Temporomandibular disorders (TMD) occur as a result of problems with the jaw, jaw joint and surrounding facial muscles that control chewing and moving the jaw. These disorders are often incorrectly called TMJ, which stands for temporomandibular joint.
What Is the Temporomandibular Joint (TMJ)?
The temporomandibular joint (TMJ) is the hinge joint that connects the lower jaw (mandible) to the temporal bone of the skull, which is immediately in front of the ear on each side of your head. The joints are flexible, allowing the jaw to move smoothly up and down and side to side and enabling you to talk, chew, and yawn. Muscles attached to and surrounding the jaw joint control the position and movement of the jaw.
What Causes TMD?
- The cause of TMD is not clear, but dentists believe that symptoms arise from problems with the muscles of the jaw or with the parts of the joint itself.
- Injury to the jaw, temporomandibular joint, or muscles of the head and neck – such as from a heavy blow or whiplash – can cause TMD. Other possible causes include:
- Grinding or clenching the teeth, which puts a lot of pressure on the TMJ
- Dislocation of the soft cushion or disc between the ball and socket
- Presence of osteoarthritis or rheumatoid arthritis in the TMJ
- Stress, which can cause a person to tighten facial and jaw muscles or clench the teeth
What Are the Symptoms of TMD?
People with TMD can experience severe pain and discomfort that can be temporary or last for many years. More women than men experience TMD, and TMD is seen most commonly in people between the ages of 20 and 40.
Common symptoms of TMD include :
- Pain or tenderness in the face, jaw joint area, neck and shoulders, and in or around the ear when you chew, speak, or open your mouth wide
- Limited ability to open the mouth very wide
- Jaws that get "stuck" or "lock" in the open- or closed-mouth position
- Clicking, popping, or grating sounds in the jaw joint when opening or closing the mouth (which may or may not be accompanied by pain) or chewing
- A tired feeling in the face
- Difficulty chewing or a sudden uncomfortable bite – as if the upper and lower teeth are not fitting together properly
- Swelling on the side of the face
- May occur on one or both sides of the face
- Other common symptoms of TMD include toothaches, headaches, neck aches, dizziness, earaches, hearing problems, upper shoulder pain, and ringing in the ears (tinnitis).
How Is TMD Diagnosed?
Because many other conditions can cause similar symptoms to TMD – including atoothache, sinus problems, arthritis, or gum disease – your dentist will conduct a careful patient history and physical examination to determine the cause of your symptoms.