CCL2 and gingivitis: Likewise, we observed enhanced circulating levels of the inflammatory mediators for IL-6 (Median difference 12.52 ng/l, 95% CI 1.25 to 43.85; P = 0.0002) and MCP-1 (Median difference 9.10 ng/l, 95% CI −3.70 to 28.65; P = 0.124) (Fig. 4B and C) between baseline and gingivitis, which both returned to baseline levels at the follow-up appointment (Median difference for IL-6 −12.51 ng/l, 95% CI −44.65 to −1.36; P = 0.001 and median difference for MCP-1 −12.10 ng/l, 95% CI −27.00 to 0.50; P = 0.057).