A Tooth is made up of three layers, namely, enamel, dentin and pulp. Enamel is the most outer, white hard layer and pulp is the most inner, soft tissue layer which contains blood vessels and nerves of tooth. When a tooth gets decayed, and if left untreated the infection spreads from enamel through dentin to pulp causing injury to the nerve and blood supply of the tooth, which results in sensitivity to hot and cold or pain of tooth. This infection can also spread through root canal system of tooth leading to an abcess.
So root canal treatment will help in relieving pain in order to save the tooth by removing the pulp and the decay. The resulting space is filled with special, medicated dental materials. It allows the natural tooth to be retained for its healthy function and esthetics and prevents the removal of a tooth and resulting problem of toothlessness.