Tooth abscess: signs, stages and treatment

What are the signs of a tooth abscess?

The most common sign is a throbbing pain, which can spread to the ear, jaw or neck.  The tooth may hurt when you bite, or feel slightly raised.  Your gum or face may swell.  You may notice a small spot on the gum that leaks fluid, sometimes called a gum boil.  A bad taste or smell in the mouth is also common.  Some people feel generally unwell, or have a raised temperature.

Some abscesses cause little or no pain, especially once the infection has found a way to drain.  The infection is still there, and is often picked up on an X-ray.

How does a tooth abscess develop?

• Stage 1: decay, a crack or a leaking filling lets bacteria into the pulp, causing inflammation known as pulpitis.
• Stage 2: without treatment, the inflamed pulp loses its blood supply and dies.
• Stage 3: bacteria spread from the root canals into the bone at the tip of the root.
• Stage 4: an abscess forms, causing pain and swelling.  If the infection finds a way out through the gum, the pain may ease, but the infection remains.

Read more in my guide to pulpitis.

Will a tooth abscess go away on its own?

No.  An abscess may settle for a while, but the infection does not go away, and the tooth can become painful again.  The source of the infection is inside the tooth, so the abscess will keep coming back until the bacteria inside the tooth are removed.

Do antibiotics cure a tooth abscess?

Antibiotics do not cure a tooth abscess on their own.  Antibiotics can help when an infection is spreading or you feel unwell, but they cannot reach the bacteria inside a tooth whose pulp has died.  The infection inside the tooth needs to be treated.

How is a tooth abscess treated?

Root canal treatment removes the infected pulp, then cleans, disinfects and seals the canals.  This lets the bone around the root heal while keeping the tooth.  When an abscess develops on a tooth that has already had root canal treatment, root canal re-treatment is used.  Extraction may be needed when a tooth cannot be restored.  A CBCT scan and examination under the microscope help to show the extent of the infection before treatment is planned.  Read more about root canal re-treatment.

When is a tooth abscess an emergency?

Seek urgent medical help, or go to A&E, if you have swelling that spreads to the eye or neck, difficulty swallowing or breathing, or a high temperature with the swelling.

Frequently asked questions

Should I pop or drain a tooth abscess at home?
No.  Squeezing an abscess can push the infection deeper, and squeezing will not remove the source of the infection, which is inside the tooth.

Can a tooth with a crown or a root filling get an abscess?
Yes.  Bacteria can enter around a crown or filling that has started to leak, or remain in parts of the canal system that were not fully cleaned.

How much does treatment cost?
Read more about what affects the cost of root canal treatment.