Exposure reduction in cephalography with a digital photostimulable phosphor imaging system

The effect on the determination of the cephalometric landmarks of exposure reduction using computed radiography with a photostimulable storage phosphor was evaluated. Forty patients attending for regular review were divided into four groups of 10. The first group was exposed to the same amount of radiation as that required for a conventional calcium tungstate screen-film combination. The other three groups were exposed to approximately 50, 20 and 10% respectively of the radiation dose of the first group. Ten dentists determined the landmarks. The coordinates of the points were recorded to measure the consistency of landmark identification. It was found that in comparison with the conventional screen-film system, a substantial reduction of exposure could be achieved with computed radiography for cephalography without clinical detriment.