TemporoMandibular Joint (TMJ)
TMJ refers to the temporomandibular joint which is the joint which connects the temporal bone of the cranium and lower jaw together. Bruxism, which is teeth grinding and teeth clenching can wear down teeth, cause malocclusion, and increase the wear on the cartilage lining of the joint.
Emotional stress is often the underlying cause of a TMJ disorder, as it can contribute to people either consciously or unconsciously tightening facial and jaw muscles and grinding or clenching their teeth.
Habits like excessive gum chewing or fingernail biting also can cause jaw muscles to be overused.
A specially molded bite guard can be created to stop teeth grinding during the night and prevent TMJ deterioration.
Temporomandibular Disorders (TMD)
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 a toothache, sinus problems, arthritis, or gum disease – your dentist will conduct a careful patient history and physical examination to determine the cause of your symptoms.
Your dentist will examine your temporomandibular joints for pain or tenderness; listen for clicking, popping, or grating sounds during jaw movement; look for limited motion or locking of the jaw while opening or closing the mouth; and examine bite and facial muscle function. Sometimes panoramic X-rays will be taken. These full face X-rays allow your dentist to view the entire jaws, temporomandibular joint, and teeth to make sure other problems aren't causing the TMD symptoms. Sometimes, other imaging tests, such as magnetic resonance imaging (MRI) or a computer tomography (CT), are needed. The MRI views the soft tissue such as the TMJ disc to see if it is in the proper position as the jaw moves. A CT scan helps view the bony detail of the joint.
Your dentist may decide to send you to an oral surgeon (also called an oral and maxillofacial surgeon) for further care and treatment. This oral health care professional specializes in surgical procedures in and about the entire face, mouth, and jaw area.
What Treatments Are Available for TMD?
Treatments for TMD range from simple self-care practices and conservative treatments to injections and surgery. Most experts agree that treatment should begin with conservative, nonsurgical therapies first, with surgery left as the last resort. Many of the treatments listed below often work best when used in combination.
Basic Treatments for TMD
Some basic, conservative treatments for TMD include:
- Apply moist heat or cold packs. Apply an ice pack to the side of your face and temple area for about 10 minutes. Do a few simple stretching exercises for your jaw (as instructed by your dentist or physical therapist). After exercising, apply a warm towel or washcloth to the side of your face for about 5 minutes. Perform this routine a few times each day.
- Eat soft foods. Eat soft foods such as yogurt, mashed potatoes, cottage cheese, soup, scrambled eggs, fish, cooked fruits and vegetables, beans, and grains. In addition, cut foods into small pieces to decrease the amount of chewing required. Avoid hard and crunchy foods (like hard rolls, pretzels, raw carrots), chewy foods (like caramels and taffy) and thick and large foods that require your mouth to open wide to fit.
- Take medications. To relieve muscle pain and swelling, try nonsteroidal anti-inflammatory drugs (NSAIDs), such as naproxen or ibuprofen (Advil, Motrin, Aleve). Your dentist can prescribe higher doses of these or other drugs for pain relief. Muscle relaxants, especially for people who grind or clench their teeth, can help relax tight jaw muscles. Anti-anxiety medications can help relieve stress that is sometimes thought to aggravate TMD. Antidepressants, when used in low doses, can also help reduce or control pain. Muscle relaxants, anti-anxiety drugs, and antidepressants are available by prescription only.
- Low-level laser therapy. This is used to reduce the pain and inflammation, as well as increase range of motion to the neck and in opening the mouth.
- Wear a splint or night guard. Splints and night guards are plastic mouthpieces that fit over the upper and lower teeth. They prevent the upper and lower teeth from coming together, lessening the effects of clenching or grinding the teeth. They also correct the bite by positioning the teeth in their most correct and least traumatic position. The main difference between splints and night guards is that night guards are only worn at night and splints are worn all the time. Your dentist will discuss with you what type of mouth guard appliance you may need.
- Undergo corrective dental treatments. Corrective treatments including replacing missing teeth and using crowns, bridges, or braces to balance the biting surfaces of your teeth or to correct a bite problem.
- Avoid extreme jaw movements. Keep yawning and chewing (especially gum or ice) to a minimum and avoid extreme jaw movements such as yelling or singing.
- Don't rest your chin on your hand or hold the telephone between your shoulder and ear. Practice good posture to reduce neck and facial pain.
- Keep your teeth slightly apart as often as you can to relieve pressure on the jaw. To control clenching or grinding during the day, place your tongue between your teeth.
- Learning relaxation techniques to help control muscle tension in the jaw. Ask your dentist about the need for physical therapy or massage. Consider stress reduction therapy, including biofeedback.
More Controversial Treatments for TMD
When the basic treatments listed above prove unsuccessful, your dentist may suggest one or more of the following treatments for TMD:
- Transcutaneous electrical nerve stimulation (TENS). This therapy uses low-level electrical currents to provide pain relief by relaxing the jaw joint and facial muscles. This treatment can be done at the dentist's office or at home.
- Ultrasound. Ultrasound treatment is deep heat that is applied to the TMJ to relieve soreness or improve mobility.
- Trigger-point injections. Pain medication or anesthesia is injected into tender facial muscles called "trigger points" to relieve pain.
- Radio wave therapy. Radio waves create a low level electrical stimulation to the joint, which increases blood flow. The patient experiences relief of pain in the joint.
Surgery for TMD
Surgery for TMD should only be considered after all other treatment options have been unsuccessful. Because surgery is irreversible, it is wise to get a second or even third opinion from other dentists.
There are three types of surgery for TMD: arthrocentesis, arthroscopy, and open-joint surgery. The type of surgery needed depends on the TMD problem.
- Arthrocentesis. This is a minor procedure performed in the office under general anesthesia. It is performed for sudden-onset, closed lock cases (restricted jaw opening) in patients with no significant prior history of TMJ problems. The surgery involves inserting needles inside the affected joint and washing out the joint with sterile fluids. Occasionally, the procedure may involve inserting a blunt instrument inside of the joint. The instrument is used in a sweeping motion to remove tissue adhesion bands and to dislodge a disc that is stuck in front of the condyle (the part of your TMJ consisting of the "ball" portion of the "ball and socket")
- Arthroscopy. Patients undergoing arthroscopic surgery for TMD first are given general anesthesia. The surgeon then makes a small incision in front of the ear and inserts a small, thin instrument that contains a lens and light. This instrument is hooked up to a video screen, allowing the surgeon to examine the TMJ and surrounding area. Depending on the cause of the TMD, the surgeon may remove inflamed tissue or realign the disc or condyle.
Compared with open surgery, this surgery is less invasive, leaves less scarring, and is associated with minimal complications and a shorter recovery time. Depending on the cause of the TMD, arthroscopy may not be possible, and open-joint surgery may be necessary.
Open-joint surgery. Patients undergoing open-joint surgery also are first given general anesthesia. Unlike arthroscopy, the entire area around the TMJ is opened so that the surgeon can get a full view and better access. There are many types of open-joint surgeries. This treatment may be necessary if:
- The bony structures that comprise the jaw joint are deteriorating
- There are tumors in or around your TMJ
- There is severe scarring or chips of bone in the joint
- Compared with arthroscopy, open-joint surgery for TMD results in a longer healing time and there is a greater chance of scarring and nerve injury.