Culture conditions for efficient recovery of bacteria from infected dental root canals.

For better bacterial recovery from endodontic lesions, several bacterial culture conditions were studied. Samples taken from endodontic lesions of 26 freshly extracted teeth, and the bacterial growth was determined in 11 kinds of growth media under aerobic (in air with or without addition of 5% CO2) or anaerobic conditions (in an anaerobic glove box). Among the media tested, bacteria of endodontic lesions were most efficiently recovered in brain heart infusion medium containing 4% sheep blood (BHI-Blood) under anaerobic conditions. For routine dental practice, serum can be substituted for blood which makes the media opaque, resulting in clear media, and thus bacterial growth can be judged more easily.