A multilayer sheet comprising first, second, and third layers is provided. The first layer consists of a co-polyester having an elongation at break of greater than 70%. The second layer consists of a thermoplastic polyurethane elastomer having an elongation at break of greater than 200% and a hardness of about 60 A to about 85 D. The first layer has a hardness greater than the hardness of the second layer. A mold is provided and the multilayer sheet is thermoformed over the mold to form a plurality of tooth-receiving cavities configured to receive and position a patient's teeth from a first arrangement toward a second arrangement. Excess material is trimmed from the thermoformed multilayer sheet to form the multilayer dental aligner.