A periapical abscess is an infection in the jaw at the tip of the root.
This occurs after the pulp (nerve) of the tooth becomes infected or damaged. It is usually caused by decay or because of an accident (nerve damage). The tooth requires a root canal treatment, apicoectomy or extraction and possibly antibiotics. An abscessed tooth is usually sensitive or painful and can be seen on an x-ray.
Apicoectomy – Root tip surgery
During root canal (endodontic) treatment, infected nerve tissue is removed from inside the tooth (canals). Sometimes infection may remain in the side branches causing re-infection. Apicoectomy is a surgical procedure that attempts to remove infection from the tip of the tooth. This surgery is more difficult to perform in the back (molar) teeth because of difficulty in surgical access and complexity of multi-rooted teeth. Sometimes this procedure is not indicated, the infected tooth may need to be extracted and maybe replaced by an implant.
The dark area is the inflammation site at the root tip and the white is root / root tip filling material.
