Abscesses are pockets of infected material (pus) contained within a limited area in the body. They may occur in three different areas of the mouth. These types of dental abscesses are identified as follows:

• Tooth abscess. This type of abscess occurs in the bottom-most portion of a tooth – the tip of the tooth root (closest to the jawbone). This is also known as a periapical abscess.
  
  
• Periodontal abscess. This occurs when infection travels from the tooth root into the ligaments (connective tissue) that secure the tooth to the jawbone, and the jawbone socket (alveolar socket) itself. In some cases, a gum abscess develops when food particles become lodged deep in the space between the teeth and gums.
  
  
• Pericoronal abscess. Abscess that occurs when the flap of tissue covering a partially erupted tooth becomes inflamed and infected. It occurs most commonly in the third molars (wisdom teeth).