Accumulated evidence has strongly suggested that the long-term effects of periodontal diseases can be linked to more serious systemic conditions such as cardiovascular diseases, diabetes, and complications of pregnancy. Especially, a prevalence of coronary heart disease was found to be significantly increased in patients with periodontitis after adjusting for risk factors such as smoking, diabetes, alcohol intake, obesity, and blood pressure. Furthermore, various studies have shown that Porphyromonas gingivalis, a major periodontal pathogen, is able to exacerbate atherosclerosis following oral-hematogenous spread due to the bacteremia. By P. gingivalis, endothelial cells activate and upregulate various adhesion molecules, thus increasing the likelihood of macrophage diapedesis and subsequent conversion to foam cells thus furthering athroma progression. These findings likely indicate the tight relationship between periodontitis/periodontal pathogens and cardiovascular diseases.