Predictive factors for tooth loss during supportive periodontal therapy in patients with severe periodontitis: a Japanese multicenter study

Table 2 Association between the number of teeth lost due to periodontal disease during SPT and periodontal risk factors at the time of initial examination (Cox proportional hazards model)

Initial examination	Total	Teeth loss due to periodontal disease during SPT			HR	95% CI	p value
Variables	Total	n	Person-years	Rate	HR	95% CI	p value
Sex
Male	34	7	159.3	0.0440	1.00
Female	48	9	243.7	0.0369	0.77	0.29–2.08	0.610
Age
≤ 34	9	3	31.8	0.0945	1.00
35–44	25	4	153.6	0.0260	0.28	0.61–1.26	0.096
45–54	27	7	105.2	0.0666	0.76	0.19–2.97	0.689
55–64	16	1	91.3	0.0110	0.11	0.01–1.10	0.060
≥ 65	5	1	21.2	0.0472	0.51	0.05–5.00	0.562
Diabetes
Non-DM	80	16	398.1	0.0402	1.00
DM	2	0	4.8	0.0000	0.05	0.00–6.27 × 10⁷	0.777
Smoking history
Non-smoker	62	11	301.2	0.0365	1.00
Smoker	20	5	101.8	0.0491	1.41	0.49–4.09	0.522
Number of sites with PD ≥ 6 mm
< 8	6	2	60.6	0.0330	1.00
≥ 8	76	14	342.3	0.0409	1.39	0.30–6.51	0.680
BOP
< 25%	13	5	87.5	0.0571	1.00
≥ 25%	69	11	315.4	0.0349	0.67	0.22–1.98	0.465
Bone loss/age ratio
< 1.0	16	1	67.8	0.0147	1.00
≥ 1.0	66	15	335.1	0.0448	3.19	0.42–24.17	0.262
Number of teeth lost
< 8	74	14	374.3	0.0374	1.00
≥ 8	8	2	28.6	0.0700	2.27	0.48–10.71	0.300

HR hazard ratio, CI confidence interval, DM diabetes mellitus, PD probing depth, BOP bleeding of probing

ISSN: 1472-6831