Oral abscess


An abscess in the mouth is defined as an accumulation of pus located in the oral cavity. An oral abscess is characterized by a pus-filled, heated, painful and pressure-sensitive swelling in the oral cavity. The “boil” can be located in different parts of the mouth. As a preliminary stage, a pasty swelling, infiltrate or oedema often develops in the mouth, which carries the risk of abscess formation. These preliminary stages can be distinguished from the actual accumulation of pus.

Causes of the abscess

In particular, people with a weakened immune system are at risk of developing oral abscesses. Tiny injuries in the mouth create entry points for bacteria. These can trigger inflammation and cause the formation of an abscess.

This can theoretically happen anywhere in the mouth. In addition, oral abscesses can be caused in the mouth. These are usually caused by an inflamed tooth bed, a gum pocket, a wisdom tooth that has not yet broken through, a dental cyst or a dead tooth.

When a tooth dies, toxins are released by the bacteria that metabolise the tissue. If there is also dental caries, it is easier and simpler for the bacteria to penetrate. As a result, inflammation can develop and the pulp can die.

If this area is not well supplied with blood, cells decay and are broken down. Eventually an abscess in the mouth – an abscess of the jaw – can develop. An inflamed tip of the tooth root can also result in abscesses in the jaw. This can be explained by the increased activity of the body’s own defence cells and the degradation of the jawbone. In addition, underlying diseases such as diabetes mellitus or cancer can promote the development of oral abscesses.


If an abscess forms in the mouth, it may initially be symptom-free. If it grows, however, the typical signs of inflammation may appear at a certain size. These include swelling, redness, pain, warming and possibly a functional impairment.

If left untreated, the abscess can lead to complications. If fever occurs, this is a warning sign that the bacteria have now entered the bloodstream. There is a risk of blood poisoning, which requires emergency medical treatment.

You can also read about other symptoms of an abscess in the following article: Symptoms of an abscess You can also read about other symptoms of an abscess in the following article: Symptoms of an Abscess

  • In a mature abscess, pus can come out. This can lead to a bad, unpleasant smell and taste. – The inflammation can spread further and attack other neighbouring tissue.

How contagious is an abscess?

Since it is a bacterial infection, a mouth abscess is theoretically contagious if someone comes into direct contact with the pathogen. Therefore, as a precautionary measure, kissing should be avoided in the case of an existing mouth abscess as long as the pathogen can still be detected. You should also not share a toothbrush – regardless of whether or not an abscess is present.