A method for generating tooth arrangements is provided. The method includes: receiving a digital model representing an initial tooth arrangement； determining K orthodontic treatment step parameters, wherein the orthodontic treatment step parameters represent the number of orthodontic treatment steps for moving the initial tooth arrangement to an expected tooth arrangement, and K is an integer greater than or equal to 1； for each orthodontic treatment step parameter, generating a group of digital models representing a tooth arrangement set corresponding to the orthodontic treatment step parameter, thereby obtaining K groups of digital models； and selecting one group from the K groups of digital models that represents a best tooth arrangement set. A method for manufacturing a dental appliance based on the obtained tooth arrangement and the dental appliance manufactured according to the method are also provided.
