Sinus toothache or dental toothache? How to tell the difference

What’s probably going on

Your upper back teeth sit right under your maxillary sinuses, the air spaces behind your cheekbones. The roots of the upper molars are close to the sinus floor. When the sinuses swell and fill during a cold, allergies or a sinus infection, the pressure can irritate the nerves of those teeth. Cleveland Clinic notes that sinus pressure commonly radiates to the upper molars.

So a sore upper tooth during a cold is often the sinus, not the tooth. But not always, and the two can look alike.

Signs it’s more likely your sinuses

• Several upper teeth ache at once, usually the back ones, on one or both sides. It feels like a heavy, dull pressure more than a sharp pain.
• You have sinus symptoms too: a stuffy or runny nose, thick drainage, pressure around your eyes or cheeks, or a headache.
• It’s worse when you move your head. Bending forward or lying down can make it throb.
• It started with a cold or allergy flare, and it eases as your nose clears.
• Your lower teeth feel fine. The maxillary sinuses sit above the upper teeth, so sinus-related tooth pain usually centers on the upper back teeth. Pain in a lower tooth points more toward the tooth itself.

Signs it’s more likely the tooth

• You can point to one tooth. A toothache is usually in a single tooth.
• Hot, cold or sweets set it off, especially pain that lingers after the cold is gone. See tooth sensitive to cold and tooth sensitive to heat.
• It hurts when you bite on one spot. See tooth hurts when biting.
• The gum near it is swollen, or there’s a bump, a bad taste or a bad smell. See tooth abscess.
• It throbs on its own, or it wakes you up. See toothache at night.
• You have no cold, no allergies and no stuffy nose.

It can also run the other way

A tooth can cause a sinus infection. The American Association of Endodontists says studies show more than 40% of maxillary sinus infections start from a tooth, rising to over 70% when the infection is on only one side. These teeth often don’t hurt to hot, cold or tapping, because the nerve inside has already died or an old root canal is failing. If you keep getting sinus infections on the same side, ask a dentist to check your upper teeth.

What to do tonight

If it feels like sinus pressure, treat the sinuses and watch the tooth.

1. Rinse your nose with saline. A saline spray, squeeze bottle or neti pot can clear mucus and ease the pressure. The FDA says to use distilled or sterile water, tap water boiled for 3 to 5 minutes and cooled to lukewarm, or water run through a filter made to trap germs. Never use water straight from the tap.
2. Breathe in steam. A hot shower or a bowl of steaming water can help open things up.
3. Sleep with your head raised. An extra pillow helps drainage.
4. Take an over-the-counter pain reliever as the label directs. Ibuprofen can help both sinus pain and tooth pain. Ask a pharmacist first if you take other medicines, are pregnant, or have stomach, kidney or bleeding problems.
5. Go easy on decongestant sprays. Use them only as long as the label allows, usually no more than three days. Longer use can make stuffiness worse.
6. Drink plenty of fluids.

If it feels like the tooth, follow what to do for a toothache right now.

What not to do

• Don’t put heat on a swollen face. Facial swelling isn’t sinus pressure; it can be an infection. Call a dentist.
• Don’t take leftover antibiotics. Many sinus infections clear on their own within about 10 days, and antibiotics don’t fix a tooth.
• Don’t wait weeks on tooth pain because you assume it’s your sinuses.

Dentist or doctor?

See a doctor if your sinus symptoms last longer than 10 days, keep coming back, or worry you.

See a dentist if:

• The pain is in one tooth, or hot and cold set it off
• The tooth pain outlasts your stuffy nose
• Your gum is swollen or you have a bump on it
• You keep getting sinus infections on one side

Get emergency care for a fever over 103°F, changes in your vision (especially with pain or swelling around your eye), confusion, a seizure, or a stiff neck. Cleveland Clinic lists these as reasons to get help right away with a sinus infection.

How a dentist tells, and what it costs

A dentist will ask about your symptoms, look at the teeth, tap them and often test them with cold. An X-ray shows whether there’s a deep cavity or an infection at the root. If the teeth look healthy, the dentist may send you back to your doctor to treat the sinuses.

If the tooth is the cause, the fix might be a filling, a root canal or an extraction. The AAE says that when a tooth is causing a sinus infection, antibiotics and sinus treatment alone usually won’t clear it; the tooth has to be treated. The price depends on the treatment, so ask for a written estimate first. See root canal cost, or try the dental cost estimator. If you don’t have insurance, a dental savings plan (a discount membership, not insurance) can lower the bill at participating dentists.

How to keep it from coming back

• Treat allergies and colds early, so your sinuses don’t stay blocked for days.
• Brush twice a day with fluoride toothpaste and clean between your teeth daily. A healthy tooth is less likely to be the real cause next time.
• Keep up with checkups. Dead or failing teeth that seed sinus infections often don’t hurt, and a dentist can spot them on an X-ray.
• If the same side keeps getting sinus infections, tell both your doctor and your dentist.