Key Takeaways
- Sinus infections swell the air spaces behind the cheeks, forehead, and nose, trapping fluid and often mimicking a toothache.
- Warning signs include a lingering cold, thick mucus, facial pressure, a severe headache, and aching upper back teeth.
- Viruses cause most cases, and anything blocking sinus drainage, like allergies, smoke, or polyps, can trigger one.
- Infected upper tooth roots and deep gum pockets can spread into the sinus, and one study found a dental cause in 24% of confirmed cases.
- See a provider if symptoms last beyond 10 days, you have a prolonged fever, severe pain, a relapse, or repeat infections.
- Warm compresses, nasal rinses, antihistamines, and short-term decongestants ease symptoms, while antibiotics help only bacterial cases.
What Is a Sinus Infection?
Few things are more frustrating than pain you cannot explain. Pressure in your face, a blocked nose, and sore upper teeth can leave you wondering whether to call your doctor or your dentist.
The answer depends on the cause, and a sinus infection is one of the most common ones. A sinus infection, or sinusitis, happens when the air-filled spaces behind your cheeks, forehead, and nose swell and fill with fluid, giving germs a place to grow.
At Periodontal Specialists, our periodontal services include helping patients figure out whether the pain comes from the gums, a tooth, or the sinuses. Below, we cover the symptoms of a sinus infection so you can decide your next step.
Symptoms of a Sinus Infection
Most sinus infections start like an ordinary cold and then refuse to leave. Here are the signs of a sinus infection we hear about most:
- A stuffy or runny nose, often on one side more than the other
- Thick, cloudy, yellow, or green mucus
- Pressure or pain in your cheeks, forehead, or around your eyes
- Mucus dripping down the back of your throat, which can cause a sore throat or cough that gets worse at night
- A headache that feels heavier when you bend forward
- A reduced sense of smell or taste
- Bad breath, tiredness, and sometimes a fever
- A dull ache in several upper back teeth
How Long Do Sinus Infection Symptoms Last?
Doctors group sinus infection symptoms by how long they stick around:
- Acute sinusitis: 4 weeks or less
- Subacute sinusitis: About 1 to 3 months
- Chronic sinusitis: Longer than 3 months, usually with milder but more stubborn symptoms
What Causes a Sinus Infection?
Viruses cause most sinus infections, and bacteria cause some, per the CDC. Anything that blocks the small openings that drain your sinuses can trap mucus and start the problem.
The most common causes of sinus infections and risk factors are:
- A recent cold
- Seasonal allergies
- Smoking or regular exposure to secondhand smoke
- Nasal polyps or other structural issues inside the nose
- A weakened immune system, or medicines that weaken it
Can a Tooth Cause a Sinus Infection?
Yes, and it is quite common. When the roots of an upper molar sit right against the sinus floor, an infection at the root tip or deep gum pocket can spread upward into the sinus.
A 2017 study reviewed CT scans of patients with confirmed sinusitis and found a dental cause in 24% of cases. When only one side was infected, that number rose to 40%. The authors linked these cases to infected tooth roots and to bone loss from gum disease.
When Should You See a Doctor?
The CDC advises seeing a healthcare provider if you have:
- Symptoms lasting more than 10 days without getting better
- A fever that lasts longer than 3 to 4 days
- A severe headache or facial pain
- Symptoms that get better and then get worse again
- Several sinus infections within the past year
How Is a Sinus Infection Diagnosed?
Most of the time, a doctor diagnoses sinusitis from your history and a physical exam. They listen to how long your symptoms of a sinus infection have lasted and whether they have changed, then check your nose, face, and throat.
Your doctor may:
- Press or tap over your cheeks and forehead to check for tenderness
- Look inside your nose for swelling, pus, or polyps using a light source or otoscope
- Refer you to an ear, nose, and throat (ENT) specialist for nasal endoscopy, which uses a thin camera to view the sinus openings
- Order a CT scan if symptoms are chronic, keep returning, or a structural problem is suspected
What a Dental Exam Adds
When sinus symptoms stay on one side or keep coming back, a dental exam can fill in the missing piece. At our offices, Dr. Thomas Wolfe checks your upper back teeth for decay, cracks, or old root canals that may be failing. We also measure gum pockets and look at dental X-rays for bone loss between the roots and the sinus floor. If a tooth or gum problem shows up, you can bring those findings to your physician or ENT so both sides of the problem get treated.
How Do You Treat a Sinus Infection
While many sinus infections can resolve without medical intervention, the following treatments may offer relief:
- Try using a warm compress to alleviate discomfort and pressure by loosening up the liquid in the sinuses.
- Use a nasal wash or sinus rinse. You can purchase it online from drug stores.
- Take antihistamine tablets to lower inflammation in the sinuses. These are available in drugstores, supermarkets, and online platforms.
- Use a nasal decongestant spray to help clear the sinuses and relieve pressure. You can also buy these sprays from supermarkets, drugstores, and online.
Remember: It’s important to avoid using decongestants for an extended period without consulting a doctor, as they can exacerbate congestion if used for too long.
Antibiotics get requested a lot, but they only work against bacteria. A provider may suggest watching and waiting for 2 to 3 days before deciding. Our team takes the same careful approach and prescribes only when a patient truly needs it.
Final Thoughts
A useful habit is to keep a short note on your phone: when the congestion started, which side it is on, and whether any upper teeth ache when you bite or bend over. That note helps your doctor decide on antibiotics, and it tells us whether a tooth needs a closer look.
If the symptoms of a sinus infection keep returning on one side, or an upper tooth aches every time your sinuses flare, a dental check is a sensible next step. The team at Periodontal Specialists has over 50 years of experience examining upper molars and the gums around them, so patients get a clear answer about whether the problem is dental.
Patients across southern Minnesota visit our periodontal specialists in Northfield, MN, at 1605 Heritage Dr, and we also see patients in Red Wing, Owatonna, Rochester, and Winona.
Northfield office: 1605 Heritage Dr, Northfield, MN 55057
Phone: 507-663-1815
Email: northfield@periodontalspecialists.com
Hours: Mon-Thur 8am–5pm, Fri 8am-12pm
FAQs
The sinus infection itself does not spread from person to person. The cold virus that often comes before it can, so hand washing and covering coughs still help protect the people around you.
Mucus draining down the back of your throat gives odor-causing bacteria something to feed on. A strong, foul smell on one side can point to a dental source, since mouth bacteria produce that odor, and it is worth having your upper teeth checked.
Many patients with a history of sinusitis can still have a sinus lift. An active sinus infection needs to clear first, and your periodontist will review your sinus health on imaging before planning surgery.
It can, though it is uncommon. A failing root canal in an upper molar can let infection reach the sinus, and removing an upper tooth whose roots touch the sinus can occasionally leave a small opening. Your dentist checks for this and treats it if it happens.
