1. Department of Surgery, Microsurgery and Medical Science, School of Dentistry, University of Sassari, Italy
2. WHO Collaborating Centre of Milan for Epidemiology and Community Dentistry, University of Milan, “S. Paolo Hospital”, Milan, Italy
3. School of Dentistry, Sapienza, University of Rome, Italy
4. Department of Chemistry, University of Sassari, Italy
5. Italian Minister of Health General Office, Rome, Italy
6. Department of Cariology, Institute of Odontology, The Sahlgrenska Academy, University of Gothenburg, Sweden