The two joints that move the jaw are called temporomandibular joints (TMJ). Some 12 per cent of the population experience TMJ problems at one time or another, with women suffering three times as much as men.
TMJ dysfunction is often associated with trauma (such as occurs with dental extractions or motorcycle accidents), malocclusion (when the upper and lower teeth don't meet properly), emotional problems, grinding or clenching of teeth at night, muscular imbalance, mechanical insults such as gum-chewing or pipe-smoking, and even unequal leg length.
Most usually, though, the problem occurs when the articular disc - the fibrous tissue or cartilage pad that sits between the bones making up the TMJ - is perforated or displaced.
Pain in front of the ear, popping or clicking sounds in the TMJ, limited jaw movements, tinnitus (ringing in the ears), difficulty in swallowing, loss of balance, and fatigue or tightness when chewing are all symptoms associated with TMJ dysfunction.
One of the best means of diagnosing this problem is through osteopathic or chiropractic physical evaluation. During such an assessment, the osteopath will:
* check out any facial asymmetry or malocclusion of the teeth
* measure the amount of jaw opening (40 mm for the average adult)
* look for any midline deviation of the mandible (lower jaw)
* palpate the TMJ during jaw motion to detect any abnormality
* assess any spasms or jaw noises (such as a click on opening)
* palpate the area around the TMJ for abnormalities and tenderness.
An X-ray or tomograph can also assess symmetry, bone positioning and any degenerative changes. MRI (magnetic resonance imaging) is sometimes useful for uncovering any misalignment of bones as well as soft tissues in all planes.
If you are diagnosed with any of these problems, it's preferable to try out a number of conservative treatments before considering surgery. An osteopath or chiropractor with experience in treating TMJ problems will first eliminate any of the above causes, and then begin appropriate manipulative therapy, such as the 'counterstrain' and 'muscle energy' techniques, which help to reposition the misaligned joint and reduce pain. Sometimes even treating the sacrum may help, as may the passive stretching of any tight or stiff pterygoid muscles (the muscles that move the TMJ) inside the mouth.
It's also useful for the patient to carry out a suitable exercise regime regularly at home.
Occasionally, dentists or orthodontists who are aware of osteopathic concepts and techniques may apply interocclusal stabilisation devices (splints, in essence) to be worn for several months to reposition the malocclusion. These usually involve frequent readjustments as the alignment of the jaw shifts.
Another useful device can help to decrease jaw muscle spasms which, in turn, will reduce the associated muscle pain.
Yet another device - an antibruxism pad, doctorese for an antitoothgrinding pad - can be worn during sleep to reduce the effects of nighttime teethgrinding on both the teeth and the muscles of the TMJ.
Harald Gaier is a registered homoeopath, naturopath and osteopath.
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