The fundamental goal of dental treatment is rehabilitation of oral health thus various dental treatment are done. Most of the dental procedures are not life threatening but patients who are medically compromised are exceptional. Fortunately systemic disease can be easily diagnosed by medical insurance(medicare) or annual medical check examination in Korea. Diseases which were fatal at the past are successfully treated nowadays and consequently the population of the elder increases. As the population of elder increases, patients who need medical care as well as dental patient with compromised medical condition increases. It is essential to find out if the patient has any systemic disease. Consultant to the appropriated physician of medically compromised patients? is demanded and also for a successful dental treatment, deep knowledge of the systemic disease is necessary.