1. Division of Oral Biology, Leeds School of Dentistry, St. James University Hospital, University of Leeds, Leeds LS9 7TF, UK
2. Department of Endodontics, Faculty of Dentistry, Assiut University, Assiut 83523, Egypt
3. Department of Dentistry, School of Health Sciences, University of Brasilia, Brasilia 70910-900, Brazil
4. Oral Surgery, Life Course and Medical Science, Liverpool L8 7SS, UK
5. Oral Biology Department, Faculty of Dentistry, King Abdulaziz University, Jeddah 21589, Saudi Arabia
6. Department of Endodontics, Faculty of Dentistry, Ain Shams University, Cairo 11566, Egypt
7. Endodontics, Conservative Dentistry Department and Tissue Engineering Laboratories, Faculty of Dentistry, Alexandria University, Alexandria 21527, Egypt
8. Department of Oral Pathology, Faculty of Dentistry, Suez Canal University, Ismailia 8366004, Egypt