Because of the difficulty of identifying infected persons, current recommendations for infection control are to treat all patients as if they are infected with blood-borne pathogens such as human immunodeficiency virus (HIV) and the hepatitis viruses. Dentists' compliance with these recommendations has been investigated previously, however, there are few data related to orthodontists. The objective of this study was to measure the proportion of orthodontists who report the use of recommended infection control procedures and to compare the infection control practices of orthodontists and general dentists. A mailed survey with three follow-up attempts was administered to all orthodontists and general dentists in Ontario (N = 5441) in 1994. There were significant differences in the routine use of gloves (orthodontists 85%, general dentists 92%); masks (orthodontists 38%, general dentists 75%); protective eyewear (orthodontists 60%, general dentists 84%); changing gloves after each patient (orthodontists 84%, general dentists 96%); and heat sterilization of handpieces (orthodontists 57%, general dentists 84%). Hepatitis B virus (HBV) vaccination of all clinical staff was reported by 46% of orthodontists, compared with 61% of general dentists (p