Aligner manufacturing methods

A method of manufacturing multiple aligners simultaneously, the method comprising:

• determining a first size of a first mold of a first dental arch and a second size of a second mold of a second dental arch;
• selecting a first plate, a first sheet of plastic, and a first pallet based on at least one of the first size or the second size;
• causing the first mold and the second mold to be secured to the first plate;
• causing the first sheet of plastic to be heated, by a heater, to generate a first heated sheet, and causing the first sheet of plastic to be surrounded with a mask during heating of the first sheet of plastic to minimize heat transfer to other sheets of plastic and to substantially provide a thermal seal between the heater and the first sheet of plastic, wherein the mask is heat resistant up to about 500 degrees Fahrenheit;
• and
• causing the first heated sheet to be simultaneously thermoformed over the first mold of the first dental arch and the second mold of the second dental arch to form a first aligner shaped to fit the first dental arch and a second aligner shaped to fit the second dental arch.

A method comprising:

• causing a sheet of plastic to be secured between a pallet and a lower surface of a heat mask, an upper surface of the heat mask being coupled with a heater of an aligner manufacturing system, a plurality of inner sidewalls of the heat mask forming recesses, a first portion of the sheet of plastic being disposed on the pallet and exposed by the recesses of the heat mask, a second portion of the sheet of plastic being disposed on the pallet and covered by the heat mask;
• causing, via the heater, heat transfer to the first portion of the sheet of plastic to generate a heated first portion, wherein the heat transfer from the heater to the second portion of the sheet of plastic is minimized by the heat mask, wherein the heat mask is to substantially provide a thermal seal between the heater and the sheet of plastic, and wherein the heat mask is heat resistant up to about 500 degrees Fahrenheit;
• and
• causing the heated first portion of the sheet of plastic to be simultaneously thermoformed over a first mold of a first dental arch and a second mold of a second dental arch to form a first aligner shaped to fit the first dental arch and a second aligner shaped to fit the second dental arch.