The oral mucosa covering an early periodontal abscess appears erythematous (red), swollen and painful to touch.

[7] A periodontal abscess represents a change in this balance, related to decreased local or systemic resistance of the host.

[9] A pus-filled abscess forms when the immune system responds and attempts to isolate the infection from spreading.

[13] Food impaction is usually caused by failure to accurately reproduce the contact points when dental restorations are placed on the interproximal surfaces of teeth.

[16] Trauma to the tissues, such as serious impact on a tooth or excessive pressure exerted on teeth during orthodontic treatment, can be a possible cause as well.

[17] Occlusal overload may also be involved in the development of a periodontal abscess, but this is rare and usually occurs in combination with other factors.

Antibiotics are generally reserved for severe infections, in which there is facial swelling, systemic upset and elevated temperature.

[20][21] Ideally, the choice of antibiotic is dictated by the results of microbiological culture and sensitivity testing of a sample of the pus aspirated at the start of any treatment, but this rarely occurs outside the hospital setting.

Other measures that are taken during management of the acute phase might include reducing the height of the tooth with a dental drill, so it no longer contacts the opposing tooth when biting down; and regular use of hot salt water mouth washes (antiseptic) that encourages further drainage of the infection.

The management following the acute phase involves removing any residual infection, and correcting the factors that lead to the formation of the periodontal abscess.