Table 1.

Profile of the healthy control group and periodontitis patients.

	Number in figure	IgG level (FDC381)	IgG level (SU63)	Number of present teeth	Bone loss (Schei value)
Healthy	H1	−0.383	0.155	28	N.D.
	H2	−0.322	−0.239	28	N.D.
	H3	−0.557	−1.367	28	N.D.
	H4	−0.152	0.425	28	N.D.
	H5	−0.536	−1.307	28	N.D.
	H6	−0.562	−1.201	28	N.D.
	H7 (a1)	−0.634	−1.446	28	N.D.
	H8 (a2)	−0.647	−1.365	28	N.D.
	H9	−0.635	−1.321	28	N.D.
	H10 (a3)	−0.666	−1.445	28	N.D.
Periodontitis	b1	5.450	10.180	N.A.	N.A.
	b2	7.550	5.070	N.A.	N.A.
	b3	13.320	5.850	N.A.	N.A.
	c1	1.800	0.060	N.A.	N.A.
	c2	15.110	9.080	N.A.	N.A.
	c3	13.360	5.520	N.A.	N.A.
	P1	1.093	0.054	17	77.06
	P2	2.365	1.558	17	55.59
	P3	0.000	−0.813	10	55.50
	P4	1.211	−0.504	27	53.33
	P5	1.912	0.269	28	51.79
	P6	1.052	−0.202	24	47.50
	P7	2.415	0.755	22	44.77
	P8	37.587	11.373	18	43.06
	P9	0.040	−0.179	18	42.22
	P10	3.901	3.246	25	38.80
	P11	0.647	1.137	29	11.03
	P12	1.207	0.648	30	15.83
	P13	2.474	0.603	29	16.90
	P14	0.000	−0.521	27	17.04
	P15	8.073	1.324	25	19.80
	P16	2.270	0.814	16	20.00
	P17	−0.147	0.510	28	20.54
	P18	18.572	4.248	30	20.67
	P19	0.095	−0.378	28	20.89
	P20	1.657	−0.454	17	23.53

Serum samples were obtained from 10 healthy subjects without bone loss (five male and five females; mean ± standard deviation age, 34 ± 5 years) and 26 patients with periodontitis (11 males and 15 females; mean ± standard deviation age, 52 ± 12 years). Serum IgG levels against P. gingivalis FDC381 and SU63 were measured by enzyme linked immunosorbent assay. The extent of bone loss was measured by the methods of Schei. Schei indices were classified as: <25% represents mild bone loss and >35% represents severe bone loss.

IgG levels of healthy subjects were usually lower than 1. In addition, healthy subjects had 28 teeth and no bone loss was detected (shown as N.D.). Meanwhile, numbers of teeth and bone loss of periodontitis patients used for affinity column (b1-b3 and c1-c3) were not available (shown as N.A.).