MMP9 and periodontitis: In comparison to healthy controls, MMP-9 concentrations in serum and saliva were statistically elevated in patients with CVD [serum: 51.3 (38.2–64.4) ng/mL; saliva 256.4 (217.4–549.5) ng/mL, p < 0.01] and in patients with periodontitis + CVD [serum: 53.8 (38.5–64.7) ng/mL; saliva 265.6 (165.5–586.7) ng/mL, p < 0.001].