Most people are born with the genetic potential to grow jaws that are big enough to accomodate all their teeth.
When the muscles of the mouth and face develop improper resting postures and functional patterns, growth and development will deviate away from that potential and orthodontic problems start developing.
Since form follows function, the idea behind myofunctional therapy is to Identify and replacing these abnormal muscle patterns with more normal activity. In a growing child, this sets the stage for a more normal pattern of orofacial growth and development to occur.
The younger a child is treated, the quicker the results and the greater the potential there is of avoiding serious orthodontic problems from developing. Early treatment also improves the chance of achieving optimal facial balance and airway development. The only lower limit to age is how well a child can understand the goals and co-operate with treatment.
Proper orofacial muscle balance is the key to favourable growth and development.
This video demonstrates the importance of proper resting muscle postures for normal dental and facial development.
When the tongue is in the correct position in the roof of the mouth, the resultant force can stimulate forward growth of the upper jaw and the teeth will move into a rounded, well-developed arch form.
Common causes of abnormal muscle balance and improper development include
1. Obstructed nasal breathing
Obstructed nasal breathing is one of the most common causes of improper facial and dental development in modern populations.
The resultant mouth breathing results in an open mouth posture. The lower jaw is dropped lower, the tongue is pulled away from it’s proper resting spot up against the front of the roof of the mouth. Read more about mouth breathing here.
2. Thumb and finger sucking
Thumb or finger sucking lowers tongue posture and generates constricting forces on jaws from the cheeks during sucking. The thumb places pressure on the roof of the mouth which pushes up the palate, and also forces which tip the teeth. The open mouth posture changes the direction of growth of the lower jaw.
3. Bottle feeding and pacifiers
Breastfeeding promotes tongue to palate contact and requires “suckling” that stimulates the jaw muscle activity that promote forward growth of the jaws. Bottle feeding and pacifiers cause a lowered tongue position and use “sucking” which requires less effort and does not stimulate the same growth. They cause improper tongue position and result in forces of the lips and cheeks that constrict the jaws.
4. Tongue ties
A tongue tie is a anomaly which presents as a short, thick piece of skin (known as the lingual frenum) that connects the underside of the tongue to the floor of the mouth. It may decrease mobility of the tongue tip. It occurs in 5% of people and is a factor in breastfeeding problems and inability of a baby to attach.
5. Tongue thrusts or reverse swallow
Tongue thrusting is the habit of placing the tongue in the wrong position during swallowing, either too far forward our out to the sides. It is estimated that there is an average of 1,200-2000 swallows per day. The constant pressure of the tongue on the teeth forces the teeth and jaws out of alignment.
These improper swallowing patterns can develop as a result of bottle feeding, sucking habits or mouth breathing.
Goals of therapy
In contrast to traditional orthodontics where the focus is on straight teeth for aesthetics, myofunctional therapy is aimed at changing the activity of the muscles to alter jaw and dental development. It increases the chances of accomodating all teeth in the jaws without extractions to relieve crowding, but does not rule out that braces will be required altogether.
The specific outcomes to be achieved include
breathing through the nose
lips together at rest
correct tongue position
no overactivity of the lower lip muscles when swallowing
a more stable environment for any future orthodontic treatment
What does therapy involve?
Once the muscle factors that are contributing to abnormal development are identified, a treatment plan to achieve more normal activity is developed.
This may involve one of any combination of the following
Referral to an Ear Nose and Throat (ENT) Specialist
A plan of action to eliminate habits such as pacifier, thumb or finger sucking
Orofacial Myology or repatterning of the muscles through simple exercises
Myofunctional training appliances that promote good muscle balance, good lip seal, nasal breathing and correct position of the tongue in the roof of the mouth.
When is the best time to start treatment?
Th best time to benefit from an early myofunctional evalation is as soon as possible. It is simpler to reverse abnormal patterns of muscle activity as early as possible.
Treating children with baby teeth can be relatively quick, simple. and non-invasive The longer delay in addressing abnormal muscle activity, the more severe orthodontic problems become and the greater the need for corrective treatment including braces, extractions to relieve crowding or even jaw surgery in the future.