One of the newest techniques around, digital x-rays are beginning to appear in dentists’ offices. In the digital variety, the x-rays hit a flat electronic pad or sensor instead of film, and the image is sent electronically to a computer where it appears onscreen and is printed out or stored. Digital x-rays allow digital comparison of images with previous images. In this process, called subtraction radiography, the computer compares two images, subtracts out everything that is the same and presents a clear image of anything that is different. Tiny changes can be caught earlier with digital-subtraction radiography.