Your temporomandibular joint is a hinge that connects your jaw to the temporal bones of your skull, which are in front of each ear. It lets you move your jaw up and down and side to side, so you can talk, chew, and yawn.
Problems with your jaw and the muscles in your face that control it are known as temporomandibular disorders (TMD). But you may hear it wrongly called TMJ, after the joint.
What Causes TMD?
We don’t know what causes TMD. Dentists believe symptoms arise from problems with the muscles of your jaw or with the parts of the joint itself.
Injury to your jaw, the joint, or the muscles of your head and neck -- like from a heavy blow or whiplash -- can lead to TMD. Other causes include:
-- Grinding or clenching your teeth, which puts a lot of pressure on the joint
-- Movement of the soft cushion or disc between the ball and socket of the joint
-- Arthritis in the joint
-- Stress, which can cause you to tighten facial and jaw muscles or clench the teeth
What Are the Symptoms?
TMD often causes severe pain and discomfort. It can be temporary or last many years. It might affect one or both sides of your face. More women than men have it, and it’s most common among people between the ages of 20 and 40.
Common symptoms include:
-- Pain or tenderness in your face, jaw joint area, neck and shoulders, and in or around the ear when you chew, speak, or open your mouth wide
-- Problems when you try to open your mouth wide
Jaws that get "stuck" or "lock" in the open- or closed-mouth position
-- Clicking, popping, or grating sounds in the jaw joint when you open or close your mouth or chew. This may or may not be painful.
-- A tired feeling in your face
-- Trouble chewing or a sudden uncomfortable bite -- as if the upper and lower teeth are not fitting together properly
Swelling on the side of your face (www.webmd.com)