In a previous survey, we analyzed a questionnaire to 220 patients, who underwent cardiac surgery with insertion of prosthetic heart valves in the period 1978-1982. Of the 147 patients with their own natural teeth, 136 gave us permission to contact their regular or casual dentists. Of the 108 dentists (79%), who responded to a questionnaire, two thirds were well aware that their patients had prosthetic heart valve and the vast majority of dentists believed that antibiotic prophylaxis is justified in connection with (certain) dental procedures. However, only 15 dentists (14%) prescribed prophylactic antibiotics, i.e. before scaling. The dosage route, frequency and duration of antibiotic administration used by more than half of the dentists was not in accordance with modern principles of antibiotic prophylaxis to prevent bacterial endocarditis. Proposals for antibiotic regimens have to be linked to better education/information of the patients, doctors and dentists and should be linked to recommendations to ensure the highest level of dental care in risk patients.