Gram negative species associated with active destructive periodontal lesions

Apical subgingival plaque samples were taken from 19 subjects exhibiting active destructive periodontal disease. The predominant cultivable Gram negative species from 50 active sites were compared to 69 inactive sites of comparable pocket depth and attachment level loss. Active disease sites were chosen which showed a significant loss of attachment within a two-month interval. Proportions of Gram negative rods were higher in active periodontal disease sites than in inactive sites. Species which were found to be significantly elevated only in active sites were Bacteroides intermedius, "fusiform" Bacteroides, Actinobacillus actinomycetemcomitans and Wolinella recta. Fusobacterium nucleatum, Capnocytophaga gingivalis and Eikenella corrodens were found in significantly increased proportions in active sites of some subjects and inactive sites of others.