Detection frequencies and the colony-forming unit recovery of oral treponemes by different cultivation methods

Selected media were compared for primary isolation and detection of oral treponemes from clinical samples. Forty-eight subgingival plaque samples from 45 patients suffering from periodontitis were anaerobically cultivated for 2 weeks at 37 degrees C. Of the 9 media studied, Medium 10 (M10), which was supplemented with 10% rabbit serum and incubated using the plate-in-bottle method, supported the highest colony-forming units of the anaerobes. The treponemal colonies were detected at least on one medium from 83% of the subgingival plaque samples. The new oral spirochete medium in an anaerobic chamber supported the highest detection frequency of the oral treponemes (64% of samples); however, M10 in the plate-in-bottle was found to produce the highest colony-forming unit recovery of the oral treponemes (median 3.6% of the total colony-forming units). This study suggests that M10 in the plate-in-bottle and new oral spirochete medium in the anaerobic chamber are essential in cultivating oral treponemes.