The mouth opening exercise is a slow, controlled jaw movement done sitting up. You relax your face, open your mouth slowly as wide as stays comfortable, hold for a few seconds, then close it slowly. Physios and dentists sometimes include jaw opening like this in home programs for a stiff or sore jaw (temporomandibular disorder, or TMD). Your tongue stays relaxed, so the mouth can open wider than in the version with the tongue held on the roof of the mouth.

How to do the mouth opening exercise

Sit upright on a chair with your feet flat and your hands resting on your thighs. Let your shoulders, face and jaw go loose.
If your jaw feels tight, the voice guide suggests first rubbing the muscles along your jawline and cheeks gently with your fingertips for a few moments.
Open your mouth slowly and evenly, as wide as is comfortable, stopping before any pain. Let the jaw drop straight down rather than sliding to one side.
Hold the open position for a few seconds while you breathe easily.
Close your mouth slowly until your lips meet, with your teeth resting just apart rather than pressed together.

What you should feel

A gentle stretch in front of your ears and in the cheeks as the mouth opens wide, and light work under the chin. There should be no pain, catching or locking.

Common mistakes

Opening fast, or forcing the last bit of the opening.
Letting the jaw swing to one side as it opens.
Snapping the mouth shut or clenching your teeth at the end.
Tensing the neck and shoulders, or tipping the head back to open wider.

How often

A common starting point is 5 to 10 openings, holding each for 3 to 5 seconds, 2 or 3 times a day. Your physio will adjust this.

Stop and check with your physio if

Pain in your jaw, face or ear that builds with each opening, or your jaw starts to catch, click painfully or lock so it will not open fully. Stop. If it stays stuck, or the pain stops you eating or drinking, get medical advice the same day from your doctor or dentist.
Your mouth gets stuck open and will not close, or your jaw feels out of place and your teeth no longer meet as they did. Go to an emergency department straight away, supporting your jaw gently with your hand, and do not drive yourself. Call emergency services if you also find it hard to breathe.
Things look double, your vision suddenly blurs or goes, your speech slurs or becomes muddled, swallowing becomes hard, your face or lips go numb, one side of your face droops or one side of your body goes weak or numb, you suddenly become so dizzy or unsteady that you fall or cannot stand or walk, your legs suddenly give way but you do not black out (a drop attack), or you get a sudden severe headache. Stop and call emergency services, even if it goes away.
Jaw, neck, shoulder or arm pain that comes with chest pain or tightness, sweating, feeling sick, feeling light-headed or being short of breath, or that comes on when you exert yourself, feel stressed or go out in the cold and does not ease within a few minutes of rest. Call emergency services straight away, as this can be a heart attack. If it eases quickly with rest and none of these happen, get medical advice the same day, and do not exercise again until you have been checked.

From the clinic

The video shows a wide but calm opening with the hands resting on the thighs. It does not show the jaw massage the voice guide mentions, so treat that part as optional. The voice guide also says to bring your teeth back together at the end. NHS advice for a sore jaw is to keep your teeth apart except when you are eating, so the steps finish with your lips closed and your teeth resting apart.

Open only as far as feels comfortable, even if that is not very wide at first. If your jaw is sore or clicks, start with the smaller movement of jaw opening with the tongue on the roof of the mouth and ask your physio when to try this wider version. An occasional click with no pain is common. A click that hurts, or a jaw that catches, is your cue to stop and tell your physio.

If your jaw has ever got stuck open, check with your dentist or physio before you start, because opening wide, as in a big yawn, can bring it on again. After jaw surgery or a broken jaw, check with your surgeon before you start, and follow their plan. New, frequent headaches with pain or tenderness at your temples or on your scalp, or, if you are 50 or over, new jaw aching that comes on as you chew or talk and eases when you stop, need medical advice the same day, as they can be signs of inflamed arteries in the head (giant cell arteritis). If your vision changes, call emergency services.

The TMJ disorder program covers the self-care that comes first, such as soft food and resting the jaw, and where jaw exercises fit.

Written and checked by the PocketPhysio editorial team. Last updated 2026-09-28.

This page is general education, not a diagnosis or a personal treatment plan. If you have pain, an injury or a health condition, see a physiotherapist or doctor before starting new exercises.

Mouth opening exercise