An abscess is a collection of suppurative liquid in tissue in connection with an inflammation.

• Parodontal abscess – concerning parts of the parodontium;
• Pericoronal abscess – arises in the vicinity of a partially displaced tooth;
• Periapical abscess – arising at the root tip of an avital tooth;
• Gingival abscess – limited to the gums.

Two conditions must prevail in an abscess:

1. Bacteria have entered the tissue.
2. The inflammatory tissue liquid cannot drain off.

Possible entry portals for bacteria are: deep parodontal pockets, the roots of teeth with dead pulpa, the mucosa hoods of partially retained teeth.