A Clinical Trial of YH14642 in Patients With Chronic Periodontal Disease

Inclusion Criteria: * Subjects must be 20 years of age or older * Have at least 18 natural teeth * Four or more clinical attachment level(CAL) ≥ 3mm * Four or more periodontal pockets with a probing depth (PD) ≥ 4mm * Have Bleeding on probing * Provide informed consent and willingness to cooperate with the study protocol Exclusion Criteria: * Forbidden History of Panax Notoginseng and Rehmanniae Radix Preparata * Hypersensitivity of Doxycycline * Hypersensitivity of Zea mays L. extract * Critical diseases such as HIV previous three years * Patients with mental retardation and dementia * Systemic diseases such as diabetes and hypertension * Patients who take Anticoagulants or Antiplatelet Agents * Patients who have malignant tumor * Smoker * Continually use for 2weeks of phenytoin, calcium channel blocker, cyclosporin, coumarin, nonsteroidal anti-inflammatory drugs and aspirin use in the previous one month * Patients who need malignant tumor * Patients who received periodontal treatment within the last 6 months * Pregnant or lactating females