Can a Root Canal Cause a Sinus Infection?

November 11, 2025

If you’ve recently had a root canal and are now noticing the signs of a sinus infection, you might be wondering if the two are connected.

There’s lots of anecdotal evidence online with many people experiencing this issue. It almost seems too common to be a coincidence.

Well, it’s usually not a coincidence, but it’s a bit more complicated than first meets the eye.

Root Canals Don’t Cause Sinus Infections - Tooth Infections Do

Root canals are a procedure used to treat a badly infected tooth. By this point, the bacteria causing the infection has reached the narrow chambers of the tooth.

The thing is, bacteria can actually spread to other tissues as well. If one of your upper teeth was infected for a long time, it’s possible the infection has spread to the sinuses; you didn’t show any symptoms until after your root canal.

If that’s the case, you might need antibiotics and decongestants to treat your infection. Speak to your primary care doctor to get the proper treatment.

But, Root Canals Can Make It Look Like You Have a Sinus Infection

To treat a badly infected tooth, a dentist will use special tools to clean the very narrow chambers of the root, which are very close to the sinuses. Sometimes, the dentist can push a bit too hard and accidentally cause a small tear in the sinus lining.

This causes something called “sinus communication”, which can present with sinusitis-like symptoms. The good news is that this condition goes away on its own in just a few days after the sinus lining heals.

If it lasts longer, then the tear might be bigger, in which case you should reach out to your dentist for another appointment.

And Sometimes, It’s Just a Coincidence

Sometimes you can experience two health conditions at roughly the same time, and they might not be connected at all.

In the case of root canals and sinus infections, if your infected tooth was on the lower jaw, then you can most likely count it as a coincidence. Your sinuses are near your upper teeth, so there is no chance of sinus communication post root canal when treating lower teeth.

Plus, a lower tooth infection will usually travel down, and affect the jaw bone, not the sinuses.

Need a Root Canal? We Can Help

We know root canals in Farragut can sound like a scary procedure, but they’re also the best way to treat a badly infected tooth and potentially prevent a permanent extraction.

Dr. Luis and Dr. Tori Mariusso are here to help you access expert oral care that can remove your discomfort and restore your oral health.

If you’re dealing with high levels of pain and can’t wait for a regular appointment, call us at (865) 248-2312 for an emergency root canal.

Or, you can request a visit online.

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