Yes, a cavity can cause headaches. When decay reaches deep into a tooth, the nerve inside can become inflamed or infected, and that pain often spreads to the temples, jaw, ear or the area behind the eye. Treating the tooth usually eases the headache, so a dental exam is the fastest way to find out whether a tooth is behind the pain.
Many people put off the dentist, especially without dental insurance, hoping a small problem stays small. A cavity rarely does. Left untreated, it keeps growing toward the nerve, and the care it needs (and the cost) grows with it. Recurring headaches are one of the ways an untreated cavity makes itself known.
How a cavity leads to a headache
Your teeth, jaw and much of your face and head share the same major sensory nerve, the trigeminal nerve. When one branch is irritated, your brain can have trouble pinpointing the source, so pain that starts in a tooth can be felt somewhere else. Dentists call this referred pain.
A cavity usually causes headaches in a few stages:
- Decay reaches the inner layers of the tooth. Once it passes the enamel, the tooth may start reacting to hot, cold or sweet foods.
- The nerve becomes inflamed. When decay gets close to the pulp, the soft tissue that holds the nerve, it swells inside a space that cannot expand. That pressure can cause a deep, throbbing ache that travels into the head and jaw.
- Infection sets in. If bacteria reach the pulp, an abscess can form at the root. Without treatment, a tooth infection can spread to other parts of the body through the bloodstream, and your dentist and primary care doctor may both need to be involved.
- Your jaw tightens. Many people clench or chew on one side to protect a sore tooth. Tense jaw and temple muscles can add a tension headache on top of the tooth pain.
What a tooth-related headache feels like
Headaches that start with a tooth tend to share a few traits:
- The pain is on one side, usually the same side as the problem tooth.
- It sits in the temple, jaw, ear, cheek or behind the eye, often near the tooth.
- It feels dull and throbbing rather than sharp, and it may pulse with your heartbeat.
- It gets worse when you chew, bite down or drink something hot or cold.
- It may flare when you lie down, because more blood flows to the head and adds pressure inside an inflamed tooth.
Upper back teeth sit right below the sinuses, so a cavity there can feel like sinus pressure. It works the other way too: a sinus infection can make healthy upper teeth ache. An exam and X-rays sort out which one is going on.
How to tell if your headache is coming from a tooth
A tooth is more likely to be the cause when the headache comes with any of these:
- A tooth that is sensitive to temperature or sweets, or that lingers in pain after the trigger is gone
- Pain when you bite down on one spot
- A visible hole, dark spot or broken edge on a tooth
- Swollen or tender gums near one tooth, or a pimple-like bump on the gum
- A bad taste or smell that keeps coming back
- Headaches that started around the same time as tooth trouble
A cavity can also cause headaches with little or no tooth pain, especially when the pain is referred elsewhere or a nerve is starting to die. When a primary care doctor can’t find the cause of persistent headaches, a referral to a dentist is often the next step. A dental exam with X-rays can show decay, infection or cracks that you can’t see or feel.
Can a rotten, dead or broken tooth cause headaches?
Yes. The same nerve pathways are involved whatever the cause of the damage.
- A rotten or badly decayed tooth has decay that has reached, or nearly reached, the nerve. These teeth are the most common dental cause of headaches.
- A dead tooth may stop hurting for a while once the nerve dies, but the infection inside can still spread to the bone and gums and bring the pain back, sometimes with swelling.
- A cracked or broken tooth can let bacteria reach the nerve and can hurt sharply when you bite and release.
Any of these needs a dentist’s attention. The longer they wait, the fewer options there are for saving the tooth.
Can cavities cause migraines?
A cavity doesn’t cause migraine as a condition, but tooth pain can act as a trigger. Some people who get migraines notice attacks start or worsen when they have a toothache. The reverse also happens: migraine pain can be felt in the teeth and jaw. If your headaches change pattern, or come with tooth sensitivity, swelling or pain when you chew, it’s worth ruling out a dental cause.
Other dental problems that cause headaches
- Jaw clenching and teeth grinding. Many people clench or grind without realizing how much, often at night. Morning headaches, sore jaw muscles and worn teeth are common signs. Problems with the temporomandibular joint (TMJ) can cause headaches on their own, too.
- Gum infections. An abscess in the gums can cause throbbing pain that spreads much like a tooth infection. Early gum disease treatment keeps infection from reaching that point.
- Impacted wisdom teeth. Wisdom teeth that can’t come in fully can press on nearby teeth and irritate the gums and jaw, causing pain that travels toward the ear and temple. Learn more about wisdom teeth removal.
- A bite that doesn’t meet evenly. A high filling, a shifted tooth or missing teeth can strain the jaw muscles every time you chew.
How dentists treat a cavity headache
The headache eases when the source is treated. What that takes depends on how far the decay has gone:
- A filling repairs a cavity that hasn’t reached the nerve. This is the simplest fix, and the reason not to wait. See tooth fillings.
- A root canal treats a tooth whose nerve is inflamed or infected. It removes the damaged pulp, relieves the pressure and saves the natural tooth. See root canal treatment.
- An extraction is the answer when a tooth is too damaged to save. Learn about tooth extractions.
Your dentist will examine the tooth, take X-rays and talk you through the options before any treatment begins.
When a tooth headache is an emergency
Call a dentist the same day if you have:
- Swelling in your face, jaw or gums
- A fever along with tooth pain
- A bad taste or pus in your mouth
- Pain that keeps you up at night or doesn’t let up
Go to an emergency room or call 911 if swelling spreads toward your eye or neck, or if you have trouble breathing or swallowing.
South Sound Dental Care offers same-day emergency appointments during business hours, Monday through Friday. Call (253) 473-4303 and we’ll see you as soon as we can. Read more about emergency dental care and what an emergency visit costs.
Don’t ignore tooth and head pain
Persistent tooth and head pain rarely fixes itself. The problem usually grows, and so does the treatment it needs. If you think an untreated cavity or a jaw problem is behind your headaches, call us for an exam with Dr. Khan or Dr. Luce. They’ll find the source and plan the quickest way to relieve your pain. The best way to avoid cavity headaches altogether is cavity prevention: brushing, flossing and regular cleanings.
Cavity headache questions
Can a cavity cause a headache without tooth pain?
Yes. Pain from an inflamed tooth can be referred to your head, so you may feel the headache more than the tooth. A tooth whose nerve is dying can also hurt less while the infection continues. A dental exam with X-rays can find the problem.
Which side of my head will hurt?
Usually the same side as the problem tooth. Upper teeth tend to send pain toward the temple, cheek and eye, and lower teeth toward the jaw and ear.
Can a cavity cause jaw pain and headaches at the same time?
Yes. An infected tooth can make the jaw ache, and many people clench or chew on one side to protect a sore tooth, which strains the jaw muscles and adds a tension headache.
Will my headache go away after the tooth is treated?
If the tooth was the cause, the headache usually eases once the decay or infection is treated. If it doesn’t, your dentist can check for other causes, such as clenching, TMJ problems or a bite that doesn’t meet evenly.
Can a dead tooth cause headaches?
Yes. A dead tooth can stay infected, and that infection can cause pain and swelling that spread to the head and jaw, even if the tooth itself stopped hurting for a while.
Can tooth decay cause migraines?
Tooth decay doesn’t cause migraine as a condition, but dental pain can trigger attacks in people who already get migraines. Treating the tooth removes that trigger.
How long can a cavity headache last?
Until the tooth is treated. Pain from an inflamed tooth can come and go for days or weeks, and it often gets worse over time as the decay grows.
When should I see a dentist for a headache?
See a dentist if headaches come with tooth sensitivity, pain when chewing, swelling, a bad taste or a visible problem with a tooth, or if your doctor hasn’t found another cause. Call the same day if you have swelling or a fever.
