[Are additional filters made of niobium superior to the copper filter in dental radiology?].
At a dental X-ray unit the effect of an additional filter made of niobium has been tested in the molar region of the mandible with respect to dose reduction. It has been compared against the effect of an additional filter made of copper. With regard to the same dose at the film, radiation dose at the surface of the patient proved to be slightly more reduced after application of the copper filter than after application of the niobium filter. Radiographs have been made by exposure of intraoral dental films (Kodak film Ultra Speed D) together with a hydroxyapatite step-wedge. Measurements of optical density resulted in the same values after application of the copper filter and the niobium filter, respectively. Reduced image contrast due to application of one of these additional filters proved to be helpful. In short, an additional copper filter placed in the X-ray beam shows identical or better results when compared against an additional filter made of niobium.
Cordt
I
I
Strahlenbiologisches Institut, Universität Zürich.
Engelke
W
W
D003300:Copper; D005069:Evaluation Studies as Topic; D005374:Filtration / Q000295:instrumentation; D006801:Humans; D008961:Models, Structural; D009556:Niobium; D011829:Radiation Dosage; D011861:Radiography, Dental / Q000295:instrumentation*; D014963:X-Ray Intensifying Screens
D009556:Niobium; D003300:Copper
Sind Zusatzfilter aus Niobium in der zahnärztlichen Radiologie dem Kupferfilter uberlegen?