Rare earth filters for intraoral radiography: exposure reduction as a function of kV(p) with comparisons of image quality.

Radiographs of phantoms were produced using E-speed film and various rare earth X-ray beam filters. The rare earth filters considerably reduced the amount of radiation needed to produce diagnostic quality images and, in many cases, improved image quality. These filters can be implemented easily and inexpensively in a clinical setting, resulting in radiation exposure reductions of up to 71%.