Public Act No. 423 and Public Act No. 30 allows a registered dental hygienist under the direct supervision of a dentist, the expanded duties to administer intraoral block and infiltration anesthesia or nitrous oxide analgesia to a patient who is 18 years of age or older. In order to administer local anesthesia or nitrous oxide, the hygienist must have completed a Department of Community Health-approved training program, passed a state or regional board administered written exam within 18 months of taking the approved course, and possess current certification in basic or advanced cardiac life support.