Sometimes damage to a tooth through breakage or decay can affect dental pulp, which is the soft tissue in the center of the tooth. If this tissue is injured, it can create infection inside the tooth that cannot be fixed through standard filling procedures. A root canal is a procedure to remove infected dental pulp and preserve the inside of the tooth.

Endodontic disease
Dentists can repair damage or deterioration on the outside of a clogged tooth, but when the injury or infection penetrates the inside of the tooth and affects the dental pulp, this is known as endodontic disease and usually requires root canal treatment to save the tooth.

All nerves and blood vessels attached to the inside of the teeth are contained in the dental pulp and extend to the root. The presence of infection in the dental pulp can be done through the root canal and in the critical support structures of your mouth.

If the dental pulp inside a tooth is injured or infected, this can manifest as severe tooth pain, prolonged sensitivity to hot or cold food and drinks, pain to touch, swelling of the jaw and face, pain when eating and discoloration of the tooth.

Fortunately, fully formed teeth do not need dental pulp to function and so the pulp can be removed.

It's more than just a filling.
During root canal treatment, the dentist removes the infected pulp. The root canal is cleaned and sealed to prevent bacteria from entering the region.

Because root canals are most often performed when there has been a large area of caries in the tooth, a crown can be placed on top of the affected tooth to preserve it from an increased risk of fracture.

Root canal treatment may require several appointments, depending on how advanced the infection inside the tooth has become and how complex a treatment is to repair and conserve the tooth.