Bruxism: Why You Clench or Grind Your Teeth and What You Can Do

Bruxism is repetitive jaw-muscle activity that makes you clench or grind your teeth, or hold your jaw tense or pushed forward. It can happen during sleep or while awake, and many people don’t know they have it. It does not always cause problems, but when it is intense it can wear down teeth, fracture restorations or cause jaw discomfort.

Picture this hypothetical scene: Andrea is 34 and for months has been waking up with a tired jaw and a dull ache in her temples. Her partner tells her that on some nights he hears a sound like stones rubbing together. During the day at the office, Andrea notices her teeth are clenched while she answers emails. She never gave it much thought until the edge of a front tooth chipped.

What exactly is bruxism?

In 2013 an international group of experts proposed a consensus definition: bruxism is a repetitive jaw-muscle activity characterized by clenching or grinding of the teeth and by bracing or thrusting of the jaw. They distinguished two forms depending on the time of day: sleep bruxism and awake bruxism (Lobbezoo et al., 2013). In a later update, the same group proposed separate definitions for each form and put forward an important idea: in otherwise healthy people, bruxism should not be considered a disorder in itself, but a behavior that can become a risk factor for some problems (Lobbezoo et al., 2018).

How common is it?

It is quite common. A systematic review of studies in adults found that awake bruxism is reported more often than sleep bruxism, and that the latter tends to decrease with age (Manfredini et al., 2013). A population study in the Netherlands confirmed that both forms are common in the general adult population and that many people have both (Wetselaar et al., 2019). Because much of this data relies on what people report, many cases probably go unnoticed.

Why does it happen?

For years bruxism was thought to be caused by a “misaligned” bite. Today the evidence points elsewhere. In sleep bruxism, episodes are usually associated with micro-arousals, brief activations of the brain and nervous system during sleep, which indicates that its origin is mainly central rather than related to how the teeth fit together (Lavigne et al., 2008).

Many related factors have been studied: stress and anxiety, tobacco, alcohol and caffeine use, some medications, sleep disorders such as apnea and certain personality traits. A review pooling multiple systematic reviews found associations with several of these factors, though it noted that the quality of the evidence is still limited (Melo et al., 2019). In awake bruxism, emotional tension and intense concentration, such as working at a screen, often play a prominent role.

Signs that may give it away

• Waking up with a tired, stiff or sore jaw.
• Headache on waking, especially in the temples.
• Grinding noises at night, noticed by someone else.
• Flat or shiny wear on the edges of the teeth.
• Repeated fractures of teeth or restorations.
• Tooth marks along the edges of the tongue or inside the cheeks.
• Noticing during the day that you keep your teeth together or your jaw tense.

The international consensus proposes grading the diagnosis: “possible” when it is based only on what the person reports, “probable” when there are also examination findings and “definite” when confirmed with instrumental recordings, such as a sleep study (Lobbezoo et al., 2013).

Is it related to jaw pain?

Bruxism is often linked with temporomandibular disorders, which include pain in the chewing muscles or the jaw joint. A systematic review found an association between the two, especially in studies based on self-report, but concluded that bruxism has not been shown to be the direct cause of these disorders (Manfredini & Lobbezoo, 2010). In other words, they can appear together, but the relationship is more complex than once thought.

What can be done?

There is no definitive “cure,” but there are ways to reduce its effects. Specialists propose a management approach that combines several strategies depending on each case (Manfredini et al., 2017).

Awareness and habits

For awake bruxism, learning to notice when you clench is the first step. The ideal resting position is lips together, teeth slightly apart and tongue relaxed. Some people use phone reminders or notes on their screen to check their jaw throughout the day. Cutting back on caffeine, alcohol and tobacco, and improving sleep habits, can also help.

Splints or night guards

An occlusal splint is a rigid device worn at night. Its main benefit is protecting the teeth from wear and fractures. However, a Cochrane review concluded that there is not enough evidence to state that it reduces sleep bruxism itself (Macedo et al., 2007). A more recent review of oral appliances found variable results and noted that better-quality studies are needed to know which device works best and for whom (Jokubauskas et al., 2018). Over-the-counter soft guards are not always advisable, because some people tend to chew on them more.

Other options

Botulinum toxin has been studied to reduce chewing-muscle activity. A systematic review found that it might decrease episodes and pain in some cases, but warned that the evidence is limited and more studies are needed before recommending it routinely (De la Torre Canales et al., 2017). If a sleep disorder such as apnea is suspected, a medical evaluation is worthwhile, because treating it may influence bruxism.

Frequently asked questions

Is bruxism always bad? Not necessarily. Many people have mild episodes without consequences. It becomes a problem when it causes wear, fractures, pain or disrupts sleep.

Does adjusting the bite stop bruxism? Current evidence does not support grinding down or modifying the teeth as a treatment for bruxism, because its origin is mainly central.

Do children grind too? Yes, it is common in childhood and often decreases with growth. If it comes with snoring or pauses in breathing, it is worth mentioning to the pediatrician.

The end of the story

In our hypothetical case, Andrea sought an assessment. She was told she probably had both sleep and awake bruxism, and was advised to use a rigid splint to protect her teeth at night. She also started using reminders to relax her jaw at work and cut back on afternoon coffee. Months later she still ground her teeth on some nights, but the morning pain had almost disappeared and her teeth were protected. Her story illustrates the central idea: bruxism cannot always be eliminated, but it can be managed.

If you want a professional to take a look

See the treatments at The Special Teeth. If you are coming from the United States, our guide to planning your visit to Tijuana helps with the border crossing and transfers. Whenever you are ready, you can request an evaluation.

References

De la Torre Canales, G., Câmara-Souza, M. B., do Amaral, C. F., Garcia, R. C. M. R., & Manfredini, D. (2017). Is there enough evidence to use botulinum toxin injections for bruxism management? A systematic literature review. Clinical Oral Investigations, 21(3), 727–734. https://doi.org/10.1007/s00784-017-2092-4

Jokubauskas, L., Baltrušaitytė, A., & Pileičikienė, G. (2018). Oral appliances for managing sleep bruxism in adults: A systematic review from 2007 to 2017. Journal of Oral Rehabilitation, 45(1), 81–95. https://doi.org/10.1111/joor.12558

Lavigne, G. J., Khoury, S., Abe, S., Yamaguchi, T., & Raphael, K. (2008). Bruxism physiology and pathology: An overview for clinicians. Journal of Oral Rehabilitation, 35(7), 476–494. https://doi.org/10.1111/j.1365-2842.2008.01881.x

Lobbezoo, F., Ahlberg, J., Glaros, A. G., Kato, T., Koyano, K., Lavigne, G. J., de Leeuw, R., Manfredini, D., Svensson, P., & Winocur, E. (2013). Bruxism defined and graded: An international consensus. Journal of Oral Rehabilitation, 40(1), 2–4. https://doi.org/10.1111/joor.12011

Lobbezoo, F., Ahlberg, J., Raphael, K. G., Wetselaar, P., Glaros, A. G., Kato, T., Santiago, V., Winocur, E., De Laat, A., De Leeuw, R., Koyano, K., Lavigne, G. J., Svensson, P., & Manfredini, D. (2018). International consensus on the assessment of bruxism: Report of a work in progress. Journal of Oral Rehabilitation, 45(11), 837–844. https://doi.org/10.1111/joor.12663

Macedo, C. R., Silva, A. B., Machado, M. A. C., Saconato, H., & Prado, G. F. (2007). Occlusal splints for treating sleep bruxism (tooth grinding). Cochrane Database of Systematic Reviews, 2007(4), Article CD005514. https://doi.org/10.1002/14651858.cd005514.pub2

Manfredini, D., & Lobbezoo, F. (2010). Relationship between bruxism and temporomandibular disorders: A systematic review of literature from 1998 to 2008. Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology, and Endodontology, 109(6), e26–e50. https://doi.org/10.1016/j.tripleo.2010.02.013

Manfredini, D., Serra-Negra, J., Carboncini, F., & Lobbezoo, F. (2017). Current concepts of bruxism. The International Journal of Prosthodontics, 30(5), 437–438. https://doi.org/10.11607/ijp.5210

Manfredini, D., Winocur, E., Guarda-Nardini, L., Paesani, D., & Lobbezoo, F. (2013). Epidemiology of bruxism in adults: A systematic review of the literature. Journal of Orofacial Pain, 27(2), 99–110. https://doi.org/10.11607/jop.921

Melo, G., Duarte, J., Pauletto, P., Porporatti, A. L., Stuginski-Barbosa, J., Winocur, E., Flores-Mir, C., & De Luca Canto, G. (2019). Bruxism: An umbrella review of systematic reviews. Journal of Oral Rehabilitation, 46(7), 666–690. https://doi.org/10.1111/joor.12801

Wetselaar, P., Vermaire, J. H., Lobbezoo, F., & Schuller, A. A. (2019). The prevalence of awake bruxism and sleep bruxism in the Dutch adult population. Journal of Oral Rehabilitation, 46(7), 617–623. https://doi.org/10.1111/joor.12787

Main image: Greg Pappas / Unsplash. Photos are illustrative stock images: they do not show patients, cases or results from The Special Teeth.

Educational information. A professional assessment determines the diagnosis and the appropriate options for each person.