The predominant cultivable dental plaque flora of beagle dogs with gingivitis.

The predominant dental plaque flora of 15 female beagle dogs (1,3 and 6 year old) with naturally developed gingivitis was studied using a continuous anaerobic culturing technique. Supraand sul^ingival plaque samples from the buccal aspect of the upper third premolar were cultured on various growth media and the organisms were partially characterized. The flora in all dogs was composed mostly of anaerobic Gram negative organisms. B. asaccharoiyticus (B. melaninogenicus ss. asaccharoiyticus) was found in both types of plaques in all animals and decompKJsed hydrogen peroxide suggesting catalase activity. F. nucleatum was found in higher proportions in the subgingival plaque as compared to B. asaccharoiyticus and actinomycetes. Spirochetes were found in 10 of 15 supraand in 1 of 15 subgingival specimens. S. mutans, S. mitior, S. salivarius, Veillonella, Selenomonas or vibrios could not be detected in any of the plaque samples. A combined data analysis showed, that the total viable CFU and the proportions of Gram positive organisms were significantly higher in the suprathan the subgingival plaque. Although the proportions of Gram negative bacteria were higher in subgingival plaque, the differences between the two tyi>es of plaques excluding F. nucleatum were not significant.