The treatment of reproducible inflammation of the pulp preserves the pulp as much as possible. Root canal treatment is preferred in cases of severe pulpal lesions, severe inflammation, or necrosis of the pulp leading to periapical disease. Another principle of treatment for endodontics and periapical disease is to preserve as much healthy tooth tissue as possible, and another is to preserve the affected tooth as much as possible. Many patients with recurrent inflammation of the tooth, did not try to treat or extracted in some unregulated hospitals is a pity, through the root canal or surgical treatment can save the affected tooth, to maintain the integrity of the masticatory organs, the exercise of good function, the principle of its treatment is to remove the infection in the root canal as the goal of the treatment process the patient has the right to know, while taking into account the patient’s general health, the complexity of the root canal treatment and the cost of the treatment should be clearly explained to the patient. The complexity and cost of root canal treatment should be clearly explained to the patient.