1. Section of Periodontics; Department of Dentistry and Maxillofacial Surgery; School of Dentistry; Sapienza University of Rome; Rome Italy
2. Department of Periodontology; Faculty of Dentistry; Istanbul University; Istanbul Turkey
3. Department of Odontostomatological; Orthodontic and Surgical Disciplines; Second University of Naples; Naples Italy
4. Department of Histology and Embryology; Faculty of Medicine; Bezmialem Vakif University; Istanbul Turkey
5. Division of Periodontology; College of Dentistry; The Ohio State University; Columbus OH USA