Waking up tired, sensitive teeth or tight jaw muscles could signify that you grind or clench your teeth during sleep. This condition is known as bruxism.
If left untreated, bruxism can lead to:
Health issues linked to bruxism include stress and teeth misalignment. However, one of the primary risk factors is a severe condition called obstructive sleep apnea (OSA). Obstructive sleep apnea occurs when your throat muscles relax when you are asleep. This blocks the airways and interrupts regular breathing.
In many cases, breathing disorders (such as sleep apnea) are diagnosed by dentists rather than doctors.
While bruxism can occur at any time of the day, it often happens during sleep. This is called sleep bruxism. Sleep bruxism can cause people to awaken feeling tired and unrefreshed, sometimes with headaches or neck and jaw pain.
Sleep bruxism can often go unnoticed by the individual. The condition can be picked up if a partner complains about the noise teeth grinding can make. Or it can also be discovered during a dental exam.
Dentists often identify underlying issues with sleep bruxism. Sometimes the disorder results from a misalignment of the teeth or jaw, for example. A dentist may find evidence of bruxism during one of your checkups or teeth cleaning appointments.
Evidence of sleep bruxism may include:
While sleep bruxism is an oral health issue, it is also considered a sleep-related movement disorder. Sleep bruxism is characterized by uncontrolled and involuntary physical movements during the night.
If your dentist notices issues with your teeth that suggest bruxism, they may check your blood pressure levels and ask you about the following issues:
Individuals with undiagnosed and untreated sleep apnea may experience some of the above issues. These patients are also known to grind their teeth or clench their jaws at night.
Around a quarter of all people experiencing obstructive sleep apnea also have sleep bruxism. While it’s still unclear why the two disorders are linked, researchers believe that arousal resulting from upper airway resistance leads to a stress response throughout the body.
Once awoken from sleep apnea, the heart and respiratory rates increase along with stress hormones. This stress response promotes increased jaw muscle activity, leading to clenching or grinding of the teeth.
Another theory is that during an episode of snoring, or even a partial obstruction (hypopnea), the tissues along the upper airway collapse. This collapse leads to airway instability. Airway instability may signal the jaw to tighten its muscles to harden the softer sides of the throat.
Bruxism may also be the body’s reaction to another medical condition, like gastroesophageal reflux disease (GERD). GERD is also linked to sleep apnea.
Also known as acid reflux or heartburn, GERD arises when stomach contents break the valve at the lower esophagus and spill into the throat. The high-acid substances can damage the tissues of the upper airway. The brain may indicate the jaw muscles to stiffen to create a barrier.
Your personality and individual habits can affect your risk of developing bruxism and sleep apnea.
People who are motivated and driven often have a higher rate of bruxism and sleep apnea. Bruxism and sleep apnea can also result from stress and anxiety. This may be from a life event or pressure at work or school.
Smoking cigarettes or drinking caffeine before sleeping may also increase tooth grinding. Secondary sleep-related bruxism is often experienced by children with cerebral palsy and those who are developmentally disabled.
There may be other risk factors that lead to bruxism and sleep apnea. Common causes include:
Until future research reveals the precise nature of the relationship between sleep apnea and sleep bruxism, it is difficult to know whether the link is clinically important.
In the meantime, those who have obstructive sleep apnea or sleep-related bruxism should understand that they may occur together. This can help them identify symptoms and address the issue with their doctor, who can assess whether further testing or treatment would be helpful.
When both conditions are present, awareness of them may play a role in optimizing treatment.
Managing sleep apnea can help prevent nighttime teeth grinding and clenching. Lifestyle adjustments, such as losing weight and quitting smoking, can help, as can assisting nasal allergies.
Additionally, your doctor may suggest using a dental guard or an oral splint to avoid damaging the teeth caused by grinding and clenching.
For moderate to severe sleep apnea, a continuous positive airway pressure device (CPAP) is used. This medical device sits over your nose when sleeping and keeps the airway passages open using air pressure. The CPAP machine helps to prevent sleep apnea and snoring, which usually co-occurs with the disorder.
When patients with bruxism and sleep apnea use a CPAP oral appliance, their breathing issues improves significantly, and teeth grinding often stops completely.
Whether you’re experiencing symptoms of teeth grinding, sleep apnea, or both, discussing treatment options with your doctor can help you address your sleep health issues.
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