Sleep Apnea and Teeth Grinding (Bruxism)

Teeth grinding includes clenching your teeth, and is also called bruxism. While this generally happens during sleep, it also can occur during daytime. 

While people may ignore their teeth grinding, left untreated it can cause damage to the teeth, as the constant grinding and clenching wears away at the enamel. 

Symptoms of teeth grinding include:

  • Clicking or popping sounds when moving the jaw
  • Jaw or neck pain from the additional stresses caused by bruxism
  • Morning headaches
  • Teeth becoming more sensitive to hot and cold temperatures
  • Injury to the tongue, lips or cheeks

How Are Teeth Grinding and Sleep Apnea Connected?

Studies indicate between 33% to 54% of people who experience obstructive sleep apnea (OSA) also grind their teeth. 

OSA is the most common form of the disorder sleep apnea. It is characterized by narrowing airways that obstruct oxygen flow to the lungs. People with OSA can experience frequent micro-arousals from sleep as the brain prompts the body to awake for air. This results in excessive daytime fatigue.

A recent study in Europe of 13,000 people also reported that those who grind their teeth at night have higher rates of OSA. This study found one in ten respondents grind or clench their teeth during the night on a weekly basis. 

While anxiety, stress and family history are contributing risk factors for teeth grinding, OSA is also seen as having a potential link to sleep bruxism.

The Possible Links Between Teeth Grinding and Sleep Apnea

More research is required on the potential link between the two disorders. 

However, the fact that several studies have reported a higher-than-expected incidence where people have both OSA and teeth grinding suggests a potential connection. Such results have come from studies involving polysomnography, where sleeping patterns are closely monitored to produce a more in-depth sleep study.

While these studies may point to a link between the two conditions, no direct causal connection has yet to be established. There is not a consistent pattern to when the teeth grinding may occur during the night. This could suggest that the two disorders happen independently of one another or are affected by a further, as yet unidentified, influence.

OSA as a Contributing Risk Factor for Teeth Grinding

One prime theory is that the micro-arousals caused by OSA cause sleep bruxism. When blood-oxygen levels drop as the airways become blocked, the body is prompted to wake in order to breathe. This could result in a movement of the jaws that leads to sleep bruxism.

As the body awakens, the nervous system could also be producing sudden movements which may increase the risk of teeth grinding. Again, it must be stressed that more research is required. 

However, as severe OSA can see up to 30 micro-arousals an hour, some researchers suggest that the greater the severity of someone’s sleep apnea the greater the chance they could experience sleep bruxism.

Could Teeth Grinding Increase the Risk of Sleep Apnea?

While micro-arousals tend to occur before a teeth grinding episode, it is not always the case. This is why some researchers feel that the two disorders may occur independently from the other. Also, not everyone who has sleep apnea experiences teeth grinding -- and not everyone with teeth grinding has sleep apnea.

Some early research has pointed to neurotransmitters such as serotonin and dopamine as being underlying influences in the development of these two disorders.

Treatment for Sleep Apnea and Teeth Grinding

The main treatments to address sleep apnea may have a beneficial effect in treating teeth grinding too. 

CPAP is a leading treatment for OSA, delivering pressurized air through a mask worn overnight to keep the airways open. Keeping the airways open prevents the micro-arousals, which may then remove the factor initiating the night-time teeth grinding.

A custom-made mouthpiece is another way your doctor, dentist or sleep specialist could address your OSA. 

It’s called a Mandibular Advancement Device (MAD), and is designed to hold the tongue down and position the jaw forward. As with CPAP, this device helps keep the airways clear to prevent the frequent awakenings overnight caused by blocked airways.  It is important to locate a dentist with advanced sleep training as dentists are the only professionals who can recommend and make the necessary adjustments to a MAD device.

A custom-made mouthpiece also helps protect the teeth from teeth grinding and is the best option if you have sleep apnea. Those who have bruxism alone might use a bite splint instead, which fits over some or all your teeth.  Lifestyle changes can also be important, helping to encourage sleep and to stay asleep, preventing micro-arousals which may not even be associated with OSA. These can include:

  • Reduce anxiety and stress
  • Quit Smoking
  • No alcohol or caffeine in hours before bed
  • Exercise, although not too close to bedtime
  • Relaxation techniques before bed
  • Ensure bedroom optimized for sleep

While there is a high incidence where people experience both sleep apnea and teeth grinding, more research is required to see if there is a connection between the disorders. Diagnosis and treatment are key to reducing the impact of both.

Sources:

https://www.webmd.com/sleep-disorders/sleep-apnea/news/20010124/are-you-grinding-your-way-to-sleep-apnea 

https://www.sleepapnea.org/sleep-health/teeth-grinding-and-sleep-apnea/ 

https://www.sleepfoundation.org/sleep-apnea/link-between-sleep-apnea-and-teeth-grinding 

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6832407/