1. Department of Periodontology, Tufts University School of Dental Medicine, Boston, MA, USA
2. Department of Diagnostic Sciences, Division of Oral and Maxillofacial Pathology, Tufts University School of Dental Medicine, Boston, MA, USA
3. Periodontology and Prosthodontics, Ospedale Odontoiatrico George Eastman, Rome, Italy
4. Periodontics and Community Dentistry, King Saud University, Riyadh, Kingdom of Saudi Arabia
5. Department of Preventive Dentistry, Prince Sattam bin Abdulaziz University, Riyadh, Kingdom of Saudi Arabia