Orthodontic treatment is available for patients with periodontitis. In China, adults with periodontitis have a high prevalence and complex etiology, and usually require comprehensive periodontal health maintenance and a combination of treatment measures. In general, there are 2 kinds of orthodontic treatment for patients with periodontitis: one is to have misalignment and periodontitis at the same time, requiring orthodontic treatment for misalignment; the other is to have misalignment due to periodontitis and orthodontic treatment for misalignment in order to treat periodontitis, such as periodontitis causing gaps and protrusion of teeth, which affects facial aesthetics and occlusal function, often need to cooperate with orthodontic It is often necessary to cooperate with orthodontic treatment to fix the teeth, and to carry out controlled tooth movement, adjust the occlusal relationship, and restore the aesthetic appearance of the teeth. It is clinically believed that malocclusion is harmful to periodontal health and timely orthodontic treatment can not only correct malocclusion but also have a preventive effect on periodontal disease. In addition, orthodontic treatment of malocclusion due to periodontal disease will effectively improve the periodontal environment in the oral cavity. Therefore, orthodontic treatment has been considered as a treatment tool in periodontology.