Root canals are most often necessary when decay or a fracture line has reached the nerve of the tooth. Root canal therapy involves removal of the infected or inflamed tissue within the tooth, cleansing and debridement of the canals with small files, disinfection of the canals and pulp chamber before sealing the canals to limit the possibility of future infection. This procedure allows the tooth to heal and alleviates the discomfort caused by an inflamed or infected tooth. Soon after the root canal is performed, the tooth is restored with a dental crown or filling to protect the tooth and restore normal tooth function.