An extra-oral dental imaging apparatus for obtaining an image from a patient has a radiation source and a digital imaging sensor that provides, for each of a number of image pixels, at least a first digital value according to a count of received photons that exceed at least a first energy threshold. A mount supports the radiation source and the digital imaging sensor on opposite sides of the patient's head. There can be a computer in signal communication with the digital imaging sensor for acquiring one or more two-dimensional images.