The Temporomandibular joint (TMJ), is a joint which holds the lower jaw (the mandible) to a part of the skull (the Temporal bone). It consists of a left and a right hinge joint. They can work independently or work together. It is one of the most complex joint in the human body. The two basic movements of the TMJ are rotation and translation. If you place your fingers in front of your ears, you can feel that there is movement when you open your mouth. This movement is the translation of the joint. You may not be able to feel the rotation of the joint because it is a very small movement.
Anatomically, there is a disc located between the condyle and the temporal bone (1). Not only does the disk separate the condyle and the temporal bone, it also absorbs impact to the TMJ caused from chewing and other movements of the jaw. Furthermore, several major cranial nerves that exit the base of the skull pass through this area of the TMJ.
As with all joints in the human body, bone should never make direct contact with another bone. When this occurs, the condition is called arthritis. In cases of TMJ dysfunction, a series of symptoms arise.
Signs and Symptoms of TMJ Dysfunction
The following are some of the most common TMJ dysfunction symptoms:
- Headaches (often misdiagnosed as migraines)
- Earaches, ringing of ears, vertigo
- Pain behind the eyes.
- Clicking and popping of the TMJ when you open your mouth.
- Jaw gets locked open
- Bite is altered and teeth do not come together normally.
- Limited opening of the mouth.
- Mouth shifts to one side during opening.
- Neck and shoulder pain
- Myofascial pain
What causes TMJ Disorders?
If you read through most medical literature, you will usually find a common theme. They all state that for most jaw joint problems, scientists do not know the exact cause. In addition, they say there is no scientific proof that clicking and popping in the jaw joint can lead to serious problems. Unfortunately, those literatures can be misleading. A normal joint will not make popping, clicking, or grinding noises as they move.
Clicking and popping of the TMJ is one of the most misdiagnosed symptoms during a dental exam. Many dental healthcare providers will ask about their patient’s TMJ, but do not treat any TMJ dysfunction. Unfortunately, sometimes TMJ disorders are not even questioned during an exam. If the problem is not addressed, it can lead to worsening of the joint overtime.
How are TMJ Disorders treated?
When treating TMJ disorders, it is of utmost importance to treat the cause, not the symptoms. Continually taking pain medication to decrease TMJ pain is only treating the symptom and not the underlying cause. Therefore, it is important to treat the TMJ itself to have a better and stable outcome.
The following is a list of common treatment methods used by most health care providers. However, these are only treating the symptoms, not the cause.
- Eat soft foods.
- Apply heat packs.
- Avoid extreme jaw movement.
- Learn techniques for relaxing and reducing stress.
- Practice gentle jaw stretching exercises.
- Pain medication.
- Botox injection.
- Physical Therapy.
Again, all the above treatment modalities are treating the symptoms, not the cause.
Practicing gentle jaw stretching exercises can make the TMJ worse. If the disk is dislocated in front of the condyle, stretching exercises will further push the disc forward and cause even more damage. Botox injections must be delivered every 3-4 months. This means the patient will have to get these injections for years and years, possibly forever.
A normal TM joint does not make any noise. The disc follows the movement of the condyle as it translates forward. The disc always separates the condyle and the temporal bone as it moves forward. This movement is shown in Diagram 2.
Clicking and popping of the TMJ
The dental term of popping of the TMJ is called internal derangement. This is the main cause of the TMJ Disorder. What this means is that the normal anatomy of the condyle and the disc is in an abnormal position. The disc is being displaced in front of the condyle or to the side of the condyle. And as the condyle moves forward, the disc snaps back on top of the condyle. This is what causes the clicking or popping sound (3).
If the disk does not snap back on top of the condyle and remains in front of the condyle, it is called a closed lock. The patient is then unable to open his or her mouth wide (4).
After several years of this constant friction, the disk can be perforated causing arthritis in the joint (5).
At Legacy Dental Care, we treat TMJ patients by treating the cause of the problem. We simply rearrange the patient’s jaw using a mouth appliance and put the disc back to its normal anatomical position. In most cases, this does not require any surgery.
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