If your tooth’s nerve chamber becomes infected by decay, root canal treatment is often the only way to save your tooth. Inside your tooth’s hard outer shell is a nourishing pulp of blood vessels, lymph vessels, and nerves. The root canals, which contain the pulp, extend to the bone. Deep tooth decay, or an injury, can cause serious damage and infection to the pulp’s nerves and vessels. Root canal, or endodontic, treatment cleans out the infected pulp chamber ad repairs the damage. Some indications of the need for root canal treatment may be Spontaneous pain or throbbing while biting. Sensitivity to hot and cold foods.