Medicinal mouthwashes are useful as an adjunctive treatment for patients with periodontitis. Mouthwash is categorized into health care and medicinal. Mouthwash for health care is mainly for cleaning teeth and mouth, and does not have anti-inflammatory effect. Medicinal mouthwash contains antibiotics or other medications that can effectively inhibit bacterial growth and improve oral inflammation. Periodontitis is due to plaque and other plaque invasion of periodontal tissue caused by the use of medicinal mouthwash can help remove microorganisms in the oral cavity, so as to avoid the bacteria continue to grow and multiply in the dental face and periodontal pockets, reduce the inflammation of the gums, anti-inflammatory and antibacterial play a role in the treatment. However, the long-term use of medicinal mouthwash can also produce oral flora imbalance, inhibit salivary secretion, produce resistance and other hazards, should be used under the guidance of a doctor. The correct treatment of periodontitis is to visit a specialized hospital for treatment, firstly through dental scaling to remove periodontal plaque, calculus, and remove irritating factors. Secondly, the use of metronidazole, ornidazole and other drugs under the guidance of the doctor, to avoid anaerobic bacteria continue to infect. If the above treatment still fails to achieve a good therapeutic effect, it is necessary to consider flap surgery, bone grafting and other surgical treatments.