S M J Mortazavi1, S A R Mortazavi2, Maryam Paknahad3. 1. Diagnostic Imaging Center, Fox Chase Cancer Center, Philadelphia, PA 19111, USA; Ionizing and Non-ionizing Radiation Protection Research Center (INIRPRC), Shiraz University of Medical Sciences, Shiraz, Iran. 2. Student of Research Committee, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran. 3. Oral and Dental Disease Research Center, Oral and Maxillofacial Department, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran. Electronic address: paknahad@sums.ac.ir.