speech therapy is often incorporated to correct speech sound errors developed due to tongue thrust. It is advisable to consult a professional if the habit persists beyond early childhood, especially if dental or speech concerns are present.