You’re chewing dinner. Out of nowhere—bam. A sharp throb shoots through your bottom teeth.
What gives?
Why do my bottom teeth hurt all of a sudden?
You didn’t bang your jaw. You didn’t chew rocks. But that pain? It’s real. And it came out of nowhere. This guide breaks down real reasons why your bottom teeth might hurt, what could be behind sudden pain, and what to do next.
1. Tooth Grinding or Clenching (Bruxism)
Let’s not sugarcoat it. Most folks grind their teeth and don’t even know it.
You might:
- Clench during sleep
- Clench when stressed
- Grind when anxious
This puts insane pressure on your bottom teeth.
What happens?
- Enamel wears down
- Dentin underneath gets exposed
- You feel pain and sensitivity
Your bottom teeth might hurt when you wake up or during the day. This is one of the most overlooked causes of sudden tooth pain.
Fix it:
- Wear a mouthguard (talk to your dentist)
- Practice stress relief
- Track symptoms
2. Cavity in a Bottom Tooth
Don’t think cavities only happen to kids.
Adults get them too—especially on the chewing surface of bottom molars. If a cavity gets deep enough, it hits the nerve.
Symptoms:
- Sudden sharp pain
- Hot or cold sensitivity
- Pain when chewing
Why this hurts: The decay eats through the enamel and dentin, reaching the tooth root. That’s when the pain hits hard.
Fix it:
- Fillings or root canal (your dentist will decide)
3. Gum Disease Is Wrecking Your Mouth
Bleeding gums? Bad breath? Loose teeth? You might have gum disease.
It usually starts as gingivitis—red, puffy gums. If ignored, it becomes periodontitis. That messes with the bone holding your teeth.
Why do your bottom teeth hurt?
- The gum pulls away from the teeth
- Bacteria get in deep
- Your bottom teeth throb or ache
You might also notice:
- Swollen gums
- Pus near teeth
- Pain when brushing
Fix it:
- Deep cleaning (scaling and root planing)
- Better brushing + flossing
Check ADA’s guide to gum disease
4. Tooth Abscess = Big Trouble
This one’s nasty.
A dental abscess is a pocket of pus caused by infection. It usually comes from a deep cavity or cracked tooth that got ignored.
Warning signs:
- Throbbing or shooting pain
- Swollen jaw or gums
- Bad taste in mouth
An abscess can make multiple teeth hurt—especially bottom teeth if the infection is near the lower jaw.
Fix it fast:
- See a dentist ASAP
- You might need a root canal or extraction
More info on dental abscess from Mayo Clinic
5. Cracked or Broken Teeth
You don’t need a full-on chipped tooth to feel pain.
Tiny hairline fractures can cause sharp pain when you bite or drink something cold.
Your bottom teeth are vulnerable if:
- You bite hard foods
- You grind your teeth
- You’ve had past dental work
Pain may:
- Come and go
- Feel sharp and sudden
- Get worse over time
Fix it:
- Your dentist might bond the tooth or recommend a crown
6. Sinus Infection (Yes, Really)
This one surprises people.
A sinus infection can cause pain in your upper and lower teeth. That’s because your sinus nerves are close to the roots of your teeth.
Even though it’s more common with top teeth, pain can radiate to the bottom too.
Signs of sinus pain:
- Stuffy nose
- Facial pressure
- Pain in multiple teeth
If multiple teeth suddenly ache and you’ve got cold symptoms, sinus might be the reason.
7. Tooth Sensitivity (Hot, Cold, Ouch)
Ever bite into ice cream and jump?
That might be tooth sensitivity—caused by:
- Worn enamel
- Gum recession
- Brushing too hard
- Whitening treatments
Bottom teeth hurt when:
- You eat hot or cold foods
- You use certain toothpaste
- You breathe in cold air
Fix it:
- Use toothpaste for sensitive teeth
- Switch to a soft brush
- Stop overbrushing
More from Healthline on sensitive teeth
8. You’re Brushing All Wrong
Hard brushing doesn’t mean better brushing.
If you scrub too hard, you wear down the tooth enamel and cause gum recession. Both lead to exposed dentin = pain.
Look for:
- Notches near the gumline
- Sudden sharp pain when brushing
- Gums pulling away
Do this instead:
- Use a soft brush
- Gentle circular motion
- Don’t rush
When to See a Dentist
If pain sticks around for more than 48 hours—book an appointment.
If you notice swelling, fever, or pus—get in ASAP.
Your dentist will look for:
- Fractures
- Infection
- Cavities
- Gum disease
They’ll recommend appropriate treatment based on the cause of the pain.
FAQs: Why Do My Bottom Teeth Hurt All of a Sudden?
Q: Can stress make your bottom teeth hurt? Yes. People clench their jaw when anxious, leading to tooth pain.
Q: Do I have to visit a dentist right away? If it lasts more than a day or gets worse—yes.
Q: Can sensitive teeth cause pain in just the bottom teeth? Absolutely. Especially if enamel is worn or gums have receded.
Q: What if my bottom teeth hurt only when I chew? Could be a cracked tooth or cavity.
Q: Why do multiple bottom teeth hurt all at once? Think gum disease, sinus issues, or clenching.
Bottom line?
If your bottom teeth hurt all of a sudden, don’t ignore it.
It could be a cavity, grinding problem, gum disease, or even a sinus issue.
Get it checked. Don’t wait for it to get worse—your smile deserves expert care. At West Hollywood Smile Dental, we offer gentle, high-quality solutions for everything from cavities to grinding-related pain. Book your appointment today and let our experienced team bring back your comfort—and your confident smile.
