When the root of a tooth becomes infected, the infection typically develops unnoticed for a few days or weeks. When located under a filling, this process can go on for even longer, infecting and sometimes destroying the nerve.

The root canal of the infected tooth needs to be immediately treated/removed to prevent the infection from spreading. Depending on the complexity of the case, some emergency root canal treatments may require more than one procedure. The number of appointments will depend on the treated tooth; front teeth have only one root canal while molars have two and in some cases, three roots.

Topical sedation is provided before each root canal treatment procedure the patient has no sensation in the treated tooth. Using specialised dental instruments, the dentist then removes the nerve, completely emptying the tooth canal. Following the application of topical medicine, allowing the place to calm, the canal is filled with gutta-percha, a natural polymer prepared from latex from the percha tree (Palaquium gutta).