What Is A Periapical Abscess?

A periapical abscess is a type of dental abscess and is one of the most common tooth disorders. In simplest terms, it is a collection of pus at the end of the tooth's root. Specifically, a periapical abscess can be defined as a collection of pus located at the tooth's root that is caused by bacteria and infection. Studies reveal that periapical abscess can appear only if there are bacteria within the tooth canal.


A periapical abscess is a localized and often acute collection of pus around the apex or roots of a nonvital tooth. It is different from periodontal abscesses, which appear in the gums. The infection slowly builds up and accumulates pus until the issue breaks open and discharges pus. Pus, the whitish-yellow substance coming out from the lesion, is actually composed of dead white blood cells sent by the body to fight bacteria, dead tissue, bacteria, and phagocytes. If left untreated, it causes bad taste and foul smell in the mouth. It also comes with intense, throbbing, and constant pain due to sensitivity to pressure, percussion, and heat.

Its Causes

The cause of periapical abscesses is death of tissues in the root canal. Tooth cavity is the earliest cause of periapical abscess because tooth decay is the start of developing an infection that will eventually kill the pulp or tissues along the tooth canal. The presence of bacteria in the root canal leads to infection until the tissues or pulp die off. Depending on the location of the problem tooth, the infection may spread further to affect the surrounding bone and nearby tissues. This is why you may also experience throbbing pain and swelling in the jaw, around the cheeks, or in the floor of the mouth. Excessive swelling and accumulation of pus can also lead to high fever.


While the periapical abscess eventually results to presence of gum boils as the drainage site for pus, your dentist may not diagnose it from a dental image. He or she will have a definitive diagnosis only after microscopic examination and/or thermal testing. Some of the possible treatments are pus drainage, antibiotics, endodontic therapy, root canal treatment, or tooth extraction and replacement.

The presence of a periapical abscess is one of the earliest signs that it is time to visit your dentist. You can relieve the pain but avoid self-medication. It is best to go to a family dentistry clinic for proper diagnosis and treatment for periapical abscesses.