Orofacial myology is the study and treatment of the muscles in and around the mouth, face, and throat, specifically how they function during breathing, swallowing, chewing, and speaking. When these muscles develop abnormal patterns, whether from habit, structural issues, or developmental factors, the resulting problems are called orofacial myofunctional disorders (OMDs). The therapy side of this field uses targeted exercises to retrain those muscle patterns and restore healthy function.
What Orofacial Myofunctional Disorders Look Like
OMDs cover a range of symptoms that might seem unrelated at first glance but share a common root: the muscles of the face, tongue, and jaw aren’t working the way they should. The most recognizable signs include a habitual open-mouth, lips-apart resting posture, tongue thrusting (where the tongue pushes forward between the teeth during swallowing), and abnormal tongue resting position. Instead of resting against the roof of the mouth, the tongue may sit low, press forward against the front teeth, or push sideways against the back teeth.
These muscle patterns ripple outward into other functions. Speech is a common casualty: many people with OMDs develop a lisp or distort sounds like “s,” “z,” “t,” “d,” and “l” because the tongue isn’t landing where it should during articulation. Drooling past the age of four, difficulty chewing solid foods, trouble transitioning to cup or straw drinking, and teeth grinding are all part of the picture. In some cases, OMDs are also linked to sleep-disordered breathing and obstructive sleep apnea.
Structural issues can both cause and result from these disorders. A restricted lingual frenulum (tongue-tie) limits the tongue’s range of motion, which can set off a chain reaction of compensatory muscle patterns. Dental misalignment, including open bites, overbites, and crossbites, frequently shows up alongside OMDs.
How Muscle Patterns Shape Facial Growth
In children, the stakes are particularly high because the bones of the face and jaw are still growing. The tongue, lips, and cheeks exert constant low-grade pressure on developing bone, and the direction of that pressure matters. When a child breathes comfortably through the nose with lips gently closed and the tongue resting against the palate, those forces guide the face toward balanced, forward growth. When the pattern breaks down, the growth trajectory changes.
Chronic mouth breathing is one of the clearest examples. Children who habitually breathe through the mouth tend to develop a longer, narrower face with an increased lower facial height, a steep jaw angle, and a narrow upper dental arch. Clinicians sometimes call this the “adenoid face” because of its association with enlarged adenoids that block nasal airflow. The upper lip becomes less functional, the chin drops back, and the lower front teeth can tilt inward.
Tongue thrust swallowing creates its own set of problems. Instead of pressing upward against the hard palate during a swallow, the tongue pushes forward or sideways into the teeth. Over thousands of swallows per day, that force can separate the front teeth into an open bite or push the back teeth out of alignment into a crossbite. A short frenulum compounds the issue by physically preventing the tongue from reaching the palate, restricting both bone growth and airway size. Because posterior crossbites don’t self-correct as teeth develop, early intervention gives children the best chance of normal jaw growth and clear speech.
What Therapy Involves
Orofacial myofunctional therapy is a structured, exercise-based program. It’s not a quick fix. A typical treatment plan involves a minimum of 20 sessions, each lasting about 30 minutes. Sessions usually start weekly, then space out to every two weeks, then monthly as the patient progresses. The first 10 sessions focus heavily on learning correct tongue posture, since that resting position is the foundation for everything else.
The exercises themselves target specific muscle groups and functions. Some strengthen lip seal, others train the tongue to rest and swallow correctly, and some address nasal breathing patterns. For children, compliance matters, so therapists often use exercises that feel more like play. Balloon blowing, for instance, is a common exercise with high compliance rates: the child takes a deep breath through the nose and exhales into a balloon, repeating three times a day. It strengthens the lip muscles, reinforces nasal breathing, and gives kids something tangible to do.
The goal isn’t just conscious performance of the exercises. The real milestone is when the correct patterns become subconscious. After enough practice sessions, therapists introduce reminder cues, like signs or boards placed around the home, that prompt the child to check their tongue position or lip seal throughout the day. Sessions continue until the new patterns are fully ingrained.
Impact on Sleep Apnea
One of the most compelling applications of myofunctional therapy is in sleep apnea treatment. The muscles of the tongue and throat play a direct role in keeping the airway open during sleep. When those muscles are weak or poorly coordinated, the airway is more likely to collapse.
A systematic review and meta-analysis found that myofunctional therapy reduced the severity of obstructive sleep apnea by roughly 50% in adults and 62% in children, as measured by the apnea-hypopnea index (a standard measure of how many times breathing stops or becomes shallow per hour of sleep). In the adult studies, the average score dropped from about 24.5 events per hour to 12.3 after at least three months of therapy. In one pediatric study, it dropped from nearly 5 events per hour to under 2.
Perhaps more striking is the long-term data. A study tracking children who had their tonsils and adenoids removed (plus palatal expansion) found that the 11 children who continued myofunctional therapy exercises remained essentially cured of sleep apnea four years later, with an average of just 0.5 events per hour. The 13 children who didn’t do the exercises saw their sleep apnea return, climbing back to 5.3 events per hour. The exercises appear to maintain the muscle tone and coordination needed to keep the airway stable during sleep.
The Tongue-Breathing Connection
Research on tongue pressure helps explain why resting tongue position matters so much. During nasal breathing, the tongue sits against the palate with relatively low pressure. Switch to mouth breathing, and tongue pressure increases significantly in both upright and lying-down positions. The tongue’s main muscle shows its peak activity during inhalation, while tongue pressure against the palate peaks during exhalation, creating a rhythmic cycle tied to each breath.
When someone becomes a habitual mouth breather, this changes the forces acting on the teeth and palate around the clock. The tongue drops away from the roof of the mouth, removing the outward pressure that helps the upper jaw grow wide. Meanwhile, the cheek muscles, now unopposed, compress the dental arch inward. Over months and years, the result is a narrow palate, crowded teeth, and a face that grows downward rather than forward. Myofunctional therapy works to reverse this by retraining nasal breathing and restoring the tongue to its proper resting position against the palate.
Relationship With Orthodontics
Orthodontists have long recognized that braces can straighten teeth, but if the underlying muscle dysfunction isn’t addressed, the teeth tend to drift back. This is especially true for open bites, where the front teeth don’t meet when the jaw is closed. If a tongue thrust swallow continues after braces come off, the tongue keeps pushing the teeth apart.
Research supports combining the two approaches. One retrospective study found that myofunctional therapy paired with orthodontic treatment was more effective than orthodontics alone at preventing open bite relapse. In another study, 90.3% of children achieved proper lip seal after therapy that included lip massage and tongue training, and open bites shrank by an average of 2.1 millimeters over 12 months. A systematic review found that myofunctional therapy carried a lower relative risk of open bite relapse compared to surgical approaches and both fixed and removable dental appliances, though the authors noted the evidence base is still limited.
The takeaway is practical: if you or your child is getting orthodontic treatment for an open bite or other malocclusion linked to tongue or lip dysfunction, myofunctional therapy before, during, or after braces can help protect that investment by addressing the muscle habits that caused the problem in the first place.
Who Provides This Therapy
Orofacial myofunctional therapy is delivered by trained professionals, most commonly speech-language pathologists, though some dental hygienists and other clinicians pursue specialized certification. The International Association of Orofacial Myology (IAOM) is the primary professional organization in the field. Because OMDs overlap with dental, orthodontic, ENT, and sleep medicine concerns, treatment often involves a team. Speech-language pathologists handle the muscle retraining but don’t diagnose dental malocclusions or jaw joint disorders. Those assessments come from dentists, orthodontists, or oral surgeons working alongside the myofunctional therapist.