Protruding aligner hooks

An orthodontic aligner, the orthodontic aligner comprising:

• an upper appliance, the upper appliance comprising:
• a first plurality of teeth-receiving cavities configured to receive at least a portion of the patient's upper dentition,
• a first protrusion extending buccally from the first plurality of teeth-receiving cavities, wherein the first plurality of teeth-receiving cavities and the first protrusion are formed together;
• and
• a first hook formed on the first protrusion;
• a lower appliance, the lower appliance comprising:
• a second plurality of teeth-receiving cavities configured to receive at least a portion of the patient's lower dentition,
• a second protrusion extending buccally from the second plurality of teeth-receiving cavities, wherein the first plurality of teeth-receiving cavities and the first protrusion are formed together, and
• a second hook formed on the second protrusion;
• wherein the first hook is configured to receive a first end of an elastic band, and the second hook is configured to receive a second end of the elastic band;
• wherein securing the elastic band at the first hook and the second hook provides tooth-moving forces as part of an orthodontic treatment plan;
• wherein the upper appliance comprises a locally reinforced portion connected with the first protrusion;
• and
• wherein the locally reinforced portion comprises a curved geometry.

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;
• a protrusion extending buccally from the plurality of teeth-receiving cavities;
• fabricating the orthodontic aligner based on the geometry determined, wherein fabricating the orthodontic aligner comprises:
• forming the plurality of teeth-receiving cavities and the protrusion together;
• removing material from the protrusion to form a hook;
• wherein the hook is configured to engage with an elastic band;
• wherein engaging the elastic band to the hook facilitates generating tooth-moving forces as part of the orthodontic treatment plan;
• wherein the geometry for the orthodontic aligner comprises a locally reinforced portion connected with the protrusion;
• and
• wherein the locally reinforced portion comprises a curved geometry.