A tooth abscess is a collection of pus that forms inside a tooth or its surrounding structures. The abscess itself is one of the later stages of tooth decay, and typically occurs before tooth loss.

Tooth abscesses develop in response to acquiring a bacterial infection inside the tooth, gums, or jaw bone. Such infections can occur due to tooth decay, gum disease, or a mouth injury.

Without treatment, a tooth abscess may worsen or spread to other areas of the body. However, the factors that lead to them develop in stages, and knowing these stages can help a person prevent or treat an abscess.

This article outlines what a tooth abscess is, including its symptoms and causes. We also outline the stages of tooth decay and provide tips on prevention and treatment.

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A tooth abscess is a collection of pus that develops inside a tooth or its surrounding structures. They occur due to a person contracting a bacterial infection in one of the following parts of the mouth:

  • the tooth pulp, the innermost part of the tooth
  • the gums
  • the jaw bone

The most common cause of tooth abscesses is tooth decay from untreated cavities. However, they can also develop as a result of gum disease or having an open wound within the mouth.

The abscess itself is one of the later stages of tooth decay. The different stages include:

  1. Enamel decay: Involves damage to the outermost layer of the tooth. Some people do not experience any symptoms, while others may notice increased sensitivity to heat and cold. Enamel decay can cause white spots on the teeth.
  2. Dentin decay: Involves decay to the layer beneath the enamel of the tooth. Some people may notice pain or sensitivity. In some cases, there may be a visible hole or cavity in the tooth.
  3. Pulp decay: This occurs when bacteria get deep into the innermost layer of the tooth. Bacteria inside the tooth pulp can attack the nerve of the tooth, causing intense pain. Sometimes, damage to the nerve means that a person first feels severe pain, then nothing at all.
  4. Abscess formation: An abscess occurs in the later stages of tooth decay, after the bacteria travels to the tooth pulp, or deeper into the gums or jawbone. A person may notice pain near the tooth, along with swelling and redness of the gums. A severe abscess may also trigger a fever.
  5. Tooth loss: A tooth that is severely decayed may break or fall out.

Some symptoms of an abscess include:

Without treatment, the bacteria from a tooth abscess can spread to the bloodstream. This may result in acquiring a serious and potentially life threatening infection called sepsis.

Some possible symptoms of sepsis include:

Tooth abscesses develop when bacteria in the mouth get deep inside a tooth or its surrounding structures, and then multiply out of control.

Below are some of the main causes of a tooth abscess.

Untreated cavities

Bacteria inside the mouth clump together to form a resilient biofilm called plaque. Regular brushing, flossing, and dental care can help remove plaque. However, without proper dental care, it can grow out of control.

Over time, plaque bacteria eat away at the tooth, causing tooth decay. If the decay continues without treatment, an abscess may develop.

Gum disease

Gum disease, also known as periodontitis, is the medical term for infection and inflammation of the gums.

Severe gum disease causes the gums to pull away from the teeth, exposing deep pockets between the teeth and gums. Food and bacteria can also become trapped inside the pockets, resulting in an abscess.

Recent injury to the mouth

An injury to the tooth or its surrounding structures can also increase the likelihood of a tooth abscess. These injuries could occur as a result of surgery or trauma to the mouth.

An untreated abscess can cause serious complications, such as:

When treating a tooth abscess, a dentist will prescribe antibiotics to kill the bacteria and stop them from spreading.

To prevent the infection from returning, the dentist will also need to treat the tooth decay or injury that caused the abscess. Treatment may include:

  • filling cavities
  • treating gum disease using a procedure called scaling and root planing, which cleans below the gumline
  • treating broken or lost teeth with crowns or implants

In rare cases, the bacteria from an abscess can spread to the bloodstream and other organs within the body. A person with a widespread bacterial infection will require intravenous antibiotics at the hospital. They may also require surgery to remove tissues that have become severely damaged by the infection.

A person can take the following steps to help prevent dental abscesses:

  • Brush teeth thoroughly to remove as much plaque as possible. Pay attention to the area just under the gums, where plaque can hide.
  • Use fluoride toothpaste to help fight tooth decay.
  • Floss teeth regularly to remove plaque between the teeth.
  • Schedule regular dental appointments for thorough cleaning. A dentist can also remove hardened plaque or tartar, which a person cannot remove with brushing alone.
  • Treat diabetes or any other underlying medical condition that may weaken the immune system and increase the risk of acquiring infections.
  • Seek treatment for cavities as soon as possible, before the bacteria penetrate the deeper structures of the tooth.

A tooth abscess is a collection of pus that forms in response to contracting a bacterial infection inside the tooth, gum, or jaw.

Tooth abscesses can develop due to tooth decay, gum disease, or trauma to the mouth. Without treatment, the bacterial infection that causes the abscess can spread to other parts of the body. This can cause serious complications.

A person who experiences symptoms of a tooth abscess should see their dentist as soon as possible. With the right care, it is possible to treat both the abscess and its underlying cause. Good oral hygiene and regular dental cleaning can help prevent a tooth abscess from forming.