Dental Abscess

A pus-filled sac that develops in or around the root of a tooth

  • Poor oral hygiene and a diet high in sugar are risk factors
  • Age, gender, and genetics are not significant factors

An accumulation of pus in or around the root of a tooth is known as a dental abscess. An abscess usually develops as a complication of dental caries, which gradually destroys the layer of enamel on the outside of the tooth and the inner dentine, allowing bacteria to invade the soft central core, or pulp, of the tooth (see Pulpitis). Eventually, a dental abscess may form. The pulp may also become infected if a tooth is damaged by a blow to the mouth (see Fractured tooth).

An abscess may also form as a result of certain types of gum disease (see Periodontitis). Periodontitis is usually caused by a build-up of dental plaque (a deposit including food particles, saliva, and bacteria) in a pocket that forms between a tooth and gum.

A dental abscess can be extremely painful and may cause the tooth that is affected to loosen in its socket.

Dental abscess

Tooth decay and infection has spread through the tooth, and pus has gathered at the root of the tooth. If it is not treated, the tooth will have to be extracted.

What are the symptoms?

The main symptoms of a dental abscess develop gradually and may include:

  • Severe pain on touching the affected tooth and on biting or chewing.

  • Loosening of the affected tooth.

  • Red, tender swelling of the gum over the root of the tooth.

  • Release of pus into the mouth.

If untreated, the infection may make a channel from the tooth to the surface of the gum, and a painful swelling, known as a gumboil, may form. If the gumboil bursts, foul-tasting pus is released and the pain decreases. In some cases, the channel may persist, leading to a chronic (long-standing) abscess that discharges pus periodically.

If the infection spreads, the face may become swollen and painful, and a fever may also develop. If you suspect that you have a dental abscess, you should consult your dentist as soon as possible.

What can I do?

Taking painkillers, such as paracetamol, may help until you can see your dentist. Rinsing your mouth with warm salt water may also help to relieve the pain and encourage a gumboil to burst. If a gumboil does burst, you should wash away the pus thoroughly with more warm salt water.

What might the dentist do?

Your dentist will ask you about your symptoms and examine your teeth and gums. He or she may take an X-ray of your mouth to confirm the diagnosis (see Dental checkup).

If the abscess has been caused by decay, your dentist may try to save the tooth. Under a local anaesthetic, a hole is drilled through the top of the tooth to release the pus and relieve the pain. If there is a gumboil, a small cut may be made to drain the pus and the cavity is then cleaned with an antiseptic solution. You will probably also be given a course of antibiotics. Once the infection has cleared up, you will probably need root canal treatment. If it is not possible to save the tooth, it will be extracted.

To treat an abscess caused by gum disease, your dentist may use a scaler to scrape out the plaque from the pocket between the affected tooth and gum. The pocket is then washed out with an antiseptic solution. In a severe case, the affected tooth may need to be extracted.

What is the prognosis?

Treatment is usually successful, but a small area of infection may persist and further treatment may be required.

From the 2010 revision of the Complete Home Medical Guide © Dorling Kindersley Limited.

The subjects, conditions and treatments covered in this encyclopaedia are for information only and may not be covered by your insurance product should you make a claim.

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