Why Do I Bite My Tongue in My Sleep? Causes & How to Stop It

What happens when you bite your tongue in your sleep?

The tongue is highly mobile and sensitive. During normal sleep, it continuously changes position as you breathe, swallow and move your jaw. If the jaw closes while part of the tongue is between the teeth, the biting surfaces can pinch, scrape or cut the tissue.

A minor injury may leave a tender spot or small indentation along the side of the tongue. A more forceful bite can cause swelling, bleeding, a deeper laceration or an ulcer that becomes irritated each time it touches the teeth.

The injury itself can create a frustrating cycle. Swollen tissue occupies more space and may be easier to catch between the teeth again. Repeated trauma can then prevent the area from healing fully.

Common causes of tongue biting during sleep

There is no single explanation that applies to everyone. Nighttime tongue biting is a symptom, not a diagnosis. The pattern, severity and accompanying symptoms help a dentist, physician, sleep specialist or neurologist determine what may be happening.

Is teeth grinding causing you to bite your tongue?

It is possible. Sleep bruxism involves jaw-muscle activity during sleep that may include grinding, clenching or jaw thrusting. If the tongue moves between the dental arches during one of these movements, it can become pinched or cut.

However, waking with a bitten tongue does not prove that you grind your teeth. Some people have bruxism without injuring their tongue, and some people experience tongue biting because of a different type of sleep-related movement.

Signs that bruxism may also be present

• Flattened, chipped or increasingly sensitive teeth
• Jaw tension or fatigue upon waking
• Dull morning headaches, particularly near the temples
• Damage to fillings, crowns, bonding or veneers
• Grinding, tapping or clicking sounds heard by another person
• Ridged or scalloped impressions along the sides of the tongue
• Recurring trauma to the inner cheeks

Tongue biting and cheek biting often overlap because both tissues can become caught between moving teeth. Our guide to the best mouth guard for cheek biting explains why standard one-arch night guards may not provide complete soft-tissue coverage.

A dentist can look for tooth wear, cracks, muscle tenderness and changes in your bite. In uncertain or complex cases, an overnight sleep study with video and physiological monitoring may be more informative than symptoms alone.

Is tongue biting a sign of sleep apnea?

Tongue biting by itself is not considered a reliable diagnostic sign of obstructive sleep apnea. Research does, however, show an association between obstructive sleep apnea and sleep bruxism in some patients. Both can occur around brief sleep arousals and changes in nervous-system activity.

That relationship does not mean one condition always causes the other. It means that a person with repeated jaw activity—especially alongside snoring or disrupted breathing—may benefit from a broader sleep evaluation.

Ask about sleep apnea screening if you also experience:

• Loud, habitual snoring
• Gasping, choking or abrupt awakenings
• Breathing pauses witnessed by another person
• Morning headaches or dry mouth
• Unrefreshing sleep despite enough time in bed
• Significant daytime sleepiness or impaired concentration
• High blood pressure or other recognized sleep-apnea risk factors

Could nighttime tongue biting be related to seizures?

In some cases, yes. Tongue biting—particularly a significant injury along the side of the tongue—can occur during a seizure. But tongue injuries can also result from bruxism and less common sleep-related movement disorders, so the location of a bite cannot provide a diagnosis by itself.

Nocturnal seizures may be difficult to recognize because they happen while the person is asleep. A bed partner may notice unusual stiffening, repetitive movements, vocalizations or a sudden disturbance. The person may wake with confusion, muscle soreness, a headache, unexplained injuries or evidence of lost bladder control.

Sleep-related facial mandibular myoclonus is another uncommon cause described in medical literature. It can produce repeated jaw movements and tongue biting during sleep and may initially be mistaken for either epilepsy or bruxism. Distinguishing between these conditions can require a neurological assessment and combined video, EEG or muscle monitoring.

How to care for a bitten tongue

Many small tongue injuries heal without extensive treatment. The goal is to keep the area clean, reduce swelling and avoid repeatedly irritating it.

For a minor tongue bite

1. Rinse your mouth gently with clean water.
2. Apply light pressure with clean gauze if the area is bleeding.
3. Use a cold compress externally or allow small ice chips to melt in the mouth.
4. Choose soft, cool foods while the area is tender.
5. Avoid spicy, acidic, very salty or sharp foods that sting or reopen the injury.
6. Keep up with gentle oral hygiene while avoiding direct scrubbing of the wound.

Avoid placing aspirin directly on oral tissue. Use over-the-counter pain relief only when it is safe for you and according to the product directions or advice from your healthcare professional.

Contact a dentist or healthcare professional if:

• Bleeding does not stop with direct pressure
• The cut is deep, gaping or extends through the tongue
• Swelling interferes with swallowing or breathing
• Pain, redness or swelling is getting worse rather than better
• You develop fever, drainage or another sign of infection
• The sore does not heal or keeps returning
• A sharp tooth, broken restoration or dental appliance is causing trauma

Can a mouth guard stop tongue biting during sleep?

A protective oral appliance may help when the immediate problem is repeated contact between the teeth and soft tissue. Covering sharp biting surfaces with smooth material can make it harder for the teeth to grip, pinch or cut the tongue and inner cheeks.

This is best understood as mechanical protection. A guard may protect the injured area and give it an opportunity to heal, but it does not necessarily stop the jaw movement that caused the bite. It also does not treat seizures, sleep apnea or another underlying medical condition.

Why an ordinary night guard may not be enough

Most conventional night guards are designed primarily to protect teeth from grinding. They usually cover one dental arch—either the upper teeth or the lower teeth.

That may be appropriate for tooth protection, but tongue and cheek biting is different. When one arch remains uncovered, its natural biting edges can still come into contact with the tongue or cheek. The exposed teeth may continue to catch soft tissue during side-to-side or closing movements.

People who primarily need protection from tooth wear should discuss an appropriate traditional night guard with their dentist. People whose main concern is soft-tissue injury may need protection designed specifically for both dental arches.

Upper and lower guards vs. a standard night guard

How do the two guards protect the tongue and cheeks?

Each appliance covers the natural edges and contours of one dental arch. When both are worn, the tongue and inner cheeks encounter smooth guard material rather than exposed upper or lower biting surfaces.

The goal is not to hold the tongue in a rigid position. The tongue still needs room to move naturally for breathing and swallowing. Instead, the appliances create a protective interface around the teeth so that involuntary jaw contact is less likely to produce another sharp injury.

How a custom tongue and cheek biting guard set is made

A custom appliance begins with an accurate model of your upper and lower teeth. Sentinel can work from at-home dental impressions or compatible digital dental files supplied by a dentist or dental office.

The at-home impression option

The kit is used to capture the shape of both the upper and lower teeth. The impressions are returned to the lab, reviewed for accuracy and used to fabricate the coordinated guard set.

What happens in the lab?

1. The upper and lower impressions or digital files are reviewed for usable detail.
2. Working models are created to reproduce the person’s dental anatomy.
3. Dental material is formed over each model.
4. Each appliance is trimmed by hand to follow the gumline and tooth contours.
5. The edges are smoothed and polished for a more comfortable finish.
6. The completed upper and lower guards are inspected before shipment.

For a closer look at laboratory fabrication, read how custom mouth guards are made. Although materials and designs vary by product, the article explains how dental models are created and how appliances are formed, trimmed and hand-finished.

Using an STL or PLY dental scan

Some dental offices can provide digital scans of the teeth instead of physical impressions. An STL file is a three-dimensional surface file commonly exported by intraoral scanning systems. A PLY file is another compatible three-dimensional format.

The scan must accurately capture both arches and should reflect the current position of the teeth. Files from an old scan may not be appropriate if you have since had dental work, orthodontic movement, extractions or other significant changes.

Our step-by-step STL ordering guide explains how to request a scan from a dental office and submit the file for fabrication.

How to reduce the risk of biting your tongue again

The most effective plan depends on why the biting is happening. Protecting the tissue may be one part of the solution, but persistent symptoms may require dental, medical, neurological or sleep-focused care.

1. Arrange a dental examination

A dentist can check for sharp teeth, fractured restorations, changes in your bite, signs of grinding and areas where the tongue or cheek repeatedly contacts the teeth.

2. Keep a symptom record

Note when injuries occur, where they appear and whether you experienced headaches, jaw soreness, unusual movements, poor sleep, breathing symptoms or confusion. Photographs of the injury may also help a clinician identify patterns.

3. Ask a partner what they observe

Grinding sounds, repeated jaw movements, gasping, stiffening, jerking or unusual vocalizations can provide important context. A short recording may be useful to a healthcare professional when it can be obtained safely and respectfully.

4. Review medication changes

Tell the prescribing clinician if symptoms began after starting a medication or changing its dose. Do not discontinue prescription medication on your own.

5. Address sleep quality

Maintain a consistent sleep schedule, give yourself adequate sleep time and discuss chronic snoring or breathing interruptions with a professional. Reducing late-day caffeine and heavy alcohol intake may also improve sleep quality for some people.

6. Reduce daytime jaw tension

When you are not eating or swallowing, the teeth generally do not need to be pressed together. Periodic reminders to relax the jaw may help people who also clench while awake, although daytime habit changes may not eliminate involuntary movement during sleep.

7. Protect healing tissue when appropriate

When repeated contact with the teeth is preventing healing, a properly fitted protective appliance may reduce reinjury. The design should match the actual problem: a traditional night guard for tooth protection, or an upper-and-lower set when both arches must be covered to protect the tongue and cheeks.

Who should not use an at-home impression kit?

Do not use an at-home dental impression system if you have active braces, loose teeth, loose dental work or another condition that makes taking an impression unsafe. Contact Sentinel before ordering if you are uncertain.

A custom guard also needs to reflect your current dental anatomy. New dental work, ongoing orthodontic movement or recent tooth loss may require updated impressions or scans.

A protective appliance should feel secure but not painfully tight. Stop wearing it and contact the provider if you develop persistent tooth pain, lasting pressure, gum injury, an altered bite or another concerning change.

Frequently asked questions