Americans often go to their doctor and dentists when they are not sick. They hope to prevent being sick by having their teeth cleaned and their health checked. Therefore, they see the doctor and dentist for check-ups. Doctors check their breathing, heartbeat, ears, eyes, and throat, their weight, take samples of patient's fluids to run tests, and look for signs of more serious illnesses. Dentists clean a patient's teeth, and take x-rays to see if any teeth are going bad. More and more, Americans and the people who take care of their health are practicing this kind of preventive medicine.