1. Division of Periodontology and Implant Dentistry, Faculty of Dentistry The University of Hong Kong, Prince Philip Dental Hospital Hong Kong SAR China
2. Department of Dental Medicine, Division of Oral Diagnostics and Rehabilitation Karolinska Institute Huddinge Sweden
3. Department of Oral and Maxillofacial Surgery Falun Hospital Falun Dalarna Region Sweden
4. Department of Oral Medicine & Radiology, King George's Medical University Lucknow India