Abscesses of the Periodontium

A periodontal abscess, a lateral abscess or parietal abscess, is collection of pus located within the periodontium tissues. A periodontal abscess is different from a periapical abscess, which is quite common, as it occurs next to a tooth. A periapical abscess occurs when there is a spread of infection from a dead tooth. Because of this, the term lateral abscess is sometimes used. When compared to a periapical abscess, a periodontal abscess is usually next to a living tooth. Abscesses of the periodontium are considered to be am acute bacterial infection, a classification primarily used due to the location.

Signs & Symptoms

The most common symptom of a periodontal abscess is pain which is brought on suddenly, and worsens when biting down on the impacted tooth. The tooth can also have a sensation of being slightly raised or more prominent. The periodontal abscess can cause the tooth to move, and the lesion can also damage the periodontal ligament and the alveolar bone. The pain experienced by most patients is deep and throbs. In the early stages, the oral mucosa covering the periodontal abscess is red, swollen and painful to the touch. Because the mucosa stretches over the abscess, the surface may appear to be shiny.

Once pus forms, the pressure increases and becomes more painful until the abscess spontaneously drains and relieves the discomfort. When the pus drains, there is often a bad taste and odor in the mouth. The drainage commonly occurs within the periodontal pocket. The local anatomic factors determine the spread of the pus. There may also be a systemic upset, which involves fever and pain.


A periodontal abscess often happens as a complication of advanced periodontal disease. Periodontal pockets typically contain bacteria, dental plaque, and subgingival calculus. Periodontal pathogens often make their way into the soft tissues, however, the immune system usually fights off any infection. A periodontal abscess indicates that the normal balance is off. When bacteria invade and multiply within the soft tissue of the periodontal pocket, there is an inflammatory response. A pus-filled abscess forms as a response from the immune system working to prevent the spread of infection.

The opening of the periodontal pocket allows communication with the oral environment. When the periodontal pocket opening is obstructed, however, which is common with deep pockets, plaque and calculus can be easily trapped inside. Food packing, often caused by incompatible contact points with dental restorations, can also act as an obstruction to the periodontal pocket. An abscess can also be caused by incomplete scaling of the periodontal pocket. Following a scaling procedure, the gingival cuff closes tightly around the tooth. This can trap the remaining bacteria in the pocket.

A penetrating injury to the gingiva, such as a fish bone, toothpick or other firm object, can allow bacteria to get into the tissues. Other possible causes include trauma to the tissues or excessive pressure from an orthodontic treatment.

Systemic immune problems, such as diabetes, can give patients a predisposition for the formation of a periodontal abscess.

Perforation, which is performed during a root canal, can also cause a periodontal abscess.

While it is challenging to differentiate a periodontal abscesses from a periapical abscesses, it is critical to make the correct diagnosis because of the varying treatment plans.