Sinus Infection or Toothache? How to Tell the Difference

Upper Tooth Pain Doesn't Always Mean Tooth Problems

You have pain in your upper back teeth, and you're not sure if it's a sinus infection or a cavity. This confusion is incredibly common because your maxillary sinuses (behind your cheekbones) are very close to your upper tooth roots. Pain from one often feels like pain from the other.

Why Sinus Infections Cause Tooth Pain

Your maxillary sinuses sit directly above your upper back teeth. When a sinus infection develops:

• Inflammation and fluid buildup create pressure above your tooth roots
• Your brain interprets this pressure as tooth pain
• The pain feels like it's coming from multiple teeth (not just one)
• Pain worsens when you bend forward (gravity pulls fluid downward, increasing pressure)

This is referred pain—just like dental problems can feel like ear pain.

Sinus Infection vs. Toothache: How to Tell

The "Tap Test": Useful Diagnostic Clue

Tap gently on the problematic tooth with your finger or the back of a spoon:

• If it hurts sharply → Likely a tooth problem (inflammation at the root)
• If it doesn't hurt → Likely sinus-referred pain (the tooth itself is healthy)

This isn't a definitive test, but it's a helpful clue.

Secondary Sinus-Dental Connection: Odontogenic Sinusitis

Here's where it gets complicated: Sometimes a dental infection actually causes a sinus infection.

How it happens:

• You have an untreated tooth abscess
• Infection from the tooth spreads to the maxillary sinus above it
• Now you have both a dental infection and a sinus infection
• You need treatment for both problems

Signs of this scenario:

• Severe tooth pain with sinus congestion/pressure
• Both tooth and sinus symptoms start around the same time
• Multiple teeth affected with one tooth being significantly more painful than others
• Pus drainage from both tooth and nasal passages
• Fever (more common with this than pure sinus infection)

When to See a Dentist vs. Doctor

See a dentist if:

• Pain is localized to one tooth
• Pain worsens with chewing or biting
• Tooth is sensitive to hot/cold
• You can see decay or a filling problem
• Tap test causes pain
• You have no nasal symptoms

See a doctor (or your primary care) if:

• Pain affects multiple teeth
• Pain is more pressure/throbbing than sharp
• You have nasal congestion, drainage, or cough
• Pain worsens when you bend forward
• You have facial pressure between eyes or above cheekbones
• You have fever
• Symptoms started with cold symptoms

See both if:

• You have unclear symptoms
• You have both dental and sinus symptoms
• First visit didn't identify the problem
• Symptoms don't improve after treatment

Diagnostic Approach

Your dentist will:

1. Ask detailed questions about your symptoms and onset
2. Perform tap test on problematic teeth
3. Check for decay visually and with X-rays
4. Assess bite (tooth-pain is worse with certain bites)
5. Check response to temperature (healthy teeth respond to hot/cold)
6. Take X-rays (can show decay, abscess, or bone loss)

Your doctor will:

1. Ask about nasal symptoms (congestion, discharge, cough)
2. Examine your sinuses (palpate, look for sinus tenderness)
3. Check vital signs (fever, general illness appearance)
4. Possibly order imaging (X-ray or CT of sinuses)

Treatment: Different for Each Condition

Sinus infection treatment:

• Decongestants (pseudoephedrine, oxymetazoline spray)
• Antihistamines (if allergies contribute)
• Saline rinse (gentle sinus irrigation)
• Antibiotics if bacterial (amoxicillin, azithromycin, others)
• Corticosteroid spray (reduces inflammation)
• Pain relief (ibuprofen, acetaminophen)

Tooth infection treatment:

• Root canal (if nerve is infected)
• Extraction (if tooth is too damaged)
• Antibiotics (to manage infection temporarily)
• Pain relief (local anesthesia, ibuprofen)
• Possibly filling or crown (after root canal)

Key difference: Antibiotics alone won't fix a tooth infection—you need dental treatment. Similarly, dental treatment alone won't fix a sinus infection.

Why This Matters for Treatment

If you have a sinus infection and are treated for a tooth problem:

• The tooth treatment won't help the sinus pain
• The sinus infection will linger or get worse
• You'll be frustrated and in pain
• You'll feel like the dental treatment didn't work

If you have a tooth infection and are treated for sinusitis:

• Antibiotics might help temporarily (managing the infection systemically)
• But the infected tooth is still there
• Pain will return
• Infection can spread

How to Investigate Before Your Appointment

Questions to ask yourself:

1. Does the pain feel localized to one tooth or diffuse across multiple teeth?
2. When did it start—suddenly or gradually?
3. Did it start after you caught a cold or got congested?
4. Do you have nasal congestion or drainage?
5. Does pain worsen when you bend down?
6. Does pain worse when you chew?
7. Have you seen a dentist recently? Are your teeth healthy?

Your answers guide whether you need a dentist or doctor (or both).

The Practical Path Forward

If uncertain, here's the best approach:

1. See your dentist first (they can rule out tooth problems in 15 minutes)
2. If dentist finds nothing, then see your doctor
3. If dentist finds a problem, get it treated
4. If doctor finds a problem, get it treated
5. If both found nothing, revisit each provider (might need specialist referral)

Most cases resolve once you identify and treat the actual problem.

Reassurance: Tooth pain and sinus pain are almost never actually confusing once you see a professional. A dentist can tell within minutes if your upper molars are healthy. A doctor can tell if you have sinus infection. You'll get clarity quickly once you seek appropriate care.

That upper tooth pain might be sinuses, might be teeth, or might be both. One dentist appointment will probably answer the question. Get checked out.