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Dental Abscess

(Tooth Abscess)

Reviewed/Revised Mar 2024 | Modified Jul 2025
v34376867

Topic Resources

What is a dental abscess?

An abscess is a collection of pus. Pus is a mix of white blood cells, dead tissue, and bacteria. It builds up wherever your body is fighting an infection.

A dental abscess is an abscess that forms around the root of your tooth. A severe abscess can spread into your gums, cheeks, or jawbone.

What causes a dental abscess?

A dental abscess is caused by bacteria that get in the pulp of your tooth or in the gums surrounding the tooth. The pulp can become infected when you have a deep cavity or a cracked tooth.

Your body attacks the infection with large numbers of white blood cells. The dead white blood cells become the pus that forms the abscess.

A Look Inside a Tooth

What are the symptoms of a dental abscess?

A dental abscess causes:

  • Constant tooth pain that gets worse when you chew food

  • Sensitivity to hot or cold food

  • Swelling of your gums

  • Sometimes, fever

  • Sometimes, swelling of your jaw, the floor of your mouth, or cheeks

  • Sometimes, difficulty opening your mouth or swallowing

Eventually the abscess can break open, letting the pus drain.

How do dentists treat a dental abscess?

Dentists give you pain medicine and antibiotics and treat the abscess by:

  • Draining the pus with surgery or a root canal

Root canal is a dental procedure to remove the pulp from your tooth. The dentist then fills and seals the tooth canal.

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