In connection with ageing of population and an increasing number of older patients visiting the dental practice with multiple diseases, special prevention of possible medical complication during dental treatment is necessary. The advances in dentistry increase the chance of these complications. There is however no consensus about history taking in dental practice. For getting the maximum amount of information about the patient's health a Risk-Related Medical History (RRMH) patient-administered is proposed, that is checked by the dentist. The RRMH was composed in accordance with the modified ASA physical risk score. It allows to dyfine general patient's physical condition and to advise measures for prophylaxis of medical complication. The medical questionnaire showed a high sensitivity and specificity. In a study among 5000 patients the results of this history was analysed. The RRMH is simple and comfortable, it allows to obtain relible medical information in short time both for the dentist and for the patient.