Affiliations: Department of Radiology, Faculty of Dentistry, Hamadan
University of Medical sciences, Hamadan, Iran | Department of Medical Physics, Faculty of Medicine,
Hamadan University of Medical sciences, Hamadan, Iran | Department of Medical Physics, Royal Adelaide
Hospital, Adelaide, South Australia, Australia | School of Mechanical Engineering, Shiraz University,
Shiraz, Iran | Department of Epidemiology and Biostatistics, Research
Centre for Health Sciences, Faculty of Health, Hamadan University of Medical
Sciences, Hamadan, Iran
Note: [] Corresponding author: Amir Abbas Jafari, Department of
Radiology, Faculty of Dentistry, Hamadan University of Medical sciences,
Hamadan, Iran. Tel.: +98 9183111790; E-mail: [email protected]
Abstract: The effectiveness of added filters including conventional and rare
earth materials for dental radiography tasks was investigated using a
simulation approach. Current study focuses on the combination of a range of
various filters to investigate the reduction of radiation absorbed dose and
improving the quality of a radiography image. To simulate the X-ray beam spectrum, a MCNP5 code was applied.
Relative intensity, beam quality, and mean energy were investigated for a
typical dental radiography machine. The impact of different rare-earth
materials with different thicknesses and tube voltages on the X-ray spectrum
was investigated. For Aluminum as a conventional filter, the modeled X-ray spectra and
HVL values were in a good agreement with those reported by IPEM. The results
showed that for a 70 kVp voltage, with an increase of the thickness and atomic
number of a given added filters, an increase of HVL values were observed.
However, with the increase of the attenuator thickness, X-ray beam intensity
decreases. For mean energy, different results were observed. It was also found
that rare earth made filters reduce high energy X-ray radiation due to k-edge
absorption. This leads to an ideal beam for intra-oral radiography tasks.
However, as a disadvantage of rare earth added filters, the reduction of the
tube output levels should also be considered.
Keywords: Dental radiography, diagnostic X ray, rare earth elements
