Chewing training can increase bite force in some studies. This does not prove that it creates a more defined jaw. Chewing-gum data do not automatically validate silicone exercisers sold to change the face.
Strength, muscle and facial shape: three different outcomes
A 2024 randomised trial in 58 adults studied six months of gum-chewing training. Bite force increased, but no significant change in masseter thickness or mandibular shape was observed.
A strength gain must therefore not be rewritten as a promise of aesthetic definition. Findings also depend on what was measured: biting harder in a test, having a thicker muscle and liking one's face are different outcomes.
Read the population and equipment used in each study before connecting it to a product. The word “jaw” in a scientific title does not justify every accompanying claim.
What do we know about silicone exercisers?
Research collected in the MyoForce evidence file did not identify a relevant trial demonstrating an aesthetic effect from silicone exercisers marketed to the public. This limitation also applies to facial transformation claims used for similar appliances.
Research exists using a medical device in older people, including a 2020 trial on bite force and muscle thickness. That population and functional goal do not support promising a more defined jaw to a young adult.
Do not confuse a chewing object, rehabilitation prescribed after assessment and a device intended to protect teeth. They address different questions.
Harder and longer: progression without aesthetic evidence
A small trial of very hard gum observed greater fatigue and pain during effort. It does not establish that all chewing causes a disorder, but contradicts the idea that substantial discomfort is necessary for benefit.
Observations concerning oral habits and temporomandibular disorders also require caution. The OPPERA cohort finds an association between reported parafunctions and onset of disorders; it does not calculate the risk of a particular exerciser.
If pain, locking or a change in how the teeth close occurs, stop trying the device and seek advice. Do not add resistance to push past discomfort.
Why this guide does not offer seven universal exercises
A useful programme begins with a goal: recovering a function, improving an identified ability or treating an examined difficulty. A repetition count taken from a study does not become a prescription for everyone.
If a professional prescribes exercises, have the movement demonstrated and ask about stopping criteria, frequency and review timing. If your goal is purely aesthetic, first ask what is actually demonstrated before buying an accessory or starting a routine.
MyoJaw, mewing and tongue retraining: understanding the differences
MyoJaw appears in the catalogue as an unavailable jaw exerciser. MyoForce attributes neither a demonstrated facial-shape result nor a pain-treatment role to it.
The mewing is covered in a separate guide: its aesthetic claims are not established. Tongue retraining with a functional goal discussed with a professional is different again.
The Myoforce appliance belongs to this latter category. It should not be used to force the jaw or replace pain assessment. For night-time grinding, instead see the role of a bruxism guard.
Common questions
Does chewing gum define the jaw?
The cited trial finds increased strength without a significant mandibular-shape change. It does not support promising an aesthetic result.
Must it hurt to work?
No. Pain is not a training goal. Significant or persistent discomfort warrants stopping and seeking advice.
Can an exerciser be used for bruxism?
The presented data do not establish this use. Troublesome clenching or grinding requires assessment and discussion of management.
Sources and review
Guide reviewed on 1 October 2026 by Dr Vladimir Khourda. The references below concern the topics studied; they do not establish the results of a MyoForce product.