Can a Sinus Infection Make Your Teeth Hurt? Sinus vs Tooth
Clinically reviewed by Dr. Abinaash Kaur, DDS, RCDSO, on 2026-10-26. Dr. Kaur is a general dentist in Toronto (Bloor West Village) registered with the Royal College of Dental Surgeons of Ontario.
Yes. The roots of your upper back teeth sit right under the floor of your sinuses, so a congested or infected sinus can make several upper teeth ache at the same time. The pattern is the giveaway: sinus pain spreads across a few teeth and comes with a stuffy nose, while a tooth problem usually picks one tooth and reacts to cold, sweets or biting.
Physicians know this one well. A Canadian guide to acute sinusitis published in CMAJ lists an ache in the upper teeth as one of the five best predictors of a bacterial sinus infection (CMAJ), and the journal's 2025 review of long-running sinus inflammation counts dental pain among its additional symptoms (CMAJ).
Here's how I sort it out in the chair, what to do while you wait, and when the right person to see is a physician rather than a dentist.
Why would a sinus infection make your teeth hurt?
Your maxillary sinuses are two air-filled spaces in your cheekbones, one on each side of your nose. The floor of each one sits just above the roots of your upper back teeth, and in some people the roots reach up into it.
When the lining of the sinus swells with a cold or an infection, the pressure pushes on those roots and the nerves that serve them. The teeth aren't sick, but they hurt. Of all the sinuses, the maxillary ones are the most commonly affected (Government of Canada), and the CMAJ guide notes that about 90% of sinusitis cases involve them (CMAJ). That's why it's the upper teeth, not the lower ones, that complain.
The molars take the brunt. A study of dental 3D scans found the upper first and second molars were 11 times more likely to be involved in sinus-related changes than the premolars in front of them (Journal of Endodontics via PubMed).
Pretty much every winter, someone sits in my chair convinced a molar is dying, and it's a cold.
Is it your sinus or your tooth?
Most people think a toothache is a toothache. Here's what I ask before I pick up a single instrument.
| What you notice | Points to the sinus | Points to a tooth |
|---|---|---|
| How many teeth hurt | Several upper back teeth at once, often on both sides | One tooth you can point to |
| What the pain feels like | Dull pressure or fullness in the cheek and teeth | Sharp, throbbing, or a jolt when you bite |
| What sets it off | Bending forward, lying down, a bumpy car ride | Cold, sweet, heat, or chewing on that one tooth |
| What came with it | A stuffy nose, coloured discharge, a cold in the past week | Nothing else; the tooth hurts on its own |
| Where it sits | Across a group of teeth, hard to pinpoint | One spot, easy to pinpoint |
A tooth that zings with cold and settles within seconds is behaving like a sensitive tooth, not a sinus. Our post on why teeth get suddenly sensitive runs through that list, and the one on sensitivity causes and treatment covers the fixes.
Pain that wakes you at 2am is a weaker clue than people think. A sinus ache does get worse lying flat, but so does an inflamed nerve, so I never lean on that one alone. Our post on why toothaches get worse at night walks through the difference.
What gives when the pain is only on one side?
One side alone doesn't settle it. The CMAJ guide names facial pain, "particularly unilateral", meaning on one side, among the findings that make sinusitis more likely (CMAJ). Sinuses come in pairs, and a cold can block one more than the other.
A single tooth on one side, with no congestion, is usually a tooth. A sinus infection that camps on one side for weeks, especially with a bad smell or taste, makes me look harder at the teeth above it, for a reason that surprises most people.
Can a bad tooth cause a sinus infection?
Yes, and it's the part almost nobody has heard of. The infection travels upward from the root of a dead or abscessed upper tooth into the sinus above it. Dentists call this odontogenic sinusitis (a sinus infection that starts from a tooth).
The CMAJ guide puts dental root infection behind 5% to 10% of bacterial maxillary sinusitis cases, and advises physicians to tap the upper teeth to check for tenderness (CMAJ). Newer work puts the number higher. A case series from an ear-nose-and-throat clinic and a root canal practice noted published rates from 10% to 40% of bacterial sinusitis, and found that only 39% of the dental-origin cases had an upper toothache at all (International Forum of Allergy and Rhinology via PubMed).
That's the trap. The tooth that started the infection often doesn't hurt.
In another series, dental pain was present in fewer than half of the patients, symptoms had run for an average of 2.6 years, and the dental cause was missed on most of the plain dental x-rays taken before a CT scan (International Forum of Allergy and Rhinology via PubMed). A 2022 review found oral antibiotics are generally ineffective at resolving a tooth-driven sinus infection, that it most commonly shows up on one side, and that when both the tooth and the sinus are treated, resolution can be expected in 90% to 100% of cases (World Journal of Otorhinolaryngology via PubMed).
Did you know about this? Most people don't, which is why a sinus infection that keeps coming back on one side deserves a dental x-ray. CMAJ's 2025 review of chronic rhinosinusitis makes the same point from the medical side: that condition is typically on both sides, and one-sided symptoms should prompt a faster referral (CMAJ).
If the tooth is the source, the fix is the tooth, usually a root canal or an extraction, and the sinus settles once the source is gone. Our post on root canals in Toronto explains what that treatment involves.
Do you need antibiotics for a sinus toothache?
Usually not, for either the sinus or the tooth.
Start with the sinus. Public Health Ontario says most sinus infections are caused by viruses, antibiotics don't work against viruses, and 9 of 10 people feel better within 1 to 2 weeks whether or not they take them (Public Health Ontario).
Choosing Wisely Canada's ear-nose-and-throat list estimates a bacterial infection in only 2% to 10% of acute sinus infections, and says antibiotics should generally be avoided unless symptoms have lasted at least 7 days (Choosing Wisely Canada).
Now the tooth. The Canadian Dental Association's Choosing Wisely list is blunt: "Don't prescribe antibiotics for toothache or localized dental abscess." Toothache pain comes from an inflamed nerve, not from an infection, so antibiotics don't relieve it; the treatment is removing the damaged pulp through a root canal or an extraction (Choosing Wisely Canada).
The CDA's own antibiotics page says most toothaches can be treated by removing the original source of pain and early infection without them (Canadian Dental Association).
One more honest note. A systematic review found no good evidence that fever or facial and dental pain can separate a bacterial sinus infection from a viral one, and concluded those symptoms shouldn't be used to decide on antibiotics (Otolaryngology-Head and Neck Surgery via PubMed).
So "my teeth hurt" is not a reason for a prescription on its own. It's a reason for an examination.
When should you see a dentist, and when should you see a doctor?
Match the pattern, and don't wait out the week if swelling or fever shows up.
See a dentist first if the pain is in one tooth, it reacts to cold, sweet or biting, there's no congestion, or the ache outlasts the cold. The Ontario Dental Association says that for constant or severe mouth pain you should "call your dentist immediately" and ask to be seen as soon as possible (Ontario Dental Association).
Swelling changes the urgency. The Canadian Dental Association says that if an infection has progressed to swelling of the face or under the eye, antibiotics are likely needed and you should visit your dentist as soon as possible (Canadian Dental Association). Our emergency dentist guide for Toronto covers what counts as same-day.
See your family doctor or a walk-in clinic first if several upper teeth ache together with a stuffy nose and facial pressure, and it all began with a cold. Public Health Ontario's advice on when to seek further help: symptoms such as facial pain, nasal congestion or discharge not improving or lasting longer than 7 days, new or worsening symptoms, or a new or persistent fever (Public Health Ontario).
Not sure which you have? Come to the dentist anyway. We have the tools to rule the teeth in or out: a cold test, a gentle tap on each tooth, a look at the gums and an x-ray.
A review written for dentists put it plainly: when a patient has pain in the upper back teeth, it's appropriate to rule out sinusitis before starting any definitive dental treatment (Dentistry Today via PubMed).
Some days the schedule pushes me, and I still won't drill a tooth that tests healthy. If every upper tooth on that side taps sore and the x-ray is clean, you leave with a note for your physician rather than a filling.
What can you do while you wait for your appointment?
The steps below hold you until you're seen. They don't replace the visit.
- For the sinus side, Public Health Ontario's list is saline nasal spray or rinse, water, rest, and fever or pain relief, with your pharmacist or physician guiding what's right for you (Public Health Ontario).
- Don't put a heating pad or hot water bottle on your jaw. The Ontario Dental Association says the heat will make things worse instead of better (Ontario Dental Association).
- Don't rest a painkiller against the sore tooth. The same ODA page says not to put the pills on your sore tooth (Ontario Dental Association).
- Keep a note of which teeth hurt and what sets it off. That history is half my diagnosis before I've looked in your mouth.
Frequently Asked Questions
Q: Can a sinus infection cause tooth pain on one side only? Yes. The CMAJ sinusitis guide lists one-sided facial pain among the findings that make sinusitis more likely (CMAJ), and a sinus infection that starts from a tooth most commonly shows up on one side (World Journal of Otorhinolaryngology via PubMed). One tooth on one side with no congestion still points to the tooth, so have it checked.
Q: How long does sinus tooth pain last? It follows the sinus. Public Health Ontario says 9 of 10 people with a sinus infection feel better within 1 to 2 weeks, with or without antibiotics (Public Health Ontario). If the toothache outlasts the cold, or narrows down to one tooth, book a dental visit.
Q: Can a sinus infection make your lower teeth hurt? Not directly. The sinuses that cause tooth pain sit above the upper teeth, and they're the most commonly affected sinuses (Government of Canada). There's no sinus under your lower teeth, so a lower toothache during a cold is more likely a tooth, a gum or jaw clenching, and deserves a dental look.
Q: Do antibiotics help a sinus toothache? Usually not. Most sinus infections are viral, and antibiotics don't work against viruses (Public Health Ontario). For the tooth itself, the Canadian Dental Association's Choosing Wisely list says "Don't prescribe antibiotics for toothache or localized dental abscess," because the pain comes from inflammation, not infection (Choosing Wisely Canada).
Q: Can a toothache turn into a sinus infection? Yes. The CMAJ guide attributes 5% to 10% of bacterial maxillary sinusitis to dental root infection (CMAJ), and a 2022 review found oral antibiotics are generally ineffective for that type until the tooth is treated (World Journal of Otorhinolaryngology via PubMed). A sinus infection that keeps returning on one side is a reason to have the upper teeth x-rayed.
Reviewed by Dr. Abinaash Kaur, B.Sc., DDS (University of Toronto Faculty of Dentistry), who has practised general and family dentistry in Bloor West Village for about 25 years. This article is general oral health information, not a diagnosis or a substitute for an examination.
Upper teeth aching and not sure whether it's a cold or a tooth? Come in and we'll test the teeth properly, with an examination and an x-ray rather than a guess. If it turns out to be your sinus, we'll tell you that too and point you to your physician. We're at 750 Annette Street in Bloor West Village, serving the Junction, High Park, and Baby Point. Book a visit with The Village Dentist and we'll take a proper look.
