For most people, a complete radiographic survey should be done every 3 years, and a "check up" or "recall" set every 6 to 12 months. A complete set of x-rays is estimated to expose you to the same amount of radiation you get on a flight from San Francisco to Seattle. Doctors use x-rays as an aid in diagnosing problems. Without x-rays "seeing" the problem will be difficult if not impossible.