Bruxism: What’s behind the jaw clenching and teeth grinding?

Most people grind their teeth or clench their jaw at some point during their life. Under times of stress, while experiencing pain in the body, or perhaps as the result of having dental or orthodontic work. However, persistent teeth grinding and/or jaw clenching is known as bruxism, and is often a thing that would cause your dentist concern.

So, what exactly is bruxism?

In the simplest of terms, bruxism is habitual teeth grinding and/or jaw clenching. There are two forms of bruxism, awake bruxism and sleep bruxism. It’s estimated that 20% of the population suffers from awake bruxism, which generally involves clenching of the teeth and jaw. This behavior is most commonly in response to certain stimuli, such as when under stress or it may even be related to – or a side effect of – medication.

Sleep bruxism, which affects roughly 8% of the population, is characterized by involuntary teeth grinding with rhythmic and sustained jaw muscle contractions. Teeth grinding and jaw clenching at night is commonly linked to sleep disorders and disturbances, such as sleep apnea. During nighttime bruxism, the jaw can produce up to 800N/cm3 of force, which can last up to 20 minutes per interval. If you are wondering how much 800N of force is, a wolf’s jaw is only capable of 590N/cm3, and it takes roughly 600N to crack a walnut.

So, even though mental stress and tension may be abreacted, this reoccurring wear and tear causes damage and pain to the jaw and teeth.

Causes

It’s not completely clear why bruxism occurs. Researchers have attributed it to malocclusion, or a bad bite, as well as sleep disorders. In some cases, dental issues are also too blame. Crowns that are too high, improper fillings or bridges, missing teeth (gaps), poorly fitting prostheses, defective dental implants or orthodontic maladjustments may cause clenching and/or grinding.

Most illuminating though, is what recent research has discovered: that lifestyle and behavior (i.e. how we cope with stress) may be the primary cause

Consequences

People affected by sleep-bruxism often complain of sleep disturbances and painful teeth and temporomandibular joints (TMJ). They may also experience neck strain, facial muscle ache, headaches or migraines and tinnitus – or ringing in the ears.

Over the years, the accumulated toll of bruxing can be seen in following ways:

  • The teeth, especially the front teeth, are much shorter and the canines have no more tips.
  • Tooth enamel often shows cracks and advanced wearing.
  • Gum recession, due to pressure on the gum line.
  • Loose or broken teeth.
  • Headache and aching jaws due to overuse of muscles.

When being examined by the dentist, some patients who suffer from bruxism

experience an increase in pressure and sensitivity of the facial muscles and the TMJ, as well as clicking joints while opening the mouth.

Treatment

In many cases, treatment is not necessary. Children exhibiting signs of bruxism will often outgrow it. However, if the problem is severe, the condition can be managed through treatment. It is advised that you first consult your dentist and undergo an evaluation. Your dentist will be able to evaluate the extent of wear and tear on your teeth, gums and jaw and can best offer suggestions on how to offset further damage.

The following methods may not stop bruxism, but may help alleviate the wear and tear to the teeth and jaw:

Custom-fitting mouth guard: generally made from hard acrylic, this bite plate will absorb the clenching and grinding, preventing further damage to the teeth.
Dental corrections: if misaligned teeth or improper bit are part of the problem.
Stress/anxiety management: learning relaxation techniques, such as yoga, meditation and breathing exercises, or speaking to a counsellor or therapist may help.
Medications: in severe cases medications may be prescribed. Or in some cases where bruxism is a side effect of a drug, your doctor may change the dosage or prescribe a different drug.
Sleep disorders: in the event the bruxism is related to a sleep disorder, addressing the sleep disorder may help to alleviate the bruxism.