Sleep apnea and teeth grinding: how they're linked, and why your dentist may spot it first

Teeth grinding and sleep apnea often turn up in the same people. Researchers haven't proven that one causes the other, but the overlap is common enough that dentists are encouraged to ask about snoring and sleepiness when they see worn teeth. The link matters for treatment too, because a standard night guard isn't always the right choice for someone whose breathing stops at night.

Are teeth grinding and sleep apnea linked?

Teeth grinding during sleep, called sleep bruxism, and obstructive sleep apnea are linked in the sense that many people have both. Researchers still can't say whether sleep apnea causes grinding, grinding affects breathing, or both share a common trigger. The NHS lists snoring and sleep apnoea among the things teeth grinding is often linked to, alongside stress, anxiety, some medicines, smoking and a lot of alcohol or caffeine.

How often do they overlap? A 2024 narrative review in the Journal of Prosthodontics, written by dental sleep researchers in Montreal, Chile and Belgium, says sleep bruxism is reported by 8% to 12% of adults in the general population and 3% of older people. It cites studies from several countries in which 33% to 49.7% of people with obstructive sleep apnea also had sleep bruxism on sleep testing, even though the literature doesn't support a causal link between them.

If you want the basics on bruxism and jaw pain first, our article on mouth tape for teeth grinding and TMJ covers what sleep bruxism and TMD are. This article focuses on the apnea side.

What does the research show?

The research shows the two conditions often coexist, but the studies are small, mixed in quality and don't agree on how strong the link is. That's why we rate the evidence as limited.

The newest summary is a 2026 umbrella review in Sleep Medicine from researchers in Brazil. Instead of pooling individual studies, it looked at eight systematic reviews that used sleep-lab testing to diagnose apnea. Most of those reviews reported that bruxism and sleep apnea often occur together, possibly because of shared mechanisms such as micro-arousals (brief partial wake-ups) and activation of the nervous system. The authors concluded that adults with sleep apnea appear more likely to grind their teeth and that the link may run both ways. They also rated the methods of most of the reviews as low or critically low quality, and said randomized and long-term studies are needed.

Not every analysis agrees. A 2024 meta-analysis in Sleep Medicine Reviews pooled 14 studies and found the odds of bruxism in people with sleep apnea didn't differ from controls, whether the apnea was mild, moderate or severe. Its authors noted that most of the included studies were low quality, and said the results shouldn't stop clinicians from checking for both conditions.

The two findings fit together better than they first appear. The overlap is real in clinics, but whether apnea actually raises the risk of grinding, or both simply share triggers like poor sleep and frequent arousals, is still open.

The table sums up the small device and treatment studies covered below.

Does treating sleep apnea reduce grinding?

Treating sleep apnea reduced grinding in the studies that have looked, though the effect varies widely from person to person.

In the 2022 study from Wroclaw Medical University in Poland, 48 adults with sleep apnea had a full sleep study, then a second one while using either CPAP or a mandibular advancement device, a mouthpiece that holds the lower jaw forward. Bruxism measures fell significantly with both. CPAP did a better job of lowering the apnea-hypopnea index (AHI), but the two treatments didn't differ in how much they reduced grinding. The authors concluded that the risk of sleep apnea should be estimated in people who grind.

A 2023 pilot study from Amsterdam found something similar in 38 adults, 32 of them men. A marker of grinding called rhythmic masticatory muscle activity fell significantly with both CPAP and a mandibular advancement appliance. But it fell in only 60% of people, and the size of the change ranged widely. So treating apnea may quiet grinding for many people, not all.

Neither study had a randomized untreated comparison group, so some of the change could have other causes. If you're weighing apnea treatments, our guides to oral appliances for sleep apnea and getting used to CPAP explain both options.

Why might your dentist be the first to notice?

Your dentist may be the first to notice because grinding leaves marks a dentist can see. The NHS lists worn-down or broken teeth, a painful jaw, headaches and earache among the symptoms of teeth grinding.

The American Dental Association set out the dentist's role in a policy adopted by its House of Delegates in 2017. It says dentists are well positioned to identify patients at greater risk of sleep-related breathing disorders, and it encourages them to screen as part of a full medical and dental history. That screening covers symptoms such as daytime sleepiness, choking, snoring or witnessed pauses in breathing, plus risk factors including obesity, a set-back lower jaw (retrognathia) and high blood pressure. If a patient seems at risk, the ADA says they should be referred to a physician for proper diagnosis. Dentists screen and refer; they don't diagnose sleep apnea.

The 2024 Journal of Prosthodontics review recommends a similar approach for dentists treating grinding: use a screening questionnaire, check features such as jaw size, palate shape, tongue size and tonsils, and ask for a sleep test when in doubt. It says a home sleep test that records jaw-muscle activity along with breathing and oxygen may be used to confirm both conditions together.

So if your dentist asks how you sleep, how loudly you snore or whether you nod off in the day, that's why. Answer honestly. Our list of questions to ask your doctor about snoring can help you carry the conversation over to your GP.

Can a night guard make sleep apnea worse?

A standard night guard may make sleep apnea worse in some people, which is why it's worth checking for apnea first if you have any warning signs. The usual guard for grinding is a hard occlusal splint that covers the upper teeth. It protects them, but it doesn't hold the jaw forward the way an apnea mouthpiece does.

In the 2004 pilot study from the University of Montreal, 10 people with sleep apnea spent one night in a sleep lab with a splint and one without. Average AHI didn't change significantly across the group, but AHI rose by more than 50% in 5 of the 10, four moved into a worse apnea severity category, and time spent snoring went up by 40%. The authors suggested clinicians ask about snoring and sleep apnea before recommending a splint.

A 2013 randomized crossover trial in the Netherlands tested this more carefully, again in 10 people, over three nights with a splint and three without. Average AHI was slightly higher with the splint, 17.4 versus 15.9 events per hour. The authors said the splint carries a risk of making apnea worse but that the effect was small, which limits how much it matters in practice.

The 2024 Journal of Prosthodontics review, which pulls this work together, recommends that when someone has both bruxism and confirmed sleep apnea, dentists consider a mandibular advancement device instead of a standard splint. It also flags that some medicines used for grinding, including clonazepam, carry a risk of raising AHI and causing sleepiness.

None of this means you should stop wearing a guard your dentist fitted. It means your dentist should know if you snore loudly or have apnea symptoms, so they can choose the right device. Our article on snoring mouthpiece side effects covers what to expect from jaw-advancing devices.

What else can help with grinding?

Other steps can ease grinding alongside any apnea care. The NHS suggests finding ways to relax, keeping a regular bedtime in a dark, quiet room, having regular dental check-ups, and not smoking or drinking too much alcohol or caffeine. For jaw pain it suggests painkillers like ibuprofen or paracetamol and an ice pack wrapped in a tea towel for 20 to 30 minutes. It also says treatment for teeth grinding is not always needed.

Alcohol is worth a closer look if you have both problems, since it can also worsen breathing during sleep. We cover that in sleep apnea and alcohol. The NHS also notes that some medicines for sleep problems, depression or anxiety are linked to grinding, so if you've started a new medicine, mention it to your doctor rather than stopping it yourself.

When should you see a doctor or dentist?

See a dentist if you grind and have tooth damage, sensitive teeth or pain in your jaw, face or ear, or if a partner says you grind in your sleep. That's the NHS's advice.

See a doctor about your sleep if grinding comes with any sign of sleep apnea. The NHS lists breathing that stops and starts, gasping, snorting or choking noises, waking up a lot, loud snoring, feeling very tired in the day, trouble concentrating, mood swings and morning headaches. Morning headaches and poor sleep can come from grinding too, which is one reason the two are easy to confuse. Our guides to sleep apnea warning signs and the home sleep apnea test explain what happens next.

A nose that's always blocked is worth raising too, since it changes how you breathe at night. If you're pregnant and notice new snoring or grinding, ask your midwife or doctor before trying any new device.

This article is general information, not medical advice. Talk to your doctor or dentist about your own symptoms.

Read next

• Mouth breathing and your teeth
• Snoring vs. sleep apnea: how to tell the difference
• Sleep apnea treatment options

* This content is for informational and educational purposes only and is not medical advice. It is not intended to diagnose, treat, cure or prevent any disease or health condition. Talk to a qualified healthcare provider about your health.