Methods for direct fabrication of appliances for palate expansion

A method for fabricating an orthodontic appliance, the method comprising:

• receiving, by a processor, scan data of an upper arch and a palate of a patient, wherein the scan data comprises a 3D model;
• receiving, by the processor, a selected rate of palatal expansion for the patient;
• determining, by the processor, an amount of force to expand the palate based on the scan data and the selected rate of palatal expansion;
• generating, by the processor, a 3D model of an orthodontic appliance configured to expand the palate of the patient, wherein the orthodontic appliance includes first and second teeth engaging regions configure to receive and deliver a force to teeth of the patient and a transpalatal region extending between the first and second teeth engaging regions, and wherein the generating comprises:
• determining, by the processor, a structure of the first and second teeth engaging regions;
• and
• determining, by the processor, a structure of the transpalatal region to provide the force based at least partially on a varying rigidity in the transpalatal region that comprises a first region of the transpalatal region having a different rigidity than a second region of the transpalatal region, wherein the transpalatal region comprises a top surface and a bottom surface, and wherein a vertical height of the transpalatal region is determined to form a gap that inhibits contact of the top surface with a top of the palate of the patient when the orthodontic appliance is worn by the patient, and wherein a portion of the transpalatal region is shaped to engage and deliver a force directly to lateral sides of the palate of the patient, and wherein the amount of force to expand the palate comprises a first amount of force applied directly to the lateral sides of the palate and a second amount of force applied to the teeth of the patient;
• generating, by the processor, direct fabrication instructions based on the 3D model to manufacture the orthodontic appliance with the first and second teeth engaging regions and the transpalatal region;
• receiving, by a fabrication machine, the direct fabrication instructions;
• and
• directly manufacturing, by the fabrication machine, the orthodontic appliance according to the direct fabrication instructions.