TABLE 2.

Photoinactivation of P. gingivalis, A. viscosus, and HCPC-1 cells^a

PS	% Survival for organism or cell line
	P. gingivalis	A. viscosus	HCPC-1
Cationic conjugate	1.1 ± 0.9	<0.01	102 ± 2.1
Anionic conjugate	23.9 ± 3.3	24.3 ± 3.4	127 ± 2.9
Neutral conjugate	9.3 ± 2.6	21.2 ± 1.5	108 ± 4.2
Free ce6	39.6 ± 2.3	52.9 ± 5.9	126 ± 2.7
CMA	8.1 ± 1.8	2 ± 0.1	100 ± 2.5
BPD	81.1 ± 9.4	7.6 ± 7.6	8.8 ± 0.7
Mixture (pL and ce6)	8.1 ± 1.8	2 ± 0.1	100 ± 2.5

^aThe percent survival of bacteria was assayed by the colony-forming assay following 1 min of treatment with PS and exposure to 15 J/cm². The viability of HCPC-1 cells was assayed by the microculture tetrazolium assay. Surviving bacteria and epithelial cells were expressed as a percentage of controls receiving PS in the dark out of the incubator. Values for bacteria are the means from three wells, whereas for HCPC-1 cells values are means from six wells, and data are representative of duplicate experiments (± standard errors of the means).