Direct fabrication of orthodontic appliances with elastic regions
Methods for fabricating orthodontic appliances are provided. In some embodiments, a method includes directly fabricating a shell using an additive manufacturing technique. The shell can have an interior surface and an exterior surface. The interior surface can include a plurality of teeth-receiving cavities shaped to reposition a patient's dentition from a first arrangement toward a second arrangement. The method may also include directly fabricating an elastic region joined to the shell using an additive manufacturing technique, concurrently with directly fabricating the shell.
1 . A method for fabricating an orthodontic appliance, the method comprising:
directly fabricating a shell using an additive manufacturing technique, wherein the shell comprises:
an interior surface comprising a plurality of tooth-receiving cavities shaped to reposition a patient's dentition from a first arrangement toward a second arrangement,
an exterior surface disposed opposite the interior surface, and
a receptacle configured to accommodate an attachment coupled to a tooth of the patient; and
directly fabricating an elastic member joined to the shell using an additive manufacturing technique, concurrently with directly fabricating the shell, wherein the elastic member spans the receptacle, and wherein the elastic member is configured to impart a force on the attachment via the receptacle to reposition the tooth.
2 . The method of claim 1 , wherein the shell comprises a discontinuity, and the elastic member interacts with the discontinuity to reposition the patient's dentition from the first arrangement toward the second arrangement.
3 . The method of claim 2 , wherein the elastic member is an elongate elastic member having a first end coupled to a first portion of the shell, a second end coupled to a second portion of the shell, and an intermediate portion between the first and second ends that spans the discontinuity.
4 . The method of claim 2 , wherein the discontinuity comprises a cut in the shell, and wherein, when the shell is worn on the patient's dentition, the cut is stretched by placement of the shell on the patient's dentition.
5 . The method of claim 2 , wherein the discontinuity comprises a flap formed in the shell.
6 . The method of claim 1 , wherein the shell comprises a first shell section and a second shell section, and wherein the elastic member couples the first shell section to the second shell section.
7 . The method of claim 1 , wherein the shell comprises a plurality of shell segments, the elastic member comprises a plurality of elastic segments, and each elastic segment is coupled to a respective adjacent pair of shell segments.
8 . The method of claim 7 , wherein each elastic segment is directly coupled to the respective adjacent pair of shell segments.
9 . The method of claim 7 , wherein at least some of the plurality of elastic segments include a pre-loading force before the shell is placed on the patient's dentition.
10 . The method of claim 1 , wherein the elastic member comprises one or more elastic coatings on the exterior surface of the shell.
11 . The method of claim 10 , wherein the one or more elastic coatings have a variable thickness.
12 . The method of claim 10 , wherein the one or more elastic coatings form a single continuous layer covering the entirety of the shell.
13 . The method of claim 1 , wherein the shell is fabricated from a first material and the elastic region member is fabricated from a second material, the first material having a greater stiffness than the second material.
14 . The method of claim 1 , further comprising fabricating one or more auxiliary components formed in or coupled to the shell, the one or more auxiliary components comprising one or more of: a channel, a guide feature, a fastening feature, a flap, a retention feature, a telescoping feature, an interproximal feature, or a biasing feature.
15 . The method of claim 1 , wherein one or more of the shell or the elastic member is directly fabricated using vat polymerization, material jetting, binder jetting, material extrusion, powder bed fusion, sheet lamination, directed energy deposition, or a combination thereof.
16 . The method of claim 1 , wherein the receptacle comprises a lateral surface, and wherein the elastic member spans the lateral surface of the receptacle.
17 . The method of claim 1 , wherein the elastic member is stretched when the receptacle accommodates the attachment, and wherein the elastic member is configured to resist the stretching to impart the force on the attachment via the receptacle.
18 . The method of claim 1 , wherein the shell further comprises a retention feature coupled to the receptacle, and wherein the retention feature is configured to secure the elastic member at a specified position relative to the shell.
19 . The method of claim 18 , wherein the retention feature comprises a protrusion formed on the receptacle.
20 . The method of claim 1 , wherein the receptacle is a protrusion extending outward from the exterior surface of the shell.