The temporomandibular joint (TMJ) connects the lower jaw or mandible to the temporal bone of the skull. These bony structures are supported by muscles and ligaments to function harmoniously.
The head of the lower jaw, also called the condyle, fits into a depression of the temporal bone. A cartilage or articular disc cushions the joint and acts as a shock absorber between the two bones.
A normal, healthy temporomandibular joint allows one to open his mouth wide enough to fit three fingers between the upper and lower teeth. During mouth opening the articular disc stays between the condyle and the depression without being dislocated and without causing pain or discomfort.
What is TMD?
A temporomandibular disorder (TMD) is a condition where the TMJ is not functioning normally. This occurs when the articular disc is displaced or is not in its proper position. This may be brought about by misalignment of the teeth or when one’s bite is not normal, such as a deep overbite or when the lower jaw lies too far back. The jaw may also be dislocated when one has a narrow upper jaw or when the upper front teeth are crooked and positioned backwards. These abnormalities can cause the lower jaw to be pulled far backwards leading to compression of nerves and blood vessels. These lead to pain and other symptoms typical of TMDs.
When the protective cartilage disc is displaced forward it no longer acts as a cushion between the condyle of the lower jaw and the socket in the skull. Eventually this can cause the condyle to constantly rub against the socket. This can cause degenerative changes called osteoarthritis.
These mild displacements may be felt with a clicking or a popping sound in the joint of the jaw during opening and closing of the mouth.
With severe jaw displacement one can feel more intense pain and permanent damage to the joint may occur. These can lead to other symptoms which include:
- Severe headaches
- Neck pains
- Tinnitus or ringing in the ear
- Stuffiness of the ears
- Pain felt behind the eyes
- Shoulder pains
- Lower back pains
- Dizziness, sometimes fainting
- Difficulty in swallowing
- Tingling sensation in the fingers and hands
Types of TMJ Dysfunction
There are different types of TMDs according to cause of dysfunction.
- Muscle Disorders – These are conditions which primarily affect the muscles of chewing or mastication, including diseases of the muscles such as dermatomyositis, polymyositis, hereditary myopathy, and changes in the muscles due to functional disturbances (eg: bruxism – teeth grinding related to stress, anxiety, etc).
- Joint Disorders – These include derangements of the TMJ such as a displaced disc, a dislocated jaw or a bone injury.
- Degenerative Joint Disease – Usually caused by osteoarthritis of the jaw
A TMD may also be caused by one or more factors.
Management of Temporomandibular Disorders
Symptoms of temporomandibular disorder may be mild and self-limiting, and only a few people may seek consultation. However, if left untreated TMDs may persist and symptoms may recur or worsen.
Upon seeking medical consultation, a patient’s complete medical history is taken. A physical, as well as a dental examination is done to evaluate the patient’s orofacial structures and neurological function. This includes assessment of one’s audiological function, speech, functional range of jaw motion, swallowing problems, dental status and evidences of teeth grinding and clenching. Psycho social function is also evaluated since stress and anxiety can contribute to the patient’s symptoms and functional status.
Laboratory workup may be done to confirm structural changes using radiological examinations, CT scan or MRI. Other tests may be done to rule out other possible conditions.
Many cases of TMJ disorders are self-limiting and may be managed with patient education and self-management. Teeth clenching and grinding (bruxism), for example, may be treated with rest, relaxation, behavioral modification and stress management.
Some patients may need pharmacological treatment with nonsteroidal anti-inflammatory drugs (NSAIDs) and opiates to control pain, muscle relaxants to reduce muscle spasms and antidepressants to reduce stress and anxiety.
Physical therapy may also help in patients with musculoskeletal and neurological disorders. Intraoral splints to stabilize the jaw are sometimes used in patients with dental problems.
A few patients may need more aggressive treatment for their symptoms such as occlusal therapy or surgery.
Botox Injections: An Alternative Therapy for TMD in London
Injecting small amounts of Botulinum toxin A, also called Botox, into the masseter muscle (the principal jaw muscle) is an effective way to treat many temporomandibular joint disorders. This substance reduces muscle spasm and relaxes the masseter, resulting in relief of pain and other symptoms associated with TMD including bruxism (clenching & grinding of teeth). With time, destruction of teeth and gums are avoided and degenerative changes in the joint are reduced.
Studies show that Botox injection is an effective and safe way to treat many disorders associated with muscle spasm such as blepharospasm (in the eyelids) and strabismus (eye muscle spasm), excessive sweating (hyperhidrosis), and migraine headaches.
Botox treatment provides a safe and easy way to treat various temporomandibular joint disorders, including bruxism. These injections may be administered within a few minutes in a doctor’s office or an outpatient setting. There is no need for hospitalization and no down time for the patient. Positive results are immediate, and relaxation of the jaw muscles may be experienced within a few days. Results may last for 4-6 months and the patient has the option to receive additional treatments if needed.
When to Consult a Doctor
If you have these symptoms, you may need treatment for TMD:
- Jaw muscles ache especially in the morning
- Difficulty in chewing
- Frequent headache/Migranes
- Premature wearing of teeth
- Neck and shoulder pain
- Vertigo (dizziness)
- Someone notices you make grinding noises while you asleep
- Presence of high risk factors such as sleep disorders, stressful lifestyle, high alcohol and caffeine intake, smoking, use of antidepressants or sleep pills
TMJ Disorders. NIDCR. http://www.nidcr.nih.gov/OralHealth/Topics/TMJ/TMJDisorders.htm
The Temporomandibular Joint, Closed. NIDCR. http://www.nidcr.nih.gov/imagegallery/oralhealth/TMJDisordersClose.htm