Temporomandibular Disorder (TMD)
What are the temporomandibular joints (TMJ)?
Simply stated, the temporomandibular joints (TMJ) are the two joints that connect your jaw to your skull. More specifically, they are the joints that slide and rotate in front of each ear, and consist of the mandible (the lower jaw) and the temporal bone (the side and base of the skull). According to the American Dental Association, the TMJs are among the most complex joints in the body. These joints, along with several muscles, allow the mandible to move up and down, side to side, and forward and back. When the mandible and the joints are properly aligned, smooth muscle actions, such as chewing, talking, yawning, and swallowing, can take place. When these structures (muscles, ligaments, jaw bone, mandible, TMJ) are not aligned, nor synchronized in movement, several problems may occur.
What is temporomandibular disorder (TMD)?
Temporomandibular disorders (TMD) are disorders of the jaw muscles, temporomandibular joints, and/or the nerves associated with chronic facial pain. Any problem that prevents the complex system of muscles, bones, and joints from working together in harmony may result in temporomandibular disorder.
The National Institute of Dental and Craniofacial Research, part of the National Institutes of Health, classifies the categories of TMD by the following criteria:
Myofascial pain. This is the most common form of TMD, which is discomfort or pain in the muscles that control jaw function and the neck and shoulder muscles.
Internal derangement of the joint. This means a dislocated jaw or displaced disk, or injury to the condyle (the rounded edges of the jaw).
Degenerative joint disease, such as osteoporosis or rheumatoid arthritis in the jaw joint.
A person can have one or more of these conditions at the same time.
What causes TMD?
In many cases, the actual cause of this disorder may not be clear. Sometimes the primary cause is excessive strain on the jaw joints and muscle group that controls chewing, swallowing, and speech. This strain may be a result of bruxism – the habitual, involuntary clenching or grinding of the teeth. But trauma to the jaw, the head, or the neck may cause TMD. Arthritis and displacement of the jaw joint disks can also cause TMD pain. In other cases, another painful medical condition such as fibromyalgia or irritable bowel syndrome may overlap with or amplify the pain of TMD. A recent study by the National Institute of Dental and Craniofacial Research identified clinical, psychological, sensory, genetic, and nervous system factors that may put a person at higher risk of developing chronic TMD.
What are the signs and symptoms of TMD?
The following are the most common signs and symptoms of TMD. However, each individual may experience symptoms differently. Signs and symptoms may include:
Jaw discomfort or soreness (often most prevalent in the morning or late afternoon)
Pain radiating behind the eyes, in the face, shoulder, neck, and/or back
Earaches or ringing in the ears (not caused by an infection of the inner ear canal)
Clicking or popping of the jaw
Locking of the jaw
Mouth motions are limited
Clenching or grinding of the teeth
Sensitivity of the teeth without the presence of an oral health disease
Numbness or tingling sensation in the fingers
A change in the way the upper and lower teeth fit together
The symptoms of TMD may resemble other conditions or medical problems. Consult a dentist or your doctor for a diagnosis.
What are the treatments for TMD?
Specific treatment for TMD will be determined by your physician or dentist based on:
Your age, overall health, and medical history
Extent of the disease
Your tolerance for specific medications, procedures, or therapies
Expectations for the course of the disease
Your opinion or preference
Treatment may include:
Resting the temporomandibular joint (TMJ)
Medication and/or pain relievers
Relaxation techniques and stress management
Behavior modification (to reduce or eliminate the clenching of the teeth)
An orthopedic appliance or mouthguard worn in the mouth (to reduce bruxism)
Diet modification (to rest the jaw muscles)
Ice and hot packs