1. Department of Oral Medicine and Diagnostic Sciences AlFarabi Colleges for Dentistry and Nursing Riyadh Saudi Arabia
2. Department of Oral Medicine, Faculty of Dentistry Sana’a University Sana’a Yemen
3. Department of Prosthetic Dental Sciences AlFarabi Colleges for Dentistry and Nursing Riyadh Saudi Arabia
4. Department of Preventive Dental Sciences AlFarabi Colleges for Dentistry and Nursing Riyadh Saudi Arabia
5. Department of Oral and Maxillofacial Surgery AlFarabi Colleges for Dentistry and Nursing Riyadh Saudi Arabia
6. Department of Prosthodontics, Faculty of Dentistry Thamar University Dhamar Yemen
7. Department of Epidemiology, Biostatitics and Occupational Health McGill University Montreal Québec Canada