# US 11,896,457 B2 · Systems and methods for fabrication of orthodontic aligners > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,896,457 B2 - Document ID: US11896457B2 - Status: Granted - Kind: B2 - Application number: 18/115,989 - Filed: 2023-03-01 - Published: 2023-06-29 - Granted: 2024-02-13 - Earliest claimed: 2010-04-30 - Assignees: Align Technology, Inc. - Applicants: Align Technology, Inc. - Inventors: Eric Kuo; Artem Borovinskih; Shiva Sambu - Web page: https://patentgrep.com/patent/US11896457B2 ## CPC - A61C 7/002: {Orthodontic computer assisted systems} - A61C 7/08: Mouthpiece-type retainers {or positioners, e.g. for both the lower and upper arch (arch-shaped medicament applicators for teeth or gums A61C19/063; mouthguards for protecting the teeth of sportsmen A63B71/085)} - B33Y 50/02: for controlling or regulating additive manufacturing processes - G06F 30/20: Design optimisation, verification or simulation (optimisation, verification or simulation of circuit designs G06F30/30) - A61C 9/0046: {Data acquisition means or methods} - A61C: DENTISTRY; APPARATUS OR METHODS FOR ORAL OR DENTAL HYGIENE (non-driven toothbrushes A46B; {tongue scrapers A61B17/24;} preparations for dentistry A61K6/00; preparations for cleaning the teeth or mouth A61K8/00, A61Q11/00) - B33Y: ADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) ## Abstract Orthodontic positioning devices, and related methods and systems, are disclosed for use with one or more orthodontic elastic members. The disclosed methods may comprise determining the geometries for a pair of orthodontic aligners for use as part of an orthodontic treatment plan. The geometries for the pair of orthodontic aligners may include an upper aligner with a first marking and a lower aligner with a second marking. The first marking may correspond to a position of a first hook, and the second marking may correspond to a position of a second hook. The first hook and the second hook may be configured to engage with an orthodontic elastic member so as to react a force to, for example, generate orthodontic forces on the patient's teeth. ## Claims ### Claim 1 A method of planning an orthodontic treatment, the method comprising: receiving an initial dentition model of a patient's teeth in an initial arrangement; determining a target arrangement for the patient's teeth; generating an orthodontic treatment plan, wherein the orthodontic treatment plan comprises a plurality of incremental arrangements to sequentially reposition the patient's teeth from the initial arrangement towards the target arrangement; determining, for at least one of the plurality of incremental arrangements, a geometry corresponding to a pair of orthodontic aligners, wherein the geometries for the pair of orthodontic aligners comprises: a first plurality of teeth-receiving cavities corresponding to an upper aligner, wherein the first plurality of teeth-receiving cavities are configured to receive at least a portion of the patient's upper dentition; a first marking disposed on the first plurality of teeth-receiving cavities, wherein the first marking corresponds to a position of a first hook for receiving a first end of an elastic band; a second plurality of teeth-receiving cavities corresponding to a lower aligner, wherein the second plurality of teeth-receiving cavities are configured to receive at least a portion of the patient's lower dentition; a second marking disposed on the second plurality of teeth-receiving cavities, wherein the second marking corresponds to a position of a second hook for receiving a second end of the elastic band; and fabricating the pair of orthodontic aligners based on the geometries determined, wherein fabricating the pair of orthodontic aligners comprises: forming the first plurality of teeth-receiving cavities; forming the first marking on the first plurality of teeth-receiving cavities; forming the second plurality of teeth-receiving cavities; and forming the second marking on the second plurality of teeth-receiving cavities; wherein the first hook extends in a gingival direction relative to a gingival edge of the geometry of the upper aligner. ### Claim 2 (depends on 1) The method of planning an orthodontic treatment of claim 1, further comprising forming the first hook by cutting along the first marking on the first plurality of teeth-receiving cavities. ### Claim 3 (depends on 1) The method of planning an orthodontic treatment of claim 1, further comprising forming the first hook by cutting the first plurality of teeth-receiving cavities based on the first marking. ### Claim 4 (depends on 1) The method of planning an orthodontic treatment of claim 1, further comprising forming the first hook by manually cutting the first plurality of teeth-receiving cavities. ### Claim 5 (depends on 1) The method of planning an orthodontic treatment of claim 1, further comprising forming the first hook by laser cutting the first plurality of teeth-receiving cavities. ### Claim 6 (depends on 1) The method of planning an orthodontic treatment of claim 1, wherein the first plurality of teeth-receiving cavities and the first marking are formed together in a thermoforming process. ### Claim 7 (depends on 1) The method of planning an orthodontic treatment of claim 1, wherein the first marking comprises an indentation along the first plurality teeth-receiving cavities. ### Claim 8 (depends on 1) The method of planning an orthodontic treatment of claim 1, wherein the first marking comprises a protrusion along the first plurality teeth-receiving cavities. ### Claim 9 (depends on 1) The method of planning an orthodontic treatment of claim 1, further comprising forming the first hook by cutting the first plurality of teeth-receiving cavities and forming the second hook by cutting the second plurality of teeth-receiving cavities; wherein cutting the first plurality of teeth-receiving cavities comprises removing material along the first marking to form a first U-shaped recess as the first hook; and wherein cutting the second plurality of teeth-receiving cavities comprises removing material along the second marking to form a second U-shaped recess as the second hook. ### Claim 10 (depends on 9) The method of providing orthodontic treatment of claim 9, wherein the first U-shaped recess and second U-shaped recess are oriented in opposing directions. ### Claim 11 (depends on 1) The method of providing orthodontic treatment of claim 1, wherein the first hook is pointed mesially and the second hook is pointed distally. ### Claim 12 (depends on 1) The method of providing orthodontic treatment of claim 1, wherein the first hook and the second hook are disposed at positions corresponding to a non-occluding pair of the patient's teeth. ### Claim 13 (depends on 1) The method of planning an orthodontic treatment of claim 1, further comprising fabricating a first positive mold corresponding to an arrangement of the patient's upper dentition. ### Claim 14 (depends on 1) The method of planning an orthodontic treatment of claim 1, wherein forming the first plurality of teeth-receiving comprises thermoforming a sheet of polymeric material over the first positive mold. ### Claim 15 (depends on 1) The method of planning an orthodontic treatment of claim 1, wherein the first marking comprises a reference feature to guide subsequent removal of material from the upper aligner to form the first hook. ### Claim 16 A non-transitory computing device readable medium storing instructions executable by a processor to cause a computing device to perform a method, the method comprising: receiving an initial dentition model of a patient's teeth in an initial arrangement; determining a target arrangement for the patient's teeth; generating an orthodontic treatment plan, wherein the orthodontic treatment plan comprises a plurality of incremental arrangements to sequentially reposition the patient's teeth from the initial arrangement towards the target arrangement; determining, for at least one of the plurality of incremental arrangements, a geometry corresponding to a pair of orthodontic aligners, wherein the geometries for the pair of orthodontic aligners comprises: a first plurality of teeth-receiving cavities corresponding to an upper aligner, wherein the first plurality of teeth-receiving cavities are configured to receive at least a portion of the patient's upper dentition; a first marking disposed on the first plurality of teeth-receiving cavities, wherein the first marking corresponds to a position of a first hook for receiving a first end of an elastic band; a second plurality of teeth-receiving cavities corresponding to a lower aligner, wherein the second plurality of teeth-receiving cavities are configured to receive at least a portion of the patient's lower dentition; a second marking disposed on the second plurality of teeth-receiving cavities, wherein the second marking corresponds to a position of a second hook for receiving a second end of the elastic band; and fabricating the pair of orthodontic aligners based on the geometries determined, wherein fabricating the pair of orthodontic aligners comprises: forming the first plurality of teeth-receiving cavities; forming the first marking on the first plurality of teeth-receiving cavities; forming the second plurality of teeth-receiving cavities; and forming the second marking on the second plurality of teeth-receiving cavities; wherein the first hook extends in a gingival direction relative to a gingival edge of the geometry of the upper aligner. ### Claim 17 (depends on 16) The non-transitory computing device readable medium of claim 16, wherein the instructions further comprise forming the first hook by cutting along the first marking on the first plurality of teeth-receiving cavities. ### Claim 18 (depends on 16) The non-transitory computing device readable medium of claim 16, wherein the instructions further comprise forming the first hook by cutting the first plurality of teeth-receiving cavities based on the first marking. ### Claim 19 (depends on 16) The non-transitory computing device readable medium of claim 16, wherein the instructions further comprise forming the first hook by laser cutting the first plurality of teeth-receiving cavities. ### Claim 20 (depends on 16) The non-transitory computing device readable medium of claim 16, wherein the first plurality of teeth-receiving cavities and the first marking are formed together in a thermoforming process. ### Claim 21 (depends on 16) The non-transitory computing device readable medium of claim 16, wherein the first marking comprises an indentation along the first plurality teeth-receiving cavities. ### Claim 22 (depends on 16) The non-transitory computing device readable medium of claim 16, wherein the first marking comprises a protrusion along the first plurality teeth-receiving cavities. ### Claim 23 (depends on 16) The non-transitory computing device readable medium of claim 16, wherein the instructions further comprise: forming the first hook by cutting the first plurality of teeth-receiving cavities and forming the second hook by cutting the second plurality of teeth-receiving cavities; wherein cutting the first plurality of teeth-receiving cavities comprises removing material along the first marking to form a first U-shaped recess as the first hook; and wherein cutting the second plurality of teeth-receiving cavities comprises removing material along the second marking to form a second U-shaped recess as the second hook. ### Claim 24 (depends on 23) The non-transitory computing device readable medium of claim 23, wherein the first U-shaped recess and second U-shaped recess are oriented in opposing directions. ### Claim 25 (depends on 16) The non-transitory computing device readable medium of claim 16, wherein the first hook is pointed mesially and the second hook is pointed distally. ### Claim 26 (depends on 16) The non-transitory computing device readable medium of claim 16, wherein the first hook and the second hook are positioned on a non-occluding pair of the patient's teeth. ### Claim 27 (depends on 16) The non-transitory computing device readable medium of claim 16, wherein the geometries are determined using a three-dimensional treating planning and design tool. ### Claim 28 (depends on 16) The method of planning an orthodontic treatment of claim 16, wherein the first marking comprises a reference feature to guide subsequent removal of material from the upper aligner to form the first hook. ### Claim 29 A method of planning an orthodontic treatment, the method comprising: receiving an initial dentition model of a patient's teeth in an initial arrangement; determining a target arrangement for the patient's teeth; generating an orthodontic treatment plan, wherein the orthodontic treatment plan comprises a plurality of incremental arrangements to sequentially reposition the patient's teeth from the initial arrangement towards the target arrangement; determining, for at least one of the plurality of incremental arrangements, a geometry corresponding to an orthodontic aligner, wherein the geometry comprises: a plurality of teeth-receiving cavities configured to receive at least a portion of the patient's upper or lower dentition; and a marking disposed on the plurality of teeth-receiving cavities, wherein the marking corresponds to a position of a hook for receiving an end of an elastic band; fabricating the orthodontic aligner based on the geometry determined, wherein fabricating the orthodontic aligner comprises: forming the plurality of teeth-receiving cavities; forming the marking on the first plurality of teeth-receiving cavities; and forming the hook by cutting the plurality of teeth-receiving cavities based on the marking; wherein cutting the plurality of teeth-receiving cavities comprises manual cutting; wherein the hook extends in a gingival direction relative to a gingival edge of the geometry of the upper aligner. ### Claim 30 (depends on 29) The method of planning an orthodontic treatment of claim 29, further comprising forming the hook by cutting the plurality of teeth-receiving cavities based on the marking. ### Claim 31 (depends on 29) The method of planning an orthodontic treatment of claim 29, further comprising forming the hook by manually cutting the plurality of teeth-receiving cavities. ### Claim 32 (depends on 29) The method of planning an orthodontic treatment of claim 29, wherein the plurality of teeth-receiving cavities and the marking are formed together in a thermoforming process. ### Claim 33 (depends on 27) The method of planning an orthodontic treatment of claim 27, wherein the marking comprises a reference feature to guide removal of material from the orthodontic aligner to form the hook.