1. Health Radiation Research Department, National Centre for Radiation Research and Technology, Atomic Energy Authority, Cairo, Egypt
2. Oral and Dental Biology Department, Faculty of Dental Medicine for Girls, Al-Azhar University, Cairo, Egypt
3. Oral Medicine, Periodontology, Diagnosis and Radiology Department, Faculty of Dental Medicine for Girls, Al-Azhar University, Cairo, Egypt
4. Cytology and Histology Department, Faculty of Veterinary Medicine, Cairo University, Cairo, Egypt