A<unk>  most commonly occurs as a complication of advanced<unk>  disease (which is normally painless). A<unk>  pocket contains dental plaque, bacteria and subgingival calculus.<unk>  pathogens continually find their way into the soft tissues, but normally they are held in check by the immune system. A<unk>  represents a change in this balance, related to decreased local or systemic resistance of the host. An inflammatory response occurs when bacteria invade and multiply within the soft tissue of the gingival crevice/periodontal pocket. A pus-filled abscess forms when the immune system responds and attempts to isolate the infection from spreading. Communication with the oral environment is maintained via the opening of the<unk>  pocket. However, if the opening of a<unk>  pocket becomes obstructed, as may occur if the pocket has become very deep (e.g. with furcation involvement), then plaque and calculus are trapped inside. Food packing may also obstruct a<unk>  pocket. Food packing is usually caused by failure to accurately reproduce the contact points when dental restorations are placed on the interproximal surfaces of teeth. Another potential cause occurs when a<unk>  pocket is scaled incompletely. Following this procedure, the gingival cuff tightens around the tooth, which may be enough to trap the bacteria left in the pocket. A gingival retraction cord which is accidentally left in situ is an occasional cause of a<unk> . Penetrating injury to the gingiva--for example, with a toothbrush bristle, fishbone, toothpick or<unk>  instrument--may inoculate bacteria into the tissues. 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. Occlusal overload may also be involved in the development of a<unk> , but this is rare and usually occurs in combination with other factors. Bruxism is a common cause of excessive occlusal forces. Systemic immune factors such as diabetes can predispose a person to the formation of<unk> es. Perforation of a root canal during endodontic therapy can also lead to a<unk> .
Periodontal abscess
Dental abscess
Dental plaque
Gingival cyst
Posthitis
Oral mucocele
Salivary gland fistula
Cuffitis