Why Do Cavity Fillings Hurt? Your Complete Guide
Do your teeth hurt after getting a cavity filling? You are not alone! Many people feel pain after the dentist fixes their tooth. This guide will help you understand why fillings hurt and what you can do about it.
Table of Contents
Quick Facts About Cavity Filling Pain
- 50% of children aged 6-9 have cavities that need fillings
- 30-40% of people feel some pain after getting a filling
- Most pain goes away in 1-2 weeks
- 5-10% of fillings need to be fixed because they don’t fit right
Why Do Fillings Hurt? 6 Big Reasons
1. Nerve Irritation
When the dentist drills deep in your tooth, it can bother the nerve inside. This causes sensitivity and pain. Deep cavities that are close to the nerve hurt more.
2. Bite Problems
If your filling is too high, it will hit your other teeth when you bite down. This is called a “high filling” and it makes your tooth hurt when you chew.
A bite misalignment happens in about 5-10% of fillings. Your dentist can fix this by making the filling shorter.
3. Material Problems
Some people have a bad reaction to the filling material. This can make your tooth or gums hurt. There are different types:
- Amalgam fillings (silver)
- Composite resin fillings (white)
- Glass ionomer cement (clear)
The good news is that composite fillings cause less pain from hot and cold than amalgam fillings.
4. Gum Inflammation
Sometimes the tools used during the filling can hurt your gums. This causes swelling and pain around your tooth.
5. Cracked Filling
If your filling gets a crack, it can let bacteria in. This causes pain and might lead to more decay.
6. New Decay
Sometimes new decay can form under an old filling. This is called “recurrent decay” and it causes toothache.
Types of Pain and What They Mean
| Type of Pain | What It Might Mean | What to Do |
|---|---|---|
| Sharp zaps | Nerve irritation | Call dentist if it lasts more than 2 days |
| Throbbing pain | Possible infection | Call dentist right away |
| Pain when biting | High filling or cracked tooth | Dentist can adjust the filling |
| Cold/hot sensitivity | Exposed dentin or poor seal | Try sensitive toothpaste |
| Constant ache | Inflammation or infection | Take OTC pain medicine and call dentist |
How Long Should Filling Pain Last?
Most tooth sensitivity after a filling is normal and goes away on its own.
- 24-48 hours: Normal mild pain and sensitivity
- 1-2 weeks: Pain should get better each day
- More than 2 weeks: Call your dentist – this is not normal
About 15% of patients get tooth flexing pain after deep fillings. This pain can last longer.
5 Ways to Help Filling Pain at Home
1. Take Over-the-Counter Pain Medicine
Ibuprofen (Advil) or acetaminophen (Tylenol) can help with tooth pain. Follow the directions on the bottle.
2. Use Special Toothpaste
Toothpaste for sensitive teeth like Sensodyne or Colgate Sensitive Pro-Relief can help. These have special things that block pain signals from your tooth.
3. Saltwater Rinse
Mix warm water with salt and rinse your mouth. This helps with swollen gums and kills germs.
4. Avoid Things That Cause Pain
Stay away from:
- Very hot or cold foods
- Sweet foods
- Hard foods that need lots of chewing
- Acidic foods like oranges and soda
5. Try Clove Oil
Clove oil has a natural pain killer called eugenol. Put a tiny bit on a cotton ball and hold it on the sore tooth. But don’t use too much – it can burn.
When to Call Your Dentist
Call your dentist right away if you have:
- Pain that gets worse after 48 hours
- Swelling in your face or gums
- Fever with tooth pain
- A filling that feels loose or falls out
- Pain that keeps you from sleeping
Your dentist might need to:
- Adjust your bite
- Replace the filling
- Do a root canal if the pulp is damaged
Special Filling Situations
Pain During Pregnancy
Pregnant women can safely get fillings, but might feel more sensitivity due to hormonal changes. Talk to your dentist about safe pain relief options.
Children’s Filling Pain
Kids might not be able to explain their pain well. Pediatric dentistry experts use special techniques to make fillings less painful for children.
Seniors and Filling Pain
Older adults might have more receding gums which can make teeth more sensitive after fillings. Dental implants might be a better option for some seniors with multiple cavities.
Different Filling Materials and Pain
| Filling Type | Pain Level | Durability | Good For |
|---|---|---|---|
| Amalgam (silver) | More thermal sensitivity | Lasts ~14 years | Back teeth |
| Composite resin (white) | Less sensitivity | 7-10 years | Front teeth or visible areas |
| Glass ionomer | Reduced post-op sensitivity by 20% | 5-7 years | Small fillings near gum line |
| Ceramic/porcelain | Moderate | 10-15 years | Larger restorations |
| Gold | Minimal | 20+ years | Long-term durability |
Preventing Future Filling Pain
1. Catch Cavities Early
Small cavities need smaller fillings, which hurt less. Get regular dental checkups.
2. Good Home Care
Brush and floss every day to prevent new cavities.
3. Use Fluoride
Fluoride reduces cavity risk by 25-40% in adults. Use fluoride toothpaste and mouthwash.
4. Address Teeth Grinding
If you grind your teeth at night, get a custom night guard. About 12% of filling pain cases are linked to undiagnosed bruxism.
5. Choose the Right Filling Material
Talk to your dentist about which type of filling is best for you. Composite fillings cause less thermal sensitivity than amalgam fillings.
Common Questions About Filling Pain
Why does my tooth hurt months after a filling?
Pain that starts long after a filling might be from:
Cracked filling
Recurrent decay
Cracked tooth syndrome
Teeth grinding at night (bruxism)
An infection called a dental abscess
Are white fillings less painful than silver?
Composite resin fillings (white) typically cause less thermal sensitivity than amalgam fillings (silver). A study in the Journal of the American Dental Association found that patients report less sensitivity with composite fillings.
What helps with tooth sensitivity after a filling?
Desensitizing toothpaste with potassium nitrate
Fluoride treatments from your dentist
OTC pain relievers like ibuprofen
Soft foods diet for a few days
Bite adjustment if the filling is too high
Can a filling damage the nerve?
Yes, if the cavity was very deep, the drilling and filling process can irritate the tooth nerve (dental pulp). If the pain is severe or lasts more than two weeks, you might need a root canal therapy.
How long does numbness last after a filling?
Lidocaine or Novocain numbness typically lasts 1-3 hours. If you have lingering numbness after 4 hours, call your dentist.
Take Care of Your New Filling
A little sensitivity is normal after getting a filling, but too much pain is not. If you follow the tips in this article, you can feel better faster.
Remember:
- Most pain goes away in 1-2 weeks
- Use sensitivity toothpaste to help
- Call your dentist if pain gets worse instead of better
Take good care of your teeth to prevent needing more fillings in the future!
