Dental Fillings: Types, Procedure and How Long They Last

6 days ago

4 min read

Updated: 2 days ago

Written and medically reviewed by Dr. Baraa Alnahhal, MD · Last reviewed: November 2026 · How we review

Quick Answer

Dental fillings repair cavities and minor chips or cracks by filling in the damaged part of a tooth, usually in one visit. Common materials are tooth-colored composite resin, silver-colored amalgam and glass ionomer. Depending on the material, they last 10 to 20 years. Call your dentist if you have severe or lasting pain, swelling or fever.

What the research says

Amalgam fillings last longer than composite: a Cochrane review found tooth-colored composite fillings in back teeth had almost twice the failure rate of amalgam fillings, with no clear safety differences between them (Worthington HV et al., Cochrane Database of Systematic Reviews, 2021) [2]
Amalgam didn't harm children's thinking or kidneys: in a 5-year trial of 534 children aged 6 to 10, amalgam fillings caused no significant differences in IQ, memory or kidney function compared with composite fillings (Bellinger DC et al., JAMA, 2006) [3]

Key takeaways

Fillings repair cavities and minor tooth damage.
The tooth is numbed, decay is removed and the space is filled.
Common materials are composite, amalgam and glass ionomer.
Fillings usually last 10 to 20 years.
Mild sensitivity for a week or two is normal.

What are dental fillings?

When tooth decay creates a hole (cavity), a filling seals it to stop the damage from spreading. Fillings are a type of dental restoration, a group that also includes inlays, onlays, crowns and bridges. Depending on the type, fillings can strengthen weak teeth, preserve healthy tooth structure, restore chewing and improve appearance. Sources: [1]

Types of fillings

Types of dental fillings: direct fillings placed in one visit (amalgam, composite resin, glass ionomer) and indirect fillings made in a lab (porcelain or gold inlays and onlays)

Your dentist helps choose the right material.

Type	Material	Notes
Amalgam (direct)	Mercury mixed with silver, tin, zinc and copper	Silver-colored; very durable
Composite resin (direct)	Resin with quartz, silica or glass	Tooth-colored; hardened with a special light
Glass ionomer (direct)	Glass powder	Tooth-colored
Inlays and onlays (indirect)	Porcelain or gold	Made in a lab; used when damage is too large for a filling but not enough for a crown; usually two visits

Sources: [1]

How a filling is placed

Dental filling steps: numb the tooth, remove decay, fill the space, harden with a curing light for composite, polish and check your bite

Most fillings take one visit.

Your dentist numbs the tooth with a local anesthetic.
Decayed or damaged tooth tissue is removed.
The space is filled with the chosen material.
Composite fillings are hardened with a curing light.
The filling is polished and smoothed.
Your dentist checks your bite and adjusts as needed. Sources: [1]

Sedation options are available if you feel anxious at the dentist. Sources: [1]

After a filling

Most people go back to normal activities right away.
Wait for the numbness to wear off before eating so you don't bite your cheek.
Mild sensitivity and gum soreness are normal and usually fade in a week or two.
Over-the-counter pain relievers such as acetaminophen or ibuprofen can help. Sources: [1]

Possible problems

Problem	What it may mean
Throbbing toothache	Decay may have reached the pulp; you may need a root canal
Pain when biting	The filling may need reshaping
Lasting pain with heat or cold	Possible nerve damage; may need a root canal or extraction

Sources: [1]

Is amalgam safe?

Amalgam safety: considered safe by the ADA and FDA; the FDA suggests some groups avoid it when possible, including pregnant or breastfeeding people, young children, people with certain nerve or kidney conditions and those allergic to mercury; intact fillings shouldn't be removed

Removing healthy amalgam fillings can increase mercury exposure.

The American Dental Association, the FDA and public health agencies consider amalgam safe. The FDA suggests some people avoid it when possible: people who are pregnant, planning pregnancy or breastfeeding; children, especially under 6; people with nerve conditions such as Alzheimer's, multiple sclerosis or Parkinson's; people with kidney problems; and people allergic to mercury. The FDA doesn't recommend removing intact amalgam fillings, since that can increase mercury exposure. Sources: [1, 3]

How long fillings last

Depending on the material, fillings can last 10 to 20 years. Good brushing, flossing and regular checkups help them last longer. Sources: [1, 2]

When to call your dentist

Your filling breaks.
You have severe pain that medicine doesn't relieve.
Your face or jaw swells.
You have a fever, chills or other signs of infection. Sources: [1]

Conclusion

Dental fillings are a quick, routine way to stop decay and protect your teeth. Your dentist will help you choose the material that best fits your tooth, budget and health.

Keep learning: read about cavities and tooth decay and root canal treatment.

Frequently asked questions

What is a dental filling?

A material that fills a cavity or repairs minor tooth damage.

Does getting a filling hurt?

No. The tooth is numbed first.

What are fillings made of?

Composite resin, amalgam, glass ionomer, porcelain or gold.

Which filling lasts longest?

Amalgam tends to last longer than composite in back teeth.

How long do fillings last?

Usually 10 to 20 years, depending on the material.

Is sensitivity after a filling normal?

Yes, for about a week or two.

When can I eat after a filling?

Once the numbness wears off.

Are silver fillings safe?

The ADA and FDA consider them safe, though some groups should avoid them when possible.

Should I replace my old amalgam fillings?

Not if they're intact; removal can increase mercury exposure.

What if my tooth still hurts?

Call your dentist; you may need a bite adjustment or a root canal.

References

Cleveland Clinic. Dental Fillings: Types, Materials & What They're For. Cleveland Clinic. Last updated May 13, 2024. https://my.clevelandclinic.org/health/treatments/17002-dental-fillings
Worthington HV, Khangura S, Seal K, et al. Direct composite resin fillings versus amalgam fillings for permanent posterior teeth. Cochrane Database of Systematic Reviews. 2021;8(8):CD005620. PMID 34387873. https://doi.org/10.1002/14651858.CD005620.pub3
Bellinger DC, Trachtenberg F, Barregard L, et al. Neuropsychological and renal effects of dental amalgam in children: a randomized clinical trial. JAMA. 2006;295(15):1775-1783. PMID 16622139. https://doi.org/10.1001/jama.295.15.1775

Medical disclaimer

This article is for general education only and does not replace advice from a qualified healthcare professional. Talk to your doctor about your own diagnosis and treatment, and seek emergency care right away for severe or sudden symptoms.