Background  Periodontitis is a kind of infectious disease which affectes supporting tissues of teeth, and causes them to swell and pain during acute age, and the course of chronic periodontitis is so long and developing that teeth may loss. According to the research of WHO in 35 countries, the disease incidence is 40%～75%. It can destroy beautiful outlook, pronounciation, masticatory and digestive function , moreover many researches shew that periodontitis is concerned with individual systemic health nowadays, and it may be a risk factor of some systemic diseases. The formation of subgingival plaque results in periodontitis, and bacteriums are an essential phthopoiesis factor, so antibacterial drug therapy is a significant method. Systemic antibacterials can inhibit latent pathogenic bacteria invading periodontal tissues or other parts in buccal cavity(such as amygdale , dorsum linguae). While, even if given systemic flushing dose antibacterials, drugs still concentrated in blood serum. Patients were requested to administer repeatedly, which will cause dysbacteria, increasing adverse reaction, weak compliance and so on . Local antibacterials therapy can improve local effective drug concentration, and can achieve 10～100 times than systemic antibacterials. Meanwhile it can decrease adverse reaction and chemical sproof. Local slow-release praeparatum overcome the shortcomings of systemic or local administration. It can reduce the dosage of medicine, prolong the drug action, avoid the phenomenon of the peak valley of concentration in blood and decrease the frequency of administration. Doser of subgingiva is divided into fiber, powder, drug stick, pasta, gel or ointment.  Objective  We will design the tooting of suppository refer to different teeth or sizes. The suppository will be prepared with ornidazole and pefloxacinmesylate as main ingredient,