1. Department of Prosthetic Dental Sciences; College of Dentistry, King Saud University; Riyadh Saudi Arabia
2. Department of General Dentistry; Eastman Institute for Oral Health, University of Rochester; Rochester NY USA
3. Dental Health Department; College of Applied Medical Sciences, King Saud University; Riyadh Saudi Arabia
4. Department of Periodontology, School of Dental Medicine; Stony Brook University; New York NY USA
5. Department of Oral Surgery and Implant Dentistry; Dental School Frankfurt; Frankfurt Germany