Bruxism is when a person grinds or clenches their teeth while not chewing. It typically occurs during sleep, and the person often does not know they are doing it. Causes include teeth growing, a misaligned bite, stress, and more.

Teeth grinding involves making a chewing motion in which the teeth rub against each other. Clenching is when a person holds their teeth together and clenches the muscles without moving the teeth back and forth.

People can grind or clench their teeth during the day or night. According to the United Kingdom’s Bruxism Association, 8–10% of the population experience it.

In this article, we look at the signs, diagnosis, and treatment of bruxism. We also explain the differences between bruxism during sleep and when awake.

A woman lying in bed wincing due to the pain of bruxism, or teeth grinding, during sleep.Share on Pinterest
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Sleep bruxism is a type of sleep disorder. The symptoms of sleep bruxism that people may notice when awake include:

  • facial pain
  • jaw pain and stiffness
  • clicking, popping, or grinding noises when moving the jaw
  • a dull headache
  • sensitive, loose, or broken teeth
  • worn teeth
  • broken or loose fillings

People can also experience ear pain because the temporomandibular joint (TMJ) — the joint that allows the jaw to open and shut — is very close to the ear. People may also have referred pain, which is when someone feels pain in a location other than its source.

Although people with bruxism during sleep often cannot feel that they are clenching or grinding the teeth, people who sleep near them may be able to hear the noise it causes.

Awake bruxism is different than sleep bruxism, as it is not a sleep disorder. Instead, it is an unconscious habit.

Often, awake bruxism does not cause teeth grinding. Instead, people are more likely to clench their teeth or tense the muscles around the jaw. Awake bruxism also causes aching around the jaw, dull headaches, and stiffness. However, in cases where there is no grinding, the condition may not wear the teeth in the same way.

As with sleep bruxism, awake bruxism happens involuntarily. People may notice that they are more prone to it when they are concentrating or feel stressed.

Bruxism does not always have a single or identifiable cause, but a number of factors are associated with it. These factors vary depending on the type of bruxism.

Primary bruxism

Primary bruxism occurs on its own and does not result from another condition. Some of the known factors that contribute to it include:

  • Growing teeth: Bruxism is common in young children, with up to 40% experiencing it, usually when their teeth are growing. However, because the teeth and jaw grow quickly during childhood, the bruxism usually resolves on its own without causing lasting damage.
  • Misaligned bite: In some people, bruxism may happen because either a person’s bite is not aligned or they have missing teeth. Irritation in the mouth may also contribute to grinding or clenching.
  • Stress: One of the main causes of bruxism in adults, whether it occurs during sleep or when awake, is stress. A 2020 systematic review found that there was a significant association between stress and bruxism, but more research is necessary to understand the relationship.
  • Smoking, alcohol, and caffeine: A 2016 review of previous research found that the use of these substances was also associated with bruxism. People who smoked or drank alcohol regularly were about two times more likely to have bruxism, while those who drank more than 8 cups of coffee per day were 1.5 times more likely.

Secondary bruxism

Secondary bruxism occurs as a result of another medical condition or circumstance, such as:

  • Mental health conditions: Anxiety and depression are associated with bruxism. This association may be due in part to stress, which can contribute to these conditions.
  • Neurological conditions: Conditions such as Huntington’s disease and Parkinson’s disease can cause movement during sleep, which may result in bruxism.
  • Medications: Bruxism can be a side effect of certain medications, including some antidepressants and antipsychotics. A 2018 study found a link between selective serotonin reuptake inhibitors (SSRIs) and bruxism. Fluoxetine (Prozac) and sertraline (Zoloft) were the most common culprits out of the studied drugs.
  • Sleep apnea: Sleep apnea is a condition that causes breathing to stop temporarily during sleep. It can reduce sleep quality and cause frequent arousals, which may be why it is a risk factor for bruxism. By disturbing sleep, sleep apnea may promote teeth grinding or clenching.

Long-term damage from bruxism may cause:

  • tooth sensitivity, due to enamel wearing away
  • gum inflammation or bleeding
  • loose teeth
  • damage to dental work, such as crowns and fillings
  • flattened or short teeth
  • tooth fractures
  • TMJ syndrome, which causes pain, tension, and difficulty chewing

A dentist can diagnose bruxism by performing a dental examination. They may notice:

  • worn tooth enamel
  • flattened, fractured, or chipped teeth
  • loose or damaged crowns and fillings
  • enlarged jaw muscles

Tooth wear can also result from overly vigorous brushing, abrasives in toothpaste, acidic soft drinks, and hard foods, but a trained professional can tell the difference between the characteristic wear patterns of each cause.

Various treatments and strategies may help with bruxism. These include:

Mouthguard or mouth splint

A dentist may recommend wearing a mouth splint or mouthguard during sleep to protect the teeth from damage. These devices can help by evening out the pressure across the jaw, providing a physical barrier between the teeth, and reducing the noise of teeth grinding.

Mouthguards for bruxism usually consist of flexible rubber or plastic. A dentist can create one that is tailored to an individual’s teeth, or a person can buy an over-the-counter (OTC) version. OTC versions may be less comfortable.

Mouth splints are typically made of harder plastic and fit directly onto the teeth. Some splints fit over the top teeth, while others fit on the bottom teeth. Depending on the design, a splint will keep the jaw in a more relaxed position or provide a barrier so that the splints, rather than the teeth, sustain any damage.

It is not advisable to use generic mouthguards for sports, as they can be bulky and cause significant discomfort.

Medication

Taking a nonsteroidal anti-inflammatory drug (NSAID), such as ibuprofen, may help relieve any pain and swelling associated with bruxism.

In some cases, a doctor may also recommend the short-term use of a medication to relax the muscles and stop the cycle of teeth grinding. This approach gives the jaw muscles a chance to rest, which may reduce symptoms.

If a medication could be causing bruxism as a side effect, a person may wish to speak with a doctor about changing to an alternative. A person should never stop a medication or change the dosage without consulting a doctor first.

Biofeedback

Biofeedback is a type of therapy that helps someone become aware of involuntary bodily functions, such as breathing or heart rate, and teaches them to control them.

There is not a lot of research on the effectiveness of biofeedback for treating bruxism, but a 2018 review did find some evidence that a specific biofeedback tool known as contingent electrical stimulation improved symptoms after several nights of use.

Botox

In severe cases of bruxism, injections of botulinum toxin, or Botox, can paralyze the muscles responsible for sleep bruxism to stop teeth grinding. However, Botox can be expensive, and regular injections are necessary to maintain the effects.

Treatment for underlying conditions

If a person with bruxism also experiences stress, anxiety, or depression, seeking help for these conditions may help with their teeth grinding.

Usually, treatment for these mental health conditions involves a combination of talk therapy and medication to reduce the symptoms, but as some SSRIs can cause bruxism as a side effect, a person may wish to start with therapy first.

Alternatively, if an individual has a condition such as sleep apnea, speaking with a doctor about this may allow them to get a diagnosis and treatment. For example, some people with sleep apnea benefit from using a continuous positive airway pressure machine to prevent sleep disruptions.

People with primary bruxism may be able to reduce or prevent the symptoms by practicing self-care. For example, they can try:

  • avoiding alcohol, tobacco, and caffeine
  • refraining from chewing gum, as this may increase wear and tear or encourage more grinding
  • applying gentle heat to the jaw to relieve pain and tension
  • reducing avoidable stress and taking steps to manage unavoidable stress

External events and circumstances can cause stress, but it can also come from how people perceive those events. In either case, there are ways to manage it.

Seeking support, making time for relaxation, and practicing mindfulness can help. People may also wish to try breathing exercises, meditation, yoga, or other relaxation techniques.

Here are some answers to questions that people often have about bruxism.

Can bruxism cause tinnitus?

It is possible that bruxism and tinnitus might be linked. According to the American Tinnitus Association, tinnitus can occur if the TMJ becomes damaged. As bruxism directly affects this joint, it may lead to tinnitus.

Is bruxism hereditary?

An older review of previous research concluded that there is some evidence that bruxism may run in families. However, no study has identified specific genes that are related to it, and genetics is likely only one of many contributing factors.

Bruxism is when a person grinds or clenches their teeth involuntarily. It can occur when someone is awake or asleep, causing facial pain, jaw stiffness, and headaches. In the long term, teeth grinding can damage the teeth, gums, or jaw joint.

A dentist can diagnose bruxism during a dental exam. Treatment focuses on reducing damage to the teeth via a mouthguard or mouth splint and addressing factors that might be contributing to the bruxism. This may involve reducing stress, changing medications, or treating associated conditions, such as sleep apnea.