Dental appliances for treatment of a patient's dentition are provided. In some embodiments, a dental appliance includes a plurality of 3D printed polymer layers, where the plurality of 3D printed polymer layers includes a plurality of sequentially polymerized appliance cross-sections. The dental appliance can include an appliance shell formed from the plurality of sequentially polymerized appliance cross-sections. The appliance shell can include a plurality of tooth receiving cavities formed from the plurality of sequentially polymerized appliance cross-sections, the plurality of tooth receiving cavities arranged to receive a dentition and to exert one or more forces on the dentition, and a plurality of variable thickness regions formed from the plurality of sequentially polymerized appliance cross-sections. The plurality of variable thickness regions can include a corresponding plurality of different appliance thicknesses, and the plurality of variable thickness regions can be arranged to implement one or more treatment outcomes.

Systems and methods for fabricating dental appliances are provided. In some embodiments, a method includes determining an appliance geometry for a dental appliance, where the appliance geometry includes a first region representing a first shell portion having a first set of cavities configured to receive one or more first teeth at a first side of a dental arch of a patient, a second region representing a second shell portion having a second set of cavities configured to receive one or more second teeth at a second side of the dental arch, and a third region representing an integrally formed arch expander configured to exert forces to increase a width of the dental arch. The method can also include generating instructions for fabricating the dental appliance having the appliance geometry via an additive manufacturing process, and using the instructions to instruct a fabrication system to fabricate the dental appliance.

Dental appliances and associated methods are provided herein. In some embodiments, a dental appliance includes an appliance shell formed from a plurality of 3D printed polymer layers. The appliance shell can include a plurality of tooth receiving cavities arranged to receive a dentition and to exert one or more forces on the dentition, and a plurality of variable thickness regions integrally formed with the appliance shell as a single monolithic component. The plurality of variable thickness regions can include an upper thickened region at a first side of a tooth receiving cavity and a lower thickened region at a second side of the tooth receiving cavity opposite the first side. The upper and lower thickened regions can be configured to control movement of a tooth received within the tooth receiving cavity.