Inside the tooth's dense outer shell is a nourishing pulp of nerves, blood vessels and lymph vessels. The root canals contain the pulp and extend through the root to the bone.

Deep tooth decay or an injury can cause serious damage to these vital tissues. Teeth with large fillings or crowns can also have underlying damaged pulps that are vulnerable to bacterial infection. Root canal, or endodontic treatment cleans out the infected pulp chamber and seals it off with a filler material.

Some indications that you may need root canal therapy include:

• Sensitivity to hot and cold liquids, especially for prolonged periods of time (greater than 30 seconds)
• Pain or throbbing when chewing
• Extensive decay or injury that creates an abscess (infection) in the bone
• Pain at night or while lying down

Several diagnostic tests can be performed to determine if this treatment is needed. An X-ray is taken to evaluate the roots and bone for decay and signs of an abscess.

Root canal therapy involves several steps:

• After the tooth is anesthetized, an opening is made through the crown into the pulp chamber.
• The length of the root canals is determined as well as how many canals are present.
• Unhealthy pulp is removed. Canals are cleaned, shaped and irrigated with antibacterial rinses.
• The canals are dried, filled and sealed. Often a post may be added for structural support or to help retain restorative materials.
• The access opening is sealed with a temporary material. A full coverage crown is recommended to protect the tooth from biting forces and possible fracture.