Hepatitis B is an infectious disease to which dentists are susceptible. The main aim of this study was to determine the level of antibody titer and immunity in vaccinated Iranian general dentists. A total of 861 general dentists were invited to participate in this study; 598 persons who could recall their history of vaccination and consented to have blood samples taken were recruited. Demographic and work-related data were recorded, and anti-Hepatitis B surface antigen (anti-HBs-Ag) evaluations were measured using the enzyme-linked immunosorbent assay (ELISA). Of the 598 participants, 35 (5.9%) were nonimmune (anti-HBs <10 IU/l), 101 (16.9%) were relatively immune (anti-HBs = 10-99 IU/l), and 462 (77.3%) were completely immune (anti-HBs > or =100 IU/l). Only 218 (36.5%) of the dentists knew their HBs antibody titer. Fourteen (2.3%) persons reported receiving one dose and 65 (10.9%) had received two doses. The number of those who had received the three recommended doses totaled 519 (86.8%), 491 (82.1%) of them receiving their vaccine on schedule. Age, city, pack-years of smoking, years of smoking, and the interval between the last vaccination and the commencement of the study had a significant relationship to the antibody titer level, whereas sex, marital status, place of practice, smoking, and vaccination schedule were not related. Only 36.5% of the general dentists had checked their antibody titer. We, therefore, recommend that dentists, as a potential high-risk group, should know their level of anti-HBs antibody titer so that those who require revaccination can get treatment.