The term "prehypertension" indicates those with BPs ranging from 120 to 139 mm Hg systolic and/or 80 to 89 mm Hg diastolic blood pressure. Accumulating evidence suggests that subjects with prehypertension is associated with higher incidence of atherosclerotic vascular disease. However, until now there are no available data to investigate the influence of periodontitis on prehypertension and whether periodontal intervention may reduce the BP rise in subjects with prehypertension and improve the vascular function. We hypothesized that periodontitis leads to elevation in BP and periodontal therapy improves vascular function in subjects with prehypertension. To address these assumptions, The present study is designed to study the effect of periodontal intervention on blood pressure and vascular function and inflammatory biomarkers among Chinese prehypertensive adults with moderate to severe periodontal disease, and determine whether intensive periodontal therapy improves these measures over a 6-month follow-up period.