A Nested Case-Control Study of the Relationship between Salivary Inflammatory Mediators, Periodontal Parameters, and Preterm Birth in a Chinese Population

Table 2

Periodontal indexes and PGE2, IL-1β, IL-6, TNF-α, and 8-OHdG salivary levels in PTB and FTB in group A.

Variables	FTB control ()	Nested control ()	PTB ()	value (FTB control)	value (nested control)
PD (mm)				0.12	0.054
(%)	5.36; (1.04 to 15.78)	5.36; (0.60 to 19.64)	3.93; (0 to 8.19)	0.21	0.35
BI	2.00; (1.43 to 2.61)	2.03; (1.29 to 2.61)	1.90; (1.06 to 2.46)	0.16	0.29
TNF-α (pg/ml)				0.27	0.68
IL-1β (pg/ml)				0.49	0.86
PGE2 (pg/ml)				0.21	0.30
IL-6 (pg/ml)				0.38	0.45
8-OHdG (pg/ml)				0.32	0.50

. BI: bleeding index; FTB: full term birth; PTB: preterm birth; IL-1β: interleukin-1β; IL-6: interleukin-6; 8-OHdG: 8-hydroxy-deoxyguanosine; PD: probing depth; PGE2: prostaglandin E2; TNF-α: tumor necrosis factor-α.