Root canals are valuable dental procedures used to treat and preserve teeth with badly infected roots. The pulp is the live portion of the tooth that extends into the root and contains nerve endings and tissues. When it becomes infected, patients can experience pain, swelling and even total tooth loss unless treated. Root canal treatment removes the damaged part of the tooth and infected nerve tissue. The organic portion of the tooth that remains may be restored using a cap or crown that provides a natural appearance and normal tooth function.