An abscess is a localized collection of pus in an infected area. Pus consists of bacteria, dead cells and other microorganisms.
The two main types of abscesses that form in the oral cavity are:
Dental abscess. This is an inflammation of the dental pulp. It is generally a consequence of dental caries, or tooth decay. The pus forms around the tip of the tooth's root. This is defined as periapical abscess.
Gingival abscess. This is an inflammation of the gums. It is the result of a common gum disease called periodontitis. Pus forms in the crevices between the tooth and the gums caused by periodontitis. The technical name is periodontal abscess.
On rare occasions, abscesses can form in the jawbones.
The typical symptoms associated with abscess are pain, swelling, and sensitivity of the area where the abscess occurs. Sometimes, these can be symptoms of underlying diseases. For example, swelling may indicate a problem of the salivary glands. Dental sensitivity can also be a sign of bruxism--a clenching and grinding of teeth that usually goes unnoticed.