If a canal ever gets infected, which generally occurs when tooth cavities destroy the enamel and dentin, the pulp gets exposed to the outer environment. At this stage, the patient feels an intense pain that might even radiate to the head and ear, sensitivity to hot and cold, and discomfort. If left untreated, an infection occurs causing the death of the pulp and also infection of the surrounding bone. The stage is usually associated with the inability of the tooth to withstand chewing forces. Unless still treated, this pain will likely remain and could result in the tooth eventually falling out.
In order to prevent tooth loss, root canal treatment must be performed. The treatment is designed to clear out diseased material from inside the canal. To perform root canal treatment, an access is drilled into the tooth to allow entry0 into the inner pulp chamber. The diseased pulp is completely removed with special instruments, and the cavity is usually filled and capped with specific inert material.
The success rate of root canal treatment is high. Only 5% of the cases typically require a remedial treatment. Complications usually involve re-infection of the pulp from diseased tissue that was inadvertently left behind. A re-infection of the tooth could mean either another root canal surgery or the loss of the tooth.