Clinical comparison of conventional and rare earth screen-film systems for cephalometric radiographs.

This study compared cephalometric and P-A skull films taken with conventional (CaWO4) screens and rare earth screens. Patient exposure was reduced by 17 to 55 percent on two different x-ray machines by the use of rare earth screens. Results from 130 clinical evaluations showed that the diagnostic quality of radiographs taken with either system was roughly comparable. This presents a persuasive argument for the use of rare earth screens since the diagnostic quality of the films can be maintained while significantly reducing the patient's exposure to radiation.