A jaw that will not open, or will not close, is frightening in a way most dental problems are not. It happens suddenly, it interferes with eating and speaking, and the instinct is to force it — which is usually the worst available option.
This article covers the two kinds of locking, what to do in the first hours, what to avoid, and when the situation needs same-day attention. If your jaw is locked right now, start with the section that matches your situation.
The Two Kinds of Lock
They sound similar and are nearly opposite.
Closed lock — the jaw will not open fully. Maximum opening is typically restricted to somewhere between about 20 and 30 millimeters, roughly one to two fingers’ width instead of the normal three. There is often a hard, abrupt end-feel, as though something is physically blocking further opening, and the jaw frequently deviates toward the affected side as it opens. Many patients report that the joint used to click and then, at some point, the clicking stopped and the restriction began.
That history is the classic presentation of disc displacement without reduction. The articular disc, which normally sits between the condyle and the skull base and translates forward with it, has displaced anteriorly and is no longer recapturing. The condyle runs into it rather than gliding under it. The disappearance of a long-standing click is not improvement — it is often the moment the disc stopped reducing.
Open lock — the jaw is stuck open and will not close. This usually follows a wide opening: a yawn, a long dental appointment, a bite into something tall, occasionally vomiting. The condyle has translated forward past the articular eminence and the muscles have gone into spasm behind it, preventing it from sliding back. This is a subluxation or frank dislocation, and it is the more acute of the two.
If Your Jaw Is Stuck Open
This one needs prompt professional attention. Call our office, and if you cannot be seen promptly, go to an urgent care or emergency department.
While you arrange that:
• Stay as calm as you can. Anxiety increases muscle spasm, and spasm is what is holding the joint out of position.
• Apply moist heat along the sides of the face over the jaw muscles.
• Support the jaw gently with your hand. Do not push.
• Do not try to force it closed, and do not let someone without training attempt a reduction. Reduction requires a specific technique and specific hand positioning, and an untrained attempt risks injuring the joint further or the person attempting it.
The longer a dislocation stays unreduced, the more the muscles spasm and the harder reduction becomes. Hours matter here. A joint that has dislocated once is also more likely to do it again, so once the acute episode is resolved, the joint instability behind it is worth evaluating.
If Your Jaw Will Not Open Fully
A closed lock is uncomfortable and limiting but is not usually an emergency. It still deserves evaluation within days rather than weeks, because the sooner a displaced disc is addressed, the better the prospects for restoring motion.
In the meantime:
• Soft diet. Nothing requiring wide opening or forceful chewing. No bagels, steak, large sandwiches, raw apples, or chewing gum.
• Moist heat over the jaw muscles for fifteen to twenty minutes, several times a day. For a joint that is acutely painful and swollen rather than tight, cold may be more comfortable — use whichever genuinely helps.
• Gentle range-of-motion work within the pain-free range. Open slowly to the point of restriction, not through it. Repeated gentle movement maintains what motion you have.
• Over-the-counter anti-inflammatory medication, if appropriate for you, following the label and your physician’s guidance.
• Rest the jaw. Keep the teeth slightly apart at rest, the tongue against the palate, and limit talking where you can.
• Avoid wide opening. Support the chin when you yawn.
What not to do: do not force the jaw open, do not have someone manipulate it, do not persist with aggressive stretching, and do not ignore it for months. Chronic unreduced displacement is associated with adaptive changes in the joint that are harder to address later.
Why Jaws Lock
• Disc displacement, the most common cause of closed lock, often with a history of clicking that stopped
• Joint hypermobility and ligament laxity, which predispose to open lock and recurrent dislocation; generalized hypermobility conditions are frequently in the background
• Prolonged wide opening — long dental appointments, intubation, oral surgery
• Muscle spasm, particularly in the lateral pterygoid, which can restrict motion without any disc problem
• Trauma to the jaw or face
• Degenerative joint disease, where arthritic change alters the joint surfaces
• Chronic heavy clenching, which stresses the ligaments over years — and which, in a substantial number of patients, traces back to disturbed breathing during sleep
Related reading: Why Does My Jaw Click and Pop? A Dentist Explains the 5 Main Causes.
What Evaluation Should Include
• A history of onset, prior clicking, trauma, prolonged opening, and previous episodes
• Measured range of motion — maximum opening, right and left lateral excursion, and protrusion — with the restriction pattern noted, since a disc block and a muscular restriction limit motion differently
• Joint palpation, loading, and auscultation
• Muscle palpation, particularly the lateral pterygoid
• Cone beam CT imaging of the condyles and joint spaces; MRI when the disc position itself needs to be visualized, since the disc is soft tissue and does not appear on CT
• Assessment of generalized joint laxity where recurrent dislocation is the pattern
• Sleep and airway screening, because nocturnal clenching is a common contributor to the ligament damage behind both presentations
Treatment
For closed lock, treatment aims to restore motion and reduce the load on the joint: manual techniques to improve translation, a therapeutic orthotic designed to unload the joint and adjusted over a series of visits, trigger point therapy and photobiomodulation for the associated muscle spasm, graded range-of-motion exercises, and anti-inflammatory measures. Many patients regain functional opening with conservative care even when the disc does not return to position, because the joint adapts.
For recurrent open lock, the priority after reduction is stabilizing the joint — regenerative injection therapy to tighten lax capsular ligaments, an appliance to limit excessive translation, behavioral modification around wide opening, and management of the clenching load.
Referral to an oral and maxillofacial surgeon is appropriate for locking that does not respond to conservative care, for significant degenerative change, and for recurrent dislocation that stabilization measures do not control.
When to Seek Care Immediately
• A jaw stuck open that will not close
• Locking after trauma to the face or head
• Severe pain with inability to eat or drink
• Fever, swelling, or signs of infection alongside the restriction
• Numbness, facial weakness, or difficulty swallowing or breathing
Frequently Asked Questions
My jaw unlocked on its own. Do I still need to be seen? Yes. An episode that resolved tells you the mechanism is present, and both closed and open lock tend to recur. Evaluating after it settles is far easier than evaluating mid-episode, and it is the point at which the underlying instability can actually be addressed.
Will I need surgery? Most patients will not. The majority of locking responds to conservative care, and surgery is reserved for cases that do not, or for significant structural change. Anyone whose first recommendation is surgery, before conservative care has been tried, is worth a second opinion.
My jaw used to click and now it doesn’t, but it won’t open as far. Is that better? That combination usually means the opposite of improvement. A click that stops as opening becomes restricted is the characteristic history of a disc that has stopped recapturing. It should be evaluated.
→ Call for a jaw locking evaluation: (408) 516-1432
About Joint & Airway Analytics
Joint & Airway Analytics is a TMJ, airway, and craniofacial pain practice in San Jose, California, founded and directed by Victor D. Woodlief, DMD. The practice focuses on temporomandibular disorders, sleep-disordered breathing, and orofacial pain, and treats patients from San Jose, Campbell, Los Gatos, Saratoga, Cupertino, Santa Clara, Willow Glen, and the wider Bay Area.
Joint & Airway Analytics
385 S. Monroe Street, San Jose, CA 95128
Phone: (408) 516-1432
Website: www.airwayhealth.net