Teeth grinding (bruxism): causes, symptoms and treatment

What is bruxism?

A 2018 international consensus report defines two forms: sleep bruxism, which is jaw-muscle activity during sleep, and awake bruxism, which involves repeated or sustained tooth contact, clenching, or bracing and thrusting of the lower jaw while awake.

The same report concludes that in otherwise healthy people bruxism should be seen as a behaviour that may be a risk factor for certain consequences, such as tooth wear or muscle pain, rather than a disease in itself. Assessment therefore focuses on its effects.

How common is it?

A 2013 systematic review of adult studies, based mainly on self-report questionnaires, found awake bruxism in roughly 22–31% of people and frequent sleep bruxism in about 13%. Bruxism was not linked to sex and appeared to decrease in older age.

The authors caution that these figures are uncertain: many people who grind their teeth at night are unaware of it until a partner or dentist notices.

Symptoms to look out for

The NHS notes that jaw pain from grinding can develop into a temporomandibular disorder (TMD) affecting the jaw joint.

• Jaw, face or temple pain or stiffness, often worse in the morning
• Worn, flattened, chipped or cracked teeth
• Increased tooth sensitivity
• Headaches or earache
• Disrupted sleep, or a partner hearing grinding at night

What causes teeth grinding?

The exact cause is not always clear. The NHS lists stress and anxiety as the most common triggers. Sleep problems such as snoring and sleep apnoea, some medicines for sleep, depression or anxiety, smoking, and drinking a lot of alcohol or caffeine are also linked to bruxism.

If you have signs of sleep apnoea — loud snoring, pauses in breathing or heavy daytime sleepiness — it is worth discussing these with a doctor as well as your dentist.

Treatment: what does a night guard do?

Not everyone who grinds needs treatment. When there is tooth damage, sensitivity or jaw pain, a dentist may make a custom splint (night guard) from an impression or digital scan, to be worn while sleeping. Its main purpose is to protect the teeth from wear.

A 2007 Cochrane review found insufficient evidence that occlusal splints reduce sleep bruxism itself, although they may help with regard to tooth wear. Splints are therefore usually combined with stress management and good sleep habits.

If you grind your teeth and are considering fillings, zirconia crowns, porcelain veneers or dental implants, your dentist will take biting forces into account when planning and may recommend a protective splint afterwards.

Self-help tips

For pain or swelling, the NHS suggests over-the-counter painkillers or an ice pack wrapped in a towel. A GP can help with underlying issues such as stress, anxiety or sleep problems.

• Relaxation: breathing exercises, regular physical activity or music
• Regular bedtimes and a dark, quiet bedroom
• Stop smoking and cut down on alcohol and caffeine
• Avoid chewing gum and hard foods while your jaw is sore
• Notice daytime clenching: at rest, lips together and teeth slightly apart

Practical notes if you are travelling for dental treatment

Tell the dentist during your assessment if you grind or clench your teeth, or if your partner has noticed it — it can change the treatment plan and the choice of materials. A custom night guard needs an impression or scan and a laboratory step, so ask the clinic how many days to allow for fitting before you book your return flight, and bring any existing guard with you.

Frequently asked questions