Department of Experimental Medicine;
Section of Hygiene;
Occupational Medicine and Forensic Medicine;
Second University of Naples;
Naples;
Italy;
Institute for Health Services Research in Dermatology and Nursing;
University Medical Center Hamburg-Eppendorf;
Hamburg;
Germany;
Institution for Statutory Accident Insurance and Prevention in Healthcare and Welfare Services;
Hamburg;
Germany;
ASL Napoli 1;
Naples;
Italy;
Department of Orthodontics;
Second University of Naples;
Naples;
Italy;
HBV; Infection; HBV; Vaccination; Anti-HBs; Titre; Dental; Students;