1. Department of Surgery, Medicine and Experimental SciencesUniversity of Sassari Sassari Italy
2. WHO Collaboration Centre for Epidemiology and Community DentistryUniversity of Milan Milan Italy
3. Klinik für Zahnerhaltung, Präventiv‐und Kinderzahnmedizin Zahnmedizinische Kliniken (ZMK)University of Bern Switzerland
4. IRCCS “Ca Granda‐Ospedale Maggiore”University of Milan Milan Italy
5. Department of BiomedicalSurgical and Dental Science, University of Milan Milan Italy