Abstract: A removable dental appliance may include an appliance body at least partially surrounding two or more teeth of a patient. The appliance body may include a first shell shaped to receive a first tooth; a second shell shaped to receive a second tooth; and at least one spring bellows that includes an arcuate displacement extending over and away from at least a portion of an interproximal region between the first tooth and the second tooth to join the first shell and the second shell. The spring bellows is configured to apply a force between the first shell and the second shell to cause movement of at least one of the first tooth and the second tooth toward a desired position when the removable dental appliance is worn by the patient.

Abstract: A removable dental appliance may include an appliance body configured to at least partially surround a plurality of teeth of a dental arch of a patient. The appliance body may include a unitary material defining a shell shaped to receive at least one tooth of the patient and a spring member integrally formed with the shell. The spring member may be configured to receive an attachment. The attachment may be configured to affix to the at least one tooth. The spring member may be configured to apply a spring force to the attachment to cause at least one of a rotation, a translation, a tipping, a torqueing, an extrusion, or an intrusion of the at least one tooth toward a desired position of the tooth when the removable dental appliance is worn by the patient.

Abstract: An orthodontic palatal expander may include a first shell configured to receive at least one tooth of a first posterior segment of a dental arch of a patient; a second shell configured to receive at least one tooth of a second posterior segment of the dental arch; and a split beam connected between the first shell and the second shell. The split beam may include a first beam comprising a relatively high modulus material, a second beam comprising the high modulus material, and a region between the first beam and the second beam.

Abstract: A dental appliance includes a first polymeric shell portion having one or more cavities shaped therein to removably conform to one or more teeth. The dental positioning appliance further includes at least one spacer. At least one spacer is coupled to the first polymeric shell portion. The dental appliance can also have a first arch member coupled to the at least one spacer and configured to provide at least some of a force needed to reposition one or more teeth from a first orientation to a second orientation different from the first orientation.

Abstract: A method for determining virtual articulation from dental scans. The method includes receiving digital 3D models of a person's maxillary and mandibular arches, and digital 3D models of a plurality of different bite poses of the arches. The digital 3D models of the maxillary and mandibular arches are registered with the bite poses to generate transforms defining spatial relationships between the arches for the bite poses. Based upon the digital 3D models and transforms, the method computes a pure rotation axis representation for each bite pose of the mandibular arch with respect to the maxillary arch. The virtual articulation can be used in making restorations or for diagnostic purposes.

Abstract: The present invention is directed to computer-implemented methods of making a transfer tray using rapid prototyping techniques, where the gingival edge of the tray is defined to intersect with at least one receptacle for receiving an orthodontic appliance. This tray configuration helps to minimize the travel distance of the tray when placing the tray over a patient's teeth, while also preserving a high degree of mechanical retention for retaining the appliance until such time that the appliance is bonded to the tooth. Other aspects of the tray and associated methods of bonding are directed to a frangible web that extends over the gingival portion of the receptacle and fractures to facilitate tray removal after bonding.

Abstract: An orthodontic bracket is provided, which comprises an outer body, an elastomeric inner body coupled to the outer body, and a bracket base configured to couple to a tooth. The inner body of the outer body is disposed between the outer body and the bracket base. In an embodiment, a removable dental appliance comprises a plurality of polymeric shell portions each having one or more cavities shaped therein to receive one or more teeth and wherein each of the plurality of shell portions is formed to be separate from the other plurality of shell portions, wherein the bracket base is a polymeric shell portion.

Abstract: An orthodontic bracket is provided, comprising a bracket body configured to couple to an arch member and a first bracket footing disposed adjacent the bracket body. The first bracket footing has at least one major surface that is configured to mate with a receptacle formed from a bracket base, and extends beyond a plane formed by a major surface of the bracket body. In an embodiment, the base can be configured as a polymeric shell portion that is part of a removable dental appliance, wherein the polymeric shell portion can have one or more cavities shaped to receive one or more teeth.

Abstract: A method includes receiving, with a computer system, a digital representation of a 3D tooth structure providing initial positions of one or more teeth of a patient, determining dimensions and shapes of a removable dental appliance, the dimensions and shapes being configured to reposition the one or more teeth from their initial positions to adjusted positions when the dental appliance is worn, and transmitting a representation of the dental appliance to a computer-aided manufacturing system. The dental appliance includes an appliance body configured to surround two or more teeth of the patient with a facial portion configured to register with facial sides of the surrounded teeth, and a lingual portion configured to register with lingual sides of the surrounded teeth. The appliance body is configured such that occlusal surfaces of the surrounded teeth of the patient are exposed when the removable dental appliance is worn by the patient.

Abstract: A method for determining virtual articulation from dental scans. The method includes receiving digital 3D models of a person's maxillary and mandibular arches, and digital 3D models of a plurality of different bite poses of the arches. The digital 3D models of the maxillary and mandibular arches are registered with the bite poses to generate transforms defining spatial relationships between the arches for the bite poses. Based upon the digital 3D models and transforms, the method computes a pure rotation axis representation for each bite pose of the mandibular arch with respect to the maxillary arch. The virtual articulation can be used in making restorations or for diagnostic purposes.

Abstract: Methods for recognizing a virtual tooth surface, defining a virtual tooth coordinate system, and simulating a collision between virtual teeth are provided. Methods include receiving input data specifying a point on the rendered surface model associated with a tooth, deriving a perimeter on the surface model of the tooth based on the input data, and analyzing the surface model along a plurality of paths outwardly extending from points on the perimeter along the three-dimensional surface to produce gingival margin data. Methods also include receiving point input data that defines a point on the virtual tooth, receiving axis input data that defines first and second axes associated with the virtual tooth, computing a substantially normal vector for a portion of the tooth surface surrounding the point, and computing a coordinate system based on the axis input and the computed vector.

Abstract: A method for determining virtual articulation from dental scans. The method includes receiving digital 3D models of a person's maxillary and mandibular arches, and digital 3D models of a plurality of different bite poses of the arches. The digital 3D models of the maxillary and mandibular arches are registered with the bite poses to generate transforms defining spatial relationships between the arches for the bite poses. Based upon the digital 3D models and transforms, the method computes a pure rotation axis representation for each bite pose of the mandibular arch with respect to the maxillary arch. The virtual articulation can be used in making restorations or for diagnostic purposes.

Abstract: A method of forming an arch member comprising an arch member body and an arch member coupling integral with the body, comprising: providing a substrate comprising a resilient material; and removing a portion of the substrate to form the arch member. The arch member body including a cross-sectional geometry that varies along a length of the body. Also a method of designing an orthodontic appliance comprising: providing a proposed specification of the orthodontic appliance, wherein the orthodontic appliance comprises an arch member comprising an arch member body and an arch member coupling integral with the body, and a set of anchors, providing a first digital image representing a first dental arrangement associated with the orthodontic appliance; deriving a target digital image representing a target dental arrangement; revising the proposed specification of the orthodontic appliance based in part on the target digital image; and forming the orthodontic appliance based on the revised proposed specification.

Abstract: Various embodiments of an orthodontic appliance and method for forming such appliance are disclosed. The appliance can include a first anchor and a second anchor each including an anchor coupling and a base adapted to connect the respective anchor to a surface of a first tooth and a second tooth respectively. The appliance can also include an arch member including an arch member body and first and second arch member couplings integral with the body, the arch member body including a cross-sectional geometry that varies along a length of the body. The first arch member coupling can be releasably connectable to the anchor coupling of the first anchor and the second arch member coupling can be releasably connectable to the anchor coupling of the second anchor. The arch member body can include a first nonlinear portion between the first arch member coupling and the second arch member coupling.

Abstract: A method for determining virtual articulation from dental scans. The method includes receiving digital 3D models of a person's maxillary and mandibular arches, and digital 3D models of a plurality of different bite poses of the arches. The digital 3D models of the maxillary and mandibular arches are registered with the bite poses to generate transforms defining spatial relationships between the arches for the bite poses. Based upon the digital 3D models and transforms, the method computes a pure rotation axis representation for each bite pose of the mandibular arch with respect to the maxillary arch. The virtual articulation can be used in making restorations or for diagnostic purposes.

Abstract: A method includes receiving, with a computer system, a digital representation of a 3D tooth structure providing initial positions of one or more teeth of a patient, determining dimensions and shapes of a removable dental appliance, the dimensions and shapes being configured to reposition the one or more teeth from their initial positions to adjusted positions when the dental appliance is worn, and transmitting a representation of the dental appliance to a computer-aided manufacturing system. The dental appliance includes an appliance body configured to surround two or more teeth of the patient with a facial portion configured to register with facial sides of the surrounded teeth, and a lingual portion configured to register with lingual sides of the surrounded teeth. The appliance body is configured such that occlusal surfaces of the surrounded teeth of the patient are exposed when the removable dental appliance is worn by the patient.

Abstract: A removable dental appliance configured to reposition one or more teeth of a patient includes an appliance body forming an active band configured to surround two or more teeth of the patient. The appliance body includes a facial portion configured to register with facial sides of the surrounded teeth, a lingual portion configured to register with lingual sides of the surrounded teeth. The facial portion of the appliance body and the lingual portion of the appliance body form receptacles. Each receptacle is configured to accept at least one of the surrounded teeth. The receptacles separate the facial portion from the lingual portion at least along an anterior portion of the appliance body. The active band is configured such that occlusal surfaces of the surrounded teeth of the patient are exposed when the removable dental appliance is worn by the patient with the surrounded teeth positioned within the active band.

Abstract: The present invention is directed to computer-implemented methods of making a transfer tray using rapid prototyping techniques, where the gingival edge of the tray is defined to intersect with at least one receptacle for receiving an orthodontic appliance. This tray configuration helps to minimize the travel distance of the tray when placing the tray over a patient's teeth, while also preserving a high degree of mechanical retention for retaining the appliance until such time that the appliance is bonded to the tooth. Other aspects of the tray and associated methods of bonding are directed to a frangible web that extends over the gingival portion of the receptacle and fractures to facilitate tray removal after bonding.

Abstract: The present invention is directed to computer-implemented methods of making a transfer tray using rapid prototyping techniques, where the gingival edge of the tray is defined to intersect with at least one receptacle for receiving an orthodontic appliance. This tray configuration helps to minimize the travel distance of the tray when placing the tray over a patient's teeth, while also preserving a high degree of mechanical retention for retaining the appliance until such time that the appliance is bonded to the tooth. Other aspects of the tray and associated methods of bonding are directed to a frangible web that extends over the gingival portion of the receptacle and fractures to facilitate tray removal after bonding.

Abstract: Methods for recognizing a virtual tooth surface, defining a virtual tooth coordinate system, and simulating a collision between virtual teeth are provided. Methods include receiving input data specifying a point on the rendered surface model associated with a tooth, deriving a perimeter on the surface model of the tooth based on the input data, and analyzing the surface model along a plurality of paths outwardly extending from points on the perimeter along the three-dimensional surface to produce gingival margin data. Methods also include receiving point input data that defines a point on the virtual tooth, receiving axis input data that defines first and second axes associated with the virtual tooth, computing a substantially normal vector for a portion of the tooth surface surrounding the point, and computing a coordinate system based on the axis input and the computed vector.