Three-slot appliance is an appliance used in orthodontics, which is mainly composed of three slots. These grooves can work together to improve the efficiency of orthodontics and solve some problems in traditional orthodontics. Specifically, the design concept of three-slot appliance is to combine the advantages of traditional straight wire appliance and Begg appliance, and at the same time make up for their shortcomings. The straight wire arch technique can make the teeth move as a whole, but not obliquely; Begg orthodontics can make teeth move quickly, but it is more complicated to control teeth accurately in the later stage. Three-slot appliance combines the advantages of both and can obviously shorten the course of treatment. In practical application, the main groove of the three-groove corrector adopts a design similar to the sharp-edged groove, which can meet the requirements of the sharp-edged process. In addition, an auxiliary groove is added at the gingival end and the incisor end, and the three grooves work together to improve the efficiency and solve some defects in Begg technology and straight wire arch technology. Generally speaking, the three-slot appliance is an innovative orthodontic equipment, which combines the advantages of various orthodontic techniques, improves the efficiency of orthodontics and reduces the treatment time, and is a good choice for people who need orthodontics.