Dental hygienists are highly trained, college-educated health care providers specializing in the prevention and early detection of tooth and gum disease. They are qualified to perform examinations, remove calcified deposits, apply fluoride treatments, and educate patients in proper methods of dental hygiene. They are also trained to remove sutures, take radiographs (x-rays), and perform other diagnostic tests. The work of dental hygienists is closely regulated with written examinations and licensing required in all states. In California, Registered Dental Hygienists may give local anesthesia when required for patient comfort.