1. Department of Oral and Maxillofacial Surgery and Oral Medicine, Faculty of Odontology Malmö University Malmö Sweden
2. Department Clinic‐Surgical Diagnostic and Pediatric Sciences University of Pavia Pavia Italy
3. Private Practice Busto Arsizio Italy
4. Department of Periodontics University of Iowa College of Dentistry Iowa City Iowa USA
5. Department of Periodontics and Oral Medicine University of Michigan School of Dentistry Ann Arbor Michigan USA
6. Department of Periodontics and Preventive Dentistry University of Pittsburgh School of Dental Medicine Pittsburgh Pennsylvania USA