Dentists, hygienists and assistants wear surgical gloves, eye glasses and masks to prevent microorganisms from being transferred during dental procedures. Dental instruments are heat sterilized between each patient to protect against cross-contamination. Precautions are taken in handling and disposing hazardous waste materials in the dental office. Waterlines in the dental office are also flushed at the beginning and end of each day, and between patients. This ensures there is no backwash into the next patient's mouth. Don't hesitate to ask your dentist about any of these precautions.