1. Department of Oral Medicine Infection, and Immunity Division of Periodontology Harvard School of Dental Medicine Boston Massachusetts USA
2. Department of Periodontics & Oral Medicine University of Michigan School of Dentistry Ann Arbor Michigan USA
3. Center for clinical Research and evidence synthesis In oral TissuE RegeneratION (CRITERION) Boston USA
4. The Forsyth Institute Cambridge Massachusetts USA
5. Department of Life Health and Environmental Sciences University of L'Aquila L'Aquila Italy