Growth and Identification of Bacteria in N-Halamine Dental Unit Waterline Tubing Using an Ultrapure Water Source

Table 2

Logarithmic mean CFU/mL of bacteria dislodged from inside surfaces of test and control tubing.

Week	Treatment	N	Log mean	Log Std Dev	Geometric mean	t-value	𝑃 value
3	Test	3	0.784	0.719	5.1	3.48	0.025
	Control	3	2.321	0.263	208.3	Test < control
6	Test	3	1.397	0.338	23.9	1.73	0.159
	Control	3	2.310	0.851	203.4
9	Test	3	0.627	0.737	3.2	2.78	0.05
	Control	3	2.007	0.443	100.7	Test < control
12	Test	3	1.900	0.747	78.4	0.37	0.729
	Control	3	2.079	0.374	119.0
18	Test	3	1.838	0.923	67.8	0.09	0.936
	Control	3	1.762	1.229	56.8
24	Test	3	2.580	0.296	379.4	3.69	0.021
	Control	3	3.280	0.144	1905.6	Test < control
All Weeks	Test	6	1.521	0.738	32.2	2.09	0.063
	Control	6	2.293	0.526	195.5