We studied 1309 dental professionals (1132 dentists, 131 hygienists, and 46 assistants) without behavioral risk factors for the acquired immunodeficiency syndrome (AIDS) to determine their occupational risk for infection with human immunodeficiency virus (HIV). Subjects completed questionnaires on behavior; type, duration, and location of their dental practice; infection-control practices; and estimated numbers of potential occupational exposures to HIV. Serum samples were tested for antibodies to HIV and to hepatitis B surface antigen (unvaccinated subjects). Fifty-one percent of the subjects practiced in locations where many cases of AIDS have been reported. Seventy-two percent treated patients who had AIDS or were at increased risk for it. Ninety-four percent reported accidental puncturing of the skin with instruments used in treating patients. Adherence to recommended infection-control practices was infrequent. Twenty-one percent of unvaccinated subjects had antibodies to hepatitis B surface antigen. Only one dentist without a history of behavioral risk factors for AIDS had serum antibodies to HIV. We conclude that despite infrequent compliance with recommended infection-control precautions, frequent occupational exposure to persons at increased risk for HIV infection, and frequent accidental puncturing of the skin with sharp instruments, dental professionals are at low occupational risk for HIV infection.