1. Department of Periodontics and Community Dentistry; College of Dentistry; King Saud University; Riyadh Saudi Arabia
2. Private Practice; London UK
3. Department of Periodontology; UCL Eastman Dental Institute; London UK
4. Centre for Oral Clinical Research, Institute of Dentistry; Barts and The London School of Medicine and Dentistry; Queen Mary University of London (QMUL); London UK