Lock jaw


The symptoms of a blocked jaw include a disruption of the jaw closure. The closing of the jaw can only be impaired or not work at all. The affected person's jaw is then permanently open and regardless of the strength and exertion with which the affected person tries, he or she does not manage to close the jaw. But where does this symptom come from and what is the cause?

Causes of a locked jaw

The causes of a locked jaw are variable and not easy to diagnose. In the majority of cases, the jaw joint is the origin of the problem with closing the jaw. In older patients, it is primarily the TMJ osteoarthritis that can lead to a lock in the jaw. This disease is a disease of wear and tear of the joint that can occur in old age due to the massive period of wear and tear.

A dislocation can also be the reason for the blockage. During the dislocation, the temporomandibular joint head is no longer in the joint pit, but has jumped out of the joint path. Already with excessive mouth opening, for example when yawning, this locking of the jaw can occur through a dislocation. These symptoms are further enhanced by stress and mental illness.

Read more on the topic: Dislocated jaw

Another reason, jaw fractures can be an obstacle to jaw closure, as the broken fragments can unlock the jaw, so that the normal closure of the mouth can only be performed again when the fragments are surgically repositioned. As a rule, the symptoms disappear immediately when the cause of the locked jaw has been treated.

In very rare cases, swelling of the oral mucosa and connective tissue after central anesthesia in the area of ​​the temporomandibular joint can lead to disturbances in the opening and closing of the jaw. The same applies to swelling caused by abscesses in the jaw area.
Read on under: Local anesthesia at the dentist

Locking the jaw after a wisdom tooth operation

A blocked jaw, the inability to close the jaw, is rare after a wisdom tooth operation.
Difficulties are caused by the opposite, the jaw clamp. The mouth opening is disturbed with the jaw clamp. This problem occurs often and especially when removing all wisdom teeth in one session, as the jaw often has to be expanded to the maximum in order to reach the wisdom teeth. As a result of this stretching, the jaw muscles are often cramped and can no longer perform their normal functions.

When anesthetized with the syringe, the puncture into the muscle can be so traumatic that a bruise forms. This hematoma prevents the muscle from stretching and contracting, making it difficult to open the mouth. The external force that the dentist or oral surgeon has to use to pull the teeth out can also temporarily injure one of the masseter muscles.
You might also be interested in: Side effects of local anesthesia

The jaw clamp can persist for several weeks after the procedure. Therapeutically, an attempt is made to gradually expand the mouth with plastic rods stacked on top of one another in order to release this tension or cramping. The patient has to work actively at home to train the targeted stretching piece by piece.

Psychological causes of a locked jaw

Psychological aspects are very closely related to diseases of the temporomandibular joint, and stress can trigger a lock in the jaw in the event of a malfunction of the temporomandibular joint. Stressful everyday life or psychological stress transfer problems in the form of clenching and grinding to the jaw.
Excessive opening of the mouth while yawning would be sufficient to provoke the already stressed temporomandibular joint head jumping out of the joint pit. This dislocation is accompanied by a lock of the jaw.

Mental illnesses such as depression or burn-out syndrome are also associated with temporomandibular joint problems, which can result in blocked jaws. In addition to dental therapy, we recommend psychological therapy in order to sustainably reduce emotional stress. Otherwise, a mental illness can cause repeated jaw problems.

Lock jaw diagnosis

The diagnosis of a blocked jaw is often confused with the symptoms of a clamp, which is why this is not easy to make. In the dental practice, the lock is verified on the basis of its clinical appearance. A detailed general anamnesis is used to determine the cause of the blocked jaw.
X-ray diagnostics or a DVT can also provide information in the event of fractures or temporomandibular joint dislocations and help with the diagnosis.

Accompanying symptoms of locked jaw

In addition to the open mouth, since the jaw lock is impaired by the lock, there are other side effects. The attempt of the person concerned to initiate the jaw closure with force usually causes severe pain. The pain of the muscles is predominant.
Speaking and eating are very difficult because of the open jaw. If the person concerned tries to move, it can cause jaw joint cracking and severe pain.

How do you release a lock jaw?

The symptoms of a locked jaw, the inability to close the jaw, can be alleviated by eliminating the cause.
If the underlying disease is wear and tear, osteoarthritis of the temporomandibular joint, the lock will disappear immediately after an operation.

In the event of a dislocation of the temporomandibular joint head, the treatment of choice is the Hippocrates handle, in which the lower jaw is returned to the joint path. Experienced patients who have already had these symptoms frequently are able to master the Hippocrates handle themselves and can use it. But in principle this should be left to the dentist. After the mandibular joint head has been returned, the lock has also disappeared and the jaw can be closed without any problems.

If jaw fractures are the cause of a lock, the fractures must first be fixed surgically, as they represent a functional obstacle and the misalignment of the bone pieces prevent the jaw from closing. After fixation with titanium screws or plates, the jaw can be closed again immediately after the operation.

Exercises with a lock jaw

The exercises for locking the jaw are relatively limited. The patient himself cannot or can hardly restore the jaw closure by exerting force or the like.

If the jaw lock is caused by the temporomandibular joint head jumping out, it can be released with a special handle, the Hippocrates handle. However, this manipulation can only be carried out properly in an experienced state, which is why the dentist should remove the blockage. The patient is only able to loosen the muscles and relieve tension through circular, lightly powerful massage movements of the hands.

Can you release a lock yourself?

There is one cause, the dislocation, in which the affected person can release the lock himself with a little practice. During the dislocation, the TMJ head has jumped out of the joint pit outside the normal joint path and cannot find its way back on its own. Therefore, the jaw can no longer be closed. I.

In this case there is what is known as the Hippocrates' handle to reverse the dislocation. The affected person moves the lower jaw downwards and forwards with a little pressure, so that the joint head is back in the original joint path. Therapeutically, the dentist would use exactly the same treatment to reposition the joint head.

Nevertheless, it is important to be careful not to pull the lower jaw with too much force in order not to injure it. If you have no experience, you should therefore go to the dentist and avoid doing this yourself in order to avoid negative complications.

Duration of a lock jaw

The duration of a locked jaw is closely related to the treatment of the cause and is usually associated with the success of the therapy.
If, for example, the jaw joint head jumping out is the cause of the jaw lock, the repositioning of the head in the joint pit by the dentist means that the jaw lock also disappears immediately and the jaw can be closed again. The same applies to broken bones. If these are surgically repositioned and fixed, the jaw closure is immediately possible again, as the various causes always act like a functional obstacle.

This allows the duration of an open mouth to vary from a few minutes to a few hours or days, which is why a general answer always depends on the individual case, the severity and the therapy.

Lock and Clamp - What's the Difference?

The lock and clamp are completely opposite. With a jaw clamp, the mouth can no longer be opened; with a lock, the jaw closure is hindered or not possible. In the case of a locked jaw, the causes are usually the jaw joint itself or jaw fractures.

A jaw clamp has much more diverse possible causes, which makes it difficult to determine the localization of the problem. It can result from a harmless bruise on the muscle after numbing it prior to dental treatment, but it can also be caused by changes in the salivary gland or muscle spasms. In both diseases, the symptoms usually disappear very quickly with treatment of the actual cause.

See also under: Jaw clamp

Further information:
  • jaw
  • Temporomandibular joint
  • Broken jaw
  • TMJ arthrosis
  • Temporomandibular joint cracking
  • Jaw misalignment
  • Jawbone
  • Jaw pain
  • Further general information from the field of dentistry

  • tooth
  • dental care
  • Toothache
  • Orthodontics
  • Craniomandibular system
  • Maxillary sinus infection
  • Inflammation of the jaw
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