What is the TMJ?
TMJ stands for the Temporo-Mandibular Joint, more commonly referred to as the Jaw Joint, which is just in front of your ear. The mandible (lower jaw) has two temporo-mandibular joints, one on each side, that work together to move the jaw. Muscles and ligaments work together to make the jaw move, and a disc and joint capsule cushion the movements of the jaw against the bones of the skull. The positions of the teeth,and of both the upper and lower jaw can have a major influence on, or be influenced by, the jaw joints. The spine, hips and feet can also play an important role in TMJ dysfunction.
What Can Go Wrong With The TMJ?
The TMJs and their muscles and their ligaments are subject to the same types of injury and pathology as any other joint in the body. The joints can be injured by trauma or overuse, become inflamed or degenerate, and be affected by systemic disease such as arthritis or osteporosis. If the joints are functioning incorrectly it is called a 'dysfunction' - so TMJ Dysfunction is often referred to as 'TMD'.TMD is more common in females. Teenage hormones seems to play a part and a fairly common genetic defect in the lumbar spine also has an effect. A lateral strain pattern in the skull is evident in many TMD cases.
A type of overuse injury that can occur in the TMJ is due to clenching and grinding of the teeth - a condition known as bruxism. This often occurs at night during sleep. A person with bruxism may experience pain (particularly in the joint or the muscles of the temples and face), unusual movements of the jaw (including cracking or creaking sounds), or may even be causing damage to their teeth. Teeth, fillings, crowns and veneers can be worn down, chipped or fractured as a result of bruxism.
If you are experiencing symptoms of TMJ dysfunction, or your teeth are showing signs of wear and tear, wearing a custom-designed splint called an Occlusal Splint may be recommended. The splint is designed to protect teeth, crowns and fillings from the damaging effects of bruxism, and may also reduce or remove the pain in the TMJs.
We often use an "NTI" mini splint which we have found personally to be very effective in reducing the symptoms if not correcting the problem.
The bite may need to be re-built with orthodontic or prosthodontic (crowns and build-up restorations) treatment to provide a stable result.
Other treatments include chiropractic care, physiotherapy and acupuncture. Surgery is an occasional option - e.g. with bad arthritis.
TMJ Analysis and Diagnosis
When it’s not functioning properly several symptoms present such as:
Clicking or locking jaws
- Pain in the joint, muscles and ligaments
Grinding and clenching the teeth
Headaches – including Migraines
Limited jaw opening
Tinnitus (ringing in the ear)
Eye pain and light sensitivity
Pain around the head and face
Neck and shoulder problems, and many more obsure problems
Only the lower jaw (Mandible) is able to move. The upper jaw (Maxilla) is part of the skull. If the maxilla or mandible are not correctly aligned on closure to each other, and to the other bones of the skull TMD is inevitable.
The teeth close only where they fit together the best. This may not be where the muscles and ligaments suspending and moving the jaw actually want to be. This in turn can lead to muscle spasm and cramping.
There is a disc which sits on the top of the lower jaw which acts as a shock absorber and allows the jaw to slide freely. It can become dislocated. If it 'pops'back into place you may hear a click, if it stays displaced opening is usually restricted and may be painful.
Sometimes like a 'dicky knee' the TM joint will never be perfect, and it needs to be nursed along by avoiding hard foods and wide opening.
A Normal T.M.J.