TMJ: Temporomandibular joint – This joint connects the lower jaw to the skull. It is actually made up of two joints on each side of the jaw that allow rotation and slide. In this site, we will use the phrase jaw joint to refer to the temporomandibular joint for ease of reading.
TMD: Temporomandibular disorder – an inflammation of the temporomandibular joint.
For simplicity we will refer to TMD as TMJ in this site as TMJ is the common term for a disorder of the temporomandibular joint. It is an acute or chronic inflammation of the joint connecting the lower jaw to the skull, or of the muscles surrounding it. It can cause pain or discomfort of the joint and surrounding area, including earaches, and can be a cause or a result of bruxism. According to one study, over 11% of teenagers experience TMJ pain.
Signs and Symptoms of TMD/TMJ
Below, we classify the different signs and symptoms of TMJ, while also briefly explaining each of them:
Popping or clicking sounds in the temporomandibular joint – Popping and clicking of the joint is quite normal and is a sign of wear on the bone and cartilage of the joint. It can be a symptom of mild TMJ, .
Abnormal movement of the jaw when opening – Two classic symptoms of TMJ are that the jaw ‘deviates’ (moves slightly sideways as the mouth opens) or ‘deflects’ (moves sideways then back to its normal centre position as the mouth opens) .
Difficulty in opening your jaw – A common sign of TMJ is when you are unable to open your jaw as wide as normal (for instance, to yawn or eat) .
Jaw muscle pain – TMJ sufferers are likely to experience pain or tenderness to the jaw joint or surrounding muscles if they are massaged, pressed, or palpitated. Pain in that area during eating, speaking, clenching, or in general, is also a common symptom.
Ear, neck, shoulder or facial pain – Earache from the inflammation of tissue around the joint is a sign of TMJ.
Stress, anxiety, depression, troubled sleep – It has been found in various studies that TMJ sufferers are more likely to experience stress, anxiety, depression, or disturbed sleep.
Malocclusion – TMJ may put the jaw slightly out of alignment (when it deviates or deflects, as mentioned above) which in turn means you have irregular contact between the teeth of the top and bottom jaws.
Wobbly teeth – Irregular contact (malocclusion, above) puts extra pressure on some teeth which will eventually cause them to become mobile – shifting, or loosening.
Tooth loss – Severe malocclusion on wobbly teeth can cause them to fall out completely.
Bruxism – According to one study, the more intense your bruxism, the more signs and symptoms of TMJ will appear. It is a known cause of TMJ, as you will see in the bruxism article.
Diagnosis and Confirmation
Of course, all of the above symptoms can be related to other factors. But if you suspect you have bruxism or TMJ, you should be certain before you start treating it. Only your dentist or doctor can confirm this for you. They may prescribe a bite strip. A bite strip is a small device worn on one cheek over the jaw joint and muscles, and it has a small electrode that senses and records instances and severity of jaw muscle tension. Your dentist or doctor will then analyse this data and diagnose you.
Some websites recommend a test called hair analysis. This is just a method of analysing the hair for mineral imbalances and nutritional deficiencies. As you will see in Your Diet, there is a relationship between magnesium deficiency and bruxism (along with a list of magnesium-rich food you can include in your diet). You can ask your doctor about hair analysis, but if you are asking a doctor to confirm your bruxism they may have other more reliable methods anyway. You can also think about what you eat – the foods mentioned in Your Diet have other nutritional properties and are usually recommended as part of a healthy diet.
Causes of TMJ
Bruxism – According to one study, the more intense your bruxism, the more signs and symptoms of TMJ will appear. One reason is because extended or severe bruxism can lead to damage and malocclusion of the teeth, which in turn hinders the jaw joint from operating properly. Another connection between bruxism and TMJ is that bruxism fatigues and strains the facial muscles (to be specific, the muscles used in mastication, around the jaw joint). As we saw in What is TMJ/TMD?, unnecessary contractions of the temporomandibular muscles cause them to become painful and inflamed, leading to jaw pain (TMJ). In general, excessive clenching for whatever reason contributes to TMJ pain.
Other unnecessary chewing, biting and gnawing – Chewing your fingernails, gnawing on your pen, and chewing gum over-exert your jaw muscles by requiring repeated contractions of the muscles and cramping or fatiguing them. Thus it makes sense that chewing tough food such as toffee and beef jerky will contribute.
Jaw strain – Have you been shouting a lot lately or did you have an exceptionally tall sandwich for lunch? Both these activities open your jaw to its extent and can strain your jaw joints. (Also, if you said yes to the first question, see the comments about stress in Treatments).
Injury – If you have suffered a blow to your jaw, say through sport or a fall, it might have knocked your lower jaw or some teeth out of alignment. A misaligned jaw is deviated (as in Signs and Symptoms of TMJ), and displaced (or missing) teeth affect your occlusion.
Bipolar disorder – One study shows a relationship between bipolar disorder and TMJ.
Risks and Complications of Non-Treatment of TMJ
Why you should not leave your TMJ untreated:
Jaw dysfunction – Limited ability to open your jaw is a natural reflex reaction of painful TMJ. This means not being able to chew your food properly, or talk properly.
Associated pain in the face, neck, ears and shoulders – Inflammation of the joints or soft tissue surrounding them causes pain which sometimes refers to nearby areas such as facial muscles, ears, neck and shoulder muscles.
Treatments for TMJ
- Biofeedback – Biofeedback methods (see bruxism treatments) have also been tested on TMJ sufferers by placing electrodes over the masseter (jaw) muscles and monitoring muscle tension. Subjects are not asleep as in the biofeedback method for bruxism. Instead, when the electrodes sense a certain high level of masseter muscle tension, a stimulus will make the subject aware of their muscle tension, and train them to relax their muscles. A paper detailing such tests concludes that this method of treatment, supported by cognitive behavioral therapy (training your mind to think and react in more favourable ways), is effective in treating TMJ. Learn More… | Visit Retailer’s Website
- Medication – Of course, you can always get over-the-counter painkillers such as analgesics and anti-inflammatory medications.
- Botox – But what is interesting is that Botox has been shown to be an effective treatment for hypertrophy of the masseter muscles. Of course, Botox is expensive, needs repetitions every couple of months, and the effect weakens each time.
- Occlusal splints – Repositioning occlusal guards or splints can treat TMD by guiding the alignment of the jaw and occlusion when wearers open and close their mouths.
- TMD. (n.d.) In Wikipedia. Retrieved September 12, 2008, from http://en.wikipedia.org/wiki/Temporomandibular_joint_disorder
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- Giannini, A. J., Slaby, A. E., Gianetti, J. P., et. al. (1991). Correlates on physical examination of bipolar disorder. Turkish Journal of Biological and Medical Research, 2(1), 23-30.