The Same Old Grind

Do you notice clicking or popping sounds when you open your mouth? Is it difficult or painful to yawn or open your mouth wide? Does your jaw intermittently lock?

If so, you should see your dentist for an examination and evaluation. You may have a temporomandibular disorder (TMD) – one of several problems involving the chewing muscles, the jaw joint (called the temporomandibular joint or TMJ) or both.

Here are some key symptoms linked to TMD.

Unusual sounds - Clicking, grinding or popping sounds when you open your mouth are common in people with TMD. The sounds may or may not be accompanied by increased pain. Researchers believe that most people with popping or clicking in the jaw joint likely have a displaced disc. However, as long as the displaced disc causes no pain or problems with jaw movement, no treatment is needed.

Locking or limited movement - The jaw joint, which is a ball-and-socket joint, may intermittently lock in an open position. You also may have difficulty opening your mouth because it feels locked or is painful. Ear pain - You may initially think you have an ear infection, but it may be TMD. Pain from TMD is usually felt in front of or below the ear. Headaches - One study showed that up to 80 percent of patients with TMD report having headaches.

Morning stiffness or soreness - If your jaw muscles are stiff and sore when you wake up, it may by a sign that you are clenching or grinding your teeth in your sleep, which can tire the jaw muscles and lead to pain.

Difficulty chewing - You may experience difficulty chewing as a result of a change in your bite - the way your upper and lower teeth fit together. This shift in your bite may be an indication of TMD.

Previous injuries and related conditions - A recent injury to the jaw joint or one from many years past can cause TMD. Arthritis in the joint may also arise from injury, or if you already have arthritis in other joints, it may move to the TMJ, causing TMD.

In evaluating and diagnosing your condition, your dentist will test the jaw's range of motion, measuring how far you can open your mouth and move the jaw from side to side. Your dentist also will feel the jaw joint and muscles for pain and tenderness and listen to the jaw joint, using a stethoscope placed in front of the ear to evaluate any clicking, popping or grinding sounds during movement.

X-rays are often taken to look at the TMJ and in some cases a computer tomography (CT) scan may be needed to further examine the bony detail of the joint. In addition, magnetic resonance imaging (MRI) is sometimes recommended to analyze the soft tissues.

While it is advisable to discuss any TMD symptoms you may notice with your dentist, occasional discomfort in the jaw joint and chewing muscles is quite common and generally not a cause for concern. However, should you be diagnosed with TMD, the good news is that simple self-care practices are highly effective in relieving the discomfort.

These include eating soft foods, applying heat or ice packs and avoiding extreme jaw movements. Conservative treatments, including physical therapy and mouth guards, also are effective.

Source: Lawrence M. Levin, D.M.D., M.D., chief of the division of oral and maxillofacial surgery at the University of Pennsylvania Medical Center and an assistant professor at the university's School of Dental Medicine.