A routine dental X-ray is an internal image of your teeth and jaws. Dentists use these images to examine structures that they cannot see from the outside, including your jaw, nerves, sinuses, and the roots of your teeth in order to detect early signs of tooth decay, observe overall oral health, and monitor jaw and tooth formation in adolescents. This practice also allows dentists to discover problems like bone loss from periodontal disease, signs of issues with the roots of the teeth, and even changes caused by disease of the body.