Table 1.

Demographic and full-mouth baseline clinical parameters (mean ± SD) of the study population.

Clinical Parameters		Periodontally Healthy (N = 20)	Good Responders (N = 30)	Refractory Periodontitis (N = 17)
Age (years) *		34 ± 12	48 ± 10	51 ± 11
% Males †		20	60	82
% Smokers † §		0	23	59
% Race	White	75	40	53
	Black	10	43	24
	Hispanic	15	3.5	12
	Asians	0	6.5	6
	Others	0	7	5
Probing depth (mm) *		2.0 ± 0.2	3.7± 1.3	3.9 ± 0.9
Clinical attachment level (mm) * ‡		1.3 ± 0.5	3.2 ± 1.5	4.2 ± 1.2
N of missing teeth *		0.7 ± 1.5	2.1 ± 2.3	3.3 ± 2.8
% of sites with
Bleeding on probing *		11 ± 6.5	56 ± 25	53 ± 28
Supragingival biofilm *		30 ± 22	46 ± 30	65 ± 29
Gingival Redness *		26 ± 18	85 ± 20	88 ± 18
Suppuration		0	0.22 ± 0.7	0.33 ± 0.6

^*p < 0.01, Kruskal-Wallis test;

^†p < 0.01, Chi-square test;

^‡< 0.01, Mann-Whitney test between refractory and good responders;

^§p < 0.01, Chi-square test between refractory and good responders