What is it?
In a jaw dislocation the condyle of the lower jaw moves past the bony ridge in front of it and cannot come back. Your mouth stays open, your front teeth do not meet, speaking and swallowing become difficult and saliva collects. There may be pain at the point of the chin and a feeling of a hollow in front of the ear.
It most often starts at a moment when the mouth is opened very wide: yawning, laughing, being sick, a long procedure inside the mouth, an endoscopy or procedures during a general anaesthetic can all be listed. A blow taken while the mouth is open can lead to the same thing. In some people this happens again and again.
What separates a jaw dislocation from locking caused by the disc is the direction: with a dislocation your mouth will not close, while with disc-related locking it will not open. This distinction makes it easier both for you to describe what has happened and for the right approach to be chosen.
Signs
You will not necessarily have all of these at once.
Why does it happen?
- 01
Opening the mouth very wide
During a yawn, a burst of laughter, singing or biting into a large mouthful, the condyle can move past the ridge in front of it. If you have had a similar episode before, the same movements can set it off again.
- 02
Long procedures and interventions
Dental treatment with the mouth held open for a long time, endoscopy, securing the airway during a general anaesthetic and bouts of being sick are commonly reported triggers. When the muscles tire, the joint is less well protected.
- 03
Joint laxity and the shape of the socket
Dislocation develops more easily in people whose ligaments are lax from birth and in joints where the socket is shallow. In some conditions that affect connective tissue, the tendency to recur is marked.
- 04
Medicines and neurological causes
Involuntary muscle contractions linked to certain anti-sickness and psychiatric medicines, and the contractions that occur during a seizure, can lock the jaw forwards. If that happens, reviewing the medicine is a decision for the doctor who prescribed it.
How does it progress?
- Extent
Dislocation on one or both sides
In a dislocation on both sides the mouth stays wide open and the jaw juts forwards. In a one-sided dislocation the point of the chin shifts to the opposite side; this appearance can be confused with a fracture.
- Acute
A first, recently developed dislocation
In a dislocation dealt with within hours the muscles have not yet tightened fully, so putting the jaw back is most often easier.
- Recurrent
A dislocation that keeps coming back
It recurs even with an ordinary yawn. Beyond putting the jaw back, a plan is needed to reduce how often it happens.
- Chronic
A dislocation left out of place for a long time
Once days and weeks have passed the surrounding tissues stiffen; simple help by hand may not be enough, and more involved methods come into play.
How is it treated?
What needs to be done is to put the jaw back into place, and this is done by a clinician experienced in it. If there is a history of a blow, imaging is used first to rule out a fracture. Local anaesthetic or medication may be needed to relax the muscles; that decision belongs to the clinician. Trying it yourself, or having someone close to you force it, can injure teeth and soft tissue.
Once the jaw is back in place you will be asked to protect it for a while: a supporting bandage, avoiding opening your mouth wide, a soft diet and supporting your chin with your hand when you yawn are all advised. The follow-up examination in this period is there to assess the state of the joint and the muscles.
With recurrent dislocations, putting the jaw back is not enough on its own; approaches ranging from injections around the joint to surgical options are assessed in oral and maxillofacial surgery. In dislocations that have been left out of place for a long time, the procedure may be carried out in hospital and under sedation.
- Your mouth not closing, and this having gone on for hours
- The jaw staying open after a blow, with numbness or bleeding alongside it
- Difficulty breathing or swallowing
- The jaw dislocating again shortly after being put back
How is it prevented?
- Put your hand under your chin when you yawn so that your mouth does not open too wide.
- If your jaw has dislocated before, tell your dentist ahead of any long procedure and ask for breaks.
- In the first few weeks avoid large mouthfuls and hard foods that take a long time to chew.
- If a medicine is thought to have caused the dislocation, talk to the doctor who prescribed it before stopping it on your own.
Frequently asked questions
- Can I try to put my jaw back myself?
- You are asked not to. Putting the jaw back is a procedure that needs the hands placed at the right points and the muscles relaxed; forcing it can injure your fingers, break a tooth and damage the tissues around the joint. And because there may be an underlying fracture when the problem follows a blow, an assessment has to come first.
- Does a dislocated jaw get better on its own?
- In some people the jaw settles back into place on its own within a short time, but waiting for that is not the general approach. As time passes the chewing muscles tighten and it becomes harder to bring the condyle back; medication or hospital conditions may be needed for the procedure. That is why a jaw that will not close is dealt with the same day.
- If my jaw has dislocated once, will it dislocate again?
- There is a chance of it recurring, and it is more marked in people whose ligaments are lax. Avoiding opening your mouth wide in the first few weeks, supporting your jaw when you yawn and keeping away from hard foods are all aimed at reducing the risk of it happening again. Where it recurs often, further options are assessed in oral and maxillofacial surgery.
This content is for general information and does not replace an in-person examination. Symptoms overlap between conditions, and a diagnosis can only be made clinically.