Endodontics is the dental specialty that deals with the nerves of the teeth. Root canals are probably the most notorious procedure in dentistry and the most common procedure relating to endodontics. When a tooth becomes infected it is usually related to the nerves in the root of the tooth. The infected nerves need to be removed. If left untreated an infection can turn into an abscess, which is a much more serious problem that includes bone loss in the jaw.
"Root canal" has become a scary term for dental patients to hear, but the benefits of the procedure and advances in dental technology have made it much less "scary". Local anesthetics and proper pain medication allow the procedure to be performed with little to no pain in most cases.