Prosthetic joints are one of the great advances of modern medicine. They improve patients’ quality of life by providing pain relief, mobility, and independence. There are already more than 7 million people with prosthetic joints in the United States,1 and this number is increasing rapidly. From the 1970s through the 1980s, orthopedic surgeons began to call for dentists to give antibiotic prophylaxis (AP) to patients with prosthetic joints undergoing invasive dental procedures (IDP). In 1988, the American Dental Association (ADA) sponsored a workshop that concluded that scientific data were inadequate to support the need for or effectiveness of AP and that the decision to use or not use AP should be up to the dentist’s clinical judgement in consultation with the orthopedist.