Customized orthodontic appliance and method

A method of producing a customized orthodontic appliance, the orthodontic appliance comprising brackets fixed to teeth of a dental arch of a patient, each bracket being fixed to a surface of a tooth of the dental arch by a bracket bonding pad of the bracket, and an orthodontic archwire fixed to the brackets in a housing of a bracket body of each bracket, the method comprising:

• constructing, by a processing device, a numerical representation of each bracket from a dental arch final numerical representation, the operation of constructing the numerical representation of each bracket comprising:
• positioning a numerical representation of an orthodontic archwire with respect to the dental arch final numerical representation, then for each tooth of the dental arch final numerical representation, positioning a second volume of a bracket blank comprising a first numerical representation of a volume representative of an envelope volume of a bracket body such that it interferes with the orthodontic archwire and in close proximity to the relevant tooth, and for each tooth of the dental arch final numerical representation, positioning a first volume of the bracket blank comprising a second numerical representation of a volume representative of an envelope volume of a bracket bonding pad such that it interferes with the second volume and with the volume of a relevant tooth, then determining, for each tooth in the first volume and in the second volume, volumetric exclusion zones which volumetric exclusion zones contain all of the volumes that interfere with the tooth for the first volume and all of the volumes that interfere with the orthodontic archwire for the second volume, wherein the numerical representation of the bracket of one tooth is determined by the volume of the bracket blank minus volumetric exclusion zones, wherein the volumetric exclusion zones of the first volume are defined in such a way as to determine a substantially constant thickness of the numerical representation of the bracket bonding pad;
• wherein the numerical representation of the bracket blank is chosen in relation to the shape of the relevant tooth so as to minimize the volume of the exclusion zones and wherein the numerical representations of the brackets are placed on lingual surfaces of the teeth of the dental arch final numerical representation;
• and
• wherein the numerical representation of the orthodontic archwire is positioned in such a way that a distance d, for each tooth of the dental arch final numerical representation, between the numerical representation of the orthodontic archwire and the surface of each tooth is greater than a minimum distance dmin that corresponds to a minimum thickness of the numerical representation of the brackets at their bracket bodies, and wherein, for each tooth of the dental arch final numerical representation, the numerical representation of the second volume is positioned in such a way that a reference point of the second volume corresponds to a point of intersection between the numerical representation of the orthodontic archwire and an orthogonal projection of a center of the relevant tooth.