Table 2.

Gingival plaque samples positive for bacterial gDNA identified by PCR

Group	Polybacterial infection	Positive gingival plaque samples (n = 10)
		1 weeka	2 weeks	4 weeks	6 weeks	8 weeks
I	Pg/Td/Tf	NC	7/0/6	NC	7/7/7	NC
II	Pg/Td/Tf + collagen	NC	8/0/8	NC	9/7/7	NC
III	Collagen-control	NC	NC	0/0/0	NC	0/0/0
IV	Sham-infected	NC	NC	0/0/0	NC	0/0/0

Total numbers of gingival plaque samples that were collected after infections (1, 2, 4, 6 and 8 weeks) following polymicrobial (P. gingivalis/T. denticola/T. forsythia (Pg/Td/Tf)) infection and were positive as determined by PCR analysis. ^aTime points at which gingival plaque samples were collected. The first value corresponds to the number of mice that tested positive for Pg genomic DNA, the second value to the number of mice that tested positive for Td genomic DNA, and the third value to the number of mice that tested positive for Tf genomic DNA at each time point. NC not collected (to allow bacterial biofilm to adhere to the gingival surface, invade epithelial cells, and multiply), Pg/Td/Tf polybacterial-infected mice, Pg/Td/Tf + collagen polybacterial-infected mice administered collagen II, Collagen-control mice administered collagen II