Dose reductions in dental X-ray imaging using Medipix

We have measured the noise power spectra for a commercial CCD device, for dental X-ray imaging, and an X-ray photon counting chip, Medipixl. This quantity provides a measure of the noise propagation characteristics in both types of detector and coupled with the measurement of the modulation transfer function demonstrates the large dose reductions that are possible with the photon counting system compared to the CCD.