. 2020 Nov 16;10:571515. doi: 10.3389/fcimb.2020.571515

Table 1.

Characteristics of healthy subjects and periodontitis patients (n = 692).

Characteristics	Healthy (n = 144)	Chronic periodontitis			P-value
Characteristics	Healthy (n = 144)	Slight(n = 95)	Moderate(n = 245)	Severe(n = 208)
Sex
Male	70 (48.6%)	42 (44.2%)	126 (51.4%)	123 (59.1%)	0.065^a
Female	74 (51.4%)	53 (55.8%)	119 (48.6%)	85 (40.9%)	0.065^a
Age (yr)
20-29	79 (54.9%)	6 (6.3%)	3 (1.2%)	0 (0.0%)	<0.001^a
30-39	42 (29.2%)	20 (21.1%)	18 (7.3%)	11 (5.3%)
40-49	3 (2.1%)	20 (21.1%)	45 (18.4%)	48 (23.1%)
50-59	10 (6.9%)	26 (27.4%)	85 (34.7%)	97 (46.6%)
≥60	10 (6.9%)	23 (24.2%)	94 (38.4%)	52 (25.0%)
Clinical attachment level (mm)
Mean ± SD	2.46 ± 0.29	2.82 ± 0.40	3.49 ± 0.67	4.47 ± 1.18	<0.001^b
Median (IQR)	2.47 (2.24-2.66)	2.80 (2.53-3.03)	3.40 (3.05-3.79)	4.26 (3.71-5.09)	<0.001^b
Pocket depth (mm)
Mean ± SD	2.43 ± 0.29	2.67 ± 0.36	3.16 ± 0.60	3.90 ± 0.89	<0.001^b
Median (IQR)	2.44 (2.23-2.64)	2.68 (2.44-2.88)	3.13 (2.82-3.47)	3.85 (3.29-4.32)	<0.001^b
Plaque index
Mean ± SD	17.00 ± 14.68	32.36 ± 21.33	46.12 ± 25.47	52.78 ± 25.76	<0.001^b
Median (IQR)	13.84 (7.14-22.24)	30.95 (15.83-48.28)	46.88 (24.50-61.61)	50.00 (31.96-71.76)	<0.001^b
Gingival index
Mean ± SD	0.08 ± 0.16	0.39 ± 0.40	0.70 ± 0.49	1.01 ± 0.55	<0.001^b
Median (IQR)	0.03 (0.00-0.10)	0.27 (0.14-0.51)	0.63 (0.29-1.05)	0.99 (0.50-1.50)	<0.001^b
Smoking history
Never	120 (83.3%)	69 (72.6%)	144 (58.8%)	97 (46.6%)	<0.001^a
Former	19 (13.2%)	17 (17.9%)	52 (21.2%)	51 (24.5%)
Daily	5 (3.5%)	9 (9.5%)	49 (20.0%)	60 (28.8%)
Additional oral care (dental floss, mouthwash)
Yes	113 (78.5%)	69 (72.6%)	147 (60.0%)	113 (54.3%)	<0.001^a
No	31 (21.5%)	26 (27.4%)	98 (40.0%)	95 (45.7%)	<0.001^a
Toothbrushing frequency per day
≥3 times	114 (79.2%)	53 (55.8%)	116 (47.3%)	95 (45.7%)	<0.001^a
≤2 times	30 (20.8%)	42 (44.2%)	129 (52.7%)	113 (54.3%)

^aChi-squared test, ^bKruskal-Wallis One Way Analysis of Variance on Ranks.