How do I measure my own opening?

Stack your index, middle and ring fingers vertically and try to place them between your upper and lower front teeth. Three fingers is roughly normal. Two or fewer, especially with pain, is worth having examined.

Will stretching my jaw open help?

It depends entirely on why it is limited, which is why this is not a good thing to guess at. Controlled range work helps some presentations and aggravates others — forcing a joint-restricted jaw can worsen the inflammation causing the restriction.

Limited Jaw Opening

Normal jaw opening is roughly 40–55mm between the front teeth, or about three of your own fingers stacked vertically. Consistently less than that, particularly with pain or a hard end point, is worth investigating — and the quality of the restriction tells a clinician nearly as much as the measurement.

Muscle restriction feels different from joint restriction

A muscle-limited jaw usually has a soft end feel: with gentle pressure it will open a little further, and the limitation varies through the day and improves with heat. A joint-limited jaw has a hard end feel — it stops, and no amount of gentle pressure moves it. That distinction is one of the most useful pieces of information from a physical examination, and it points at completely different treatment.

Which way the jaw deviates matters

A jaw restricted by a joint problem tends to deviate toward the affected side as it opens, because the healthy side keeps translating while the restricted side cannot. A jaw restricted by muscle more often deviates and then corrects. Watching the path of opening in a mirror is something you can usefully observe yourself before an appointment.

Less common causes worth excluding

Not every limited opening is TMD. Infection, a recent wisdom tooth extraction, trauma, prolonged immobilisation, certain medications, and rarely tumours or systemic conditions can all restrict opening. A limitation that appeared suddenly without a jaw-related trigger, or that comes with fever, swelling or numbness, needs prompt medical assessment rather than a TMJ appointment.

Common questions

How do I measure my own opening?: Stack your index, middle and ring fingers vertically and try to place them between your upper and lower front teeth. Three fingers is roughly normal. Two or fewer, especially with pain, is worth having examined.
Will stretching my jaw open help?: It depends entirely on why it is limited, which is why this is not a good thing to guess at. Controlled range work helps some presentations and aggravates others — forcing a joint-restricted jaw can worsen the inflammation causing the restriction.

Not sure where to start?

Request a virtual consultation with Dr. Samadian. In-person visits are by appointment in New York.

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