A removable dental appliance (300, 400, 500, 600, 700, 800, 900, 1000, 1100) comprising: an appliance body (302, 402, 502, 602, 702, 802, 902, 1002, 1102) configured to at least partially surround a plurality of teeth (301, 303, 305, 401, 403, 405, 701, 703, 705, 801, 803, 805, 901, 903, 905) of a dental arch of a patient, the appliance body comprising: a unitary material defining a shell (310, 410, 510, 710, 810, 910) shaped to receive at least one tooth (301, 401, 501, 601, 701, 801, 901) of the patient; a spring member (304, 404, 504, 604, 704, 804, 904, 1004, 1104) integrally formed with the shell; and a positioning member (322, 422, 522, 622, 722, 822, 922, 1022, 1122) integrally formed with the shell, wherein the positioning member includes a deflection of the shell away from an occlusal surface of the dental arch, creating a cavity between the shell and occlusal surfaces of the teeth when the appliance is seated on the dental arch, wherein the spring member is configured to receive an attachment (306, 406, 506, 706, 806, 906, 1006) affixed to the at least one tooth, wherein the spring member is configured to apply a spring force (308, 408, 508, 708, 808, 908) to the attachment to cause movement of the at least one tooth toward a desired position when the removable dental appliance is worn by the patient, and wherein the positioning member is configured to deform the appliance body to facilitate engagement of the spring member with the attachment in response to a positioning force (324, 424, 724, 924, 1024, 1124) being applied to the positioning member, and wherein the appliance body comprises at least one flexural region (326, 426) configured to facilitate said deformation of the appliance body when the positioning force is applied to the positioning member, wherein the at least one flexural region comprises a fold in the appliance body. a unitary material defining a shell (310, 410, 510, 710, 810, 910) shaped to receive at least one tooth (301, 401, 501, 601, 701, 801, 901) of the patient; a spring member (304, 404, 504, 604, 704, 804, 904, 1004, 1104) integrally formed with the shell; and a positioning member (322, 422, 522, 622, 722, 822, 922, 1022, 1122) integrally formed with the shell, wherein the positioning member includes a deflection of the shell away from an occlusal surface of the dental arch, creating a cavity between the shell and occlusal surfaces of the teeth when the appliance is seated on the dental arch, wherein the spring member is configured to receive an attachment (306, 406, 506, 706, 806, 906, 1006) affixed to the at least one tooth, wherein the spring member is configured to apply a spring force (308, 408, 508, 708, 808, 908) to the attachment to cause movement of the at least one tooth toward a desired position when the removable dental appliance is worn by the patient, and wherein the positioning member is configured to deform the appliance body to facilitate engagement of the spring member with the attachment in response to a positioning force (324, 424, 724, 924, 1024, 1124) being applied to the positioning member, and wherein the appliance body comprises at least one flexural region (326, 426) configured to facilitate said deformation of the appliance body when the positioning force is applied to the positioning member, wherein the at least one flexural region comprises a fold in the appliance body.