Table 2 shows a comparison of the baseline cytokine levels between the NP and ET groups. No statistical differences existed in the baseline cytokine levels between the 2 groups.  Table 3 shows the correlations between baseline salivary proinflammatory cytokines in patients with periodontitis. Baseline salivary IL-1β was significantly correlated with baseline IL-1α, IL-6, IL-8, and TNF-β; the correlation coefficients were 0.46, 0.72, 0.60, and −0.46, respectively. The gene discussed is CXCL8; the disease is periodontitis.