In recent years, the demand for adult orthodontics has been increasing, with adult orthodontics accounting for about 25% of cases in the United States and an increasing trend in China. However, there is a clear difference between adult orthodontics and pediatric orthodontics, which is related to the physiological, anatomical and psychological characteristics of adults. The skeletal development of adults has been completed, and the potential for jaw development that was available in childhood orthodontics no longer exists in adults, which inevitably affects the development of orthodontic plans, the determination of orthodontic goals and the length of the retention period. Adults are autonomous in their treatment requirements and have their own clear orthodontic goals and aesthetic requirements, so adult orthodontics has a tendency to be more individualized and cannot adopt a more homogeneous orthodontic treatment plan like children’s orthodontics. As adults age, they often have other dental problems, such as dental caries, periodontal disease, TMJ disorders or missing teeth, and may even have some systemic health factors, which will be taken into account in the orthodontic design and treatment process and treated accordingly. In adults, orthodontic teeth should not move too fast because the plasticity of jaws is not as good as in children, and the orthodontic force should be light, so the course of treatment may be relatively longer, and the increased tendency of relapse requires the time to wear retainers to be extended accordingly. Adults may have special requirements for the aesthetics of the aligners due to social activities. Mini brackets, bioceramic brackets, plastic clear brackets and even lingual braces that are invisible from the labial side are the materials and methods available for special requirements.