1. Department of Family and Community Medicine; Faculty of Medicine; King Saud University; Riyadh Saudi Arabia
2. College of Dentistry; Dar Al Uloom University; Riyadh Saudi Arabia
3. Dr. Abdulaziz Al Ajaji Dental Polyclinics; Riyadh Saudi Arabia
4. Department of Biochemistry; College of Science; King Saud University; Riyadh Saudi Arabia