A root canal is a dental procedure used to treat an infection that has reached the pulp inside a tooth. During the procedure, the infected pulp is removed, the tooth’s interior is cleaned, and it’s sealed to prevent further infection. However, in some cases, an abscess may persist even after a root canal has been completed.

A persistent abscess after a root canal is an infection that lingers, causing ongoing pain and discomfort in the jaw. This can happen because bacteria were not entirely eradicated during the root canal procedure or because new bacteria entered the tooth afterward.