Abstract: This invention is directed to a plastic orthodontic appliance having projecting structure extending outwardly from a bonding base. The projecting structure includes a broadened outer extremity and undercuts proximate the outer extremity which form mechanical bonds with a bonding adhesive. In one application, a plurality of appliances in the form of slotted brackets is provided for cooperating with an archwire to apply corrective forces to a patient's teeth on which the brackets are mounted. Another aspect of the invention concerns a method of making plastic orthodontic appliances suitable for mechanical bonding. The method includes molding a plastic orthodontic appliance having undeformed projecting structure and subsequently softening and compressing the outer extremity of the projecting structure to form undercuts. In a preferred embodiment, the projecting structure is a plurality of posts.

Abstract: An orthodontic bracket and ligature are provided in which the bracket, in the preferred embodiment, includes a cylindrical post, spaced from a bracket base to extend horizontally parallel thereto, and having an archwire slot therein. A spring material ligature band, naturally coiled and secured to a plastic installation strip, is pulled around the post of the bracket until a hooked trailing terminal end of the band catches on the bracket, pulling it loose from the strip, and allowing it to snap around the post to hold and confine the archwire in the slot. Different width ligatures seat to different positions on the post to allow the wire to be held to selected tightnesses in the slot by selection of the ligature.

Abstract: This invention is directed to a plastic orthodontic bracket reinforced with a metal insert having rotation wings. The bracket includes a protrusion extending into the archwire slot and having an upper end elevated above the bottom wall of the archwire slot. The upper end of the protrusion is adapted to contact the underside of an orthodontic archwire located in the archwire slot and to support at least a portion of the archwire above the bottom wall of the archwire slot.

Abstract: A method and apparatus for accurately positioning and orienting an orthodontic appliance relative to individual teeth of a patient is provided, preferably in the form of a pivot action jig, preferably of two parts pivotally linked together. Preferably, one part releasably engages an orthodontic bracket relative to a pivot axis at which the two parts are connected, preferably by fitting between spaced vertical tie wings of the bracket with a blade fitting in a bracket slot. The second jig part []includes a tooth-engaging surface configured to the shape of the crown of the tooth. Where the bracket itself is configured to pivotally attach to the jig, the jig may be formed of only the tooth engaging part. Preferably, the tooth-engaging surface uniquely fits over the occlusal end of the crown and includes a slight over center end, opposite the pivot connection, and may include a three-dimensional cap.

Abstract: A computerized method of designing custom orthodontic appliances based on the individual anatomy of the individual patient is used in a further method of statistically processing the appliance design parameters to produce standardized appliances, particularly orthodontic brackets, for patient groups or classes of patients that share certain features of dental anatomy, common treatment problems or similar preferred treatment goals. Standardized brackets are provided in various combinations for patients of racial or other anthropological groups, including bracket combinations and bracket sets for Asian patients and for Caucasian patients. Methods for treating patients and providing group specific appliances to patients are also provided.

Abstract: A model of the teeth in a patient's mouth and a prescription of desired positionings of such teeth are provided by the patient's orthodontist. The contour of the teeth in the patient's mouth is determined, preferably digitally, from the model. Calculations, preferably digital, on the contour and the desired positionings of the patient's teeth are then made to determine the geometry (e.g. grooves) to be provided in brackets for receiving an arch wire to form an orthodontic brace. Such geometry is intended to provide for the disposition of the arched wire on the brackets in a progressive curvature in a horizontal plane and a substantially linear configuration in a vertical plane. The geometry of the brackets is altered (e.g. by cutting grooves in the brackets at individual positions and angles and with particular depths) in accordance with such calculations of the bracket geometry. The brackets may be disposed on the model of the patient's teeth at positions dependent upon such calculations.

Abstract: A low profile orthodontic appliance and method of designing custom and standard low profile orthodontic appliances are provided. The archwire of the appliance is not parallel to the dental archform but converges toward the archform preferably in the vicinity of the incisors. Slotted brackets on either the laterals, the cuspids or the first bicuspids have mesially rotated slots to support the archwire in sloped relation to the teeth. For standardized appliances, the slot rotation may be provided only in brackets for the upper laterals and the lower cuspids. For Caucasians, the preferred rotation angles are 4.5 and 6 degrees respectively. For Asians, the rotation angles are preferably distributed over brackets for the laterals, cuspids and first bicuspids. Tooth to archwire spacing is not more than 0.05 inches for all teeth but the upper laterals.

Abstract: An orthodontic bracket, preferably in the form of a buccal tube, is provided for connecting an orthodontic archwire to each mandibular first molar of a patient. The bracket has an archwire groove oriented to maintain the archwire at a positive rotation angle relative to the point on the surface of the molar at which the bracket is connected. The rotation angle is preferably approximately 2.degree. for Caucasian patients and approximately 4.degree. for Asian patients. The groove, while inclined to a positive (distal) rotation angle of greater than zero, may additionally be inclined mesially relative to the wire to account for smaller cross-sectional dimensions of the wire relative to the groove. In making a custom orthodontic appliance, a computer designs such buccal tubes with the grooves rotated to an angle optimally calculated for the patient.

Abstract: Coordinated orthodontic archwires are provided based on a method of designing custom orthodontic appliances based in individual patient anatomy and, based on a plurality of such custom designs, designing and manufacturing a standardized appliance for patients of average dental anatomy. From such method, a relationship is established for coordinating one archwire to another of any given design. The coordinated archwires so provided include an upper archwire that is an expansion of a lower archwire, and in addition, when the shapes of the archwires are superimposed, are spaced apart more in the vicinity of the cuspids and first bicuspids than in the vicinity of the incisors and, preferably, also the second bicuspids. The spacing difference is at least 0.005 inches, particularly for an appliance with low profile brackets, and is up to 0.025 or 0.035 inches for an appliance with the more conventional brackets. The spacings are determined as a function of the length of the wire from the midline of the wire.

Abstract: Custom orthodontic brackets are provided for supporting an orthodontic archwire at custom positions and inclinations on the teeth of a patient. The preferred brackets each include a bracket base mountable on a tooth and a support extending therefrom for supporting an archwire, preferably in a slot of the custom inclination, depth and preferably curvature with respect to the mounting surface of the bracket base to the tooth. In the preferred embodiment, the brackets are formed by mounting blanks on an inclinable holder, positioning a cutter blade and inclining the holder to cut a custom slot in an archwire plane through the support on the bracket. The cutting tool and bracket holder are computer controlled and driven by signals produced from digitized data relating to the individual patient's anatomy, and preferably to tooth finish positions and bracket and archwire geometry calculated from digitized data taken from the patient's mouth or model thereof.

Abstract: A custom orthodontic appliance, preferably including an archwire, is automatically formed into an arcuate shape optimized to the anatomy of the patient to move the teeth to desired finish positions on a desired dental archform. Data, digitized of anatomical shapes, preferably of individual teeth and the lower jaw bone, is processed with data of the desired tooth positions and archform, which are preferably calculated from the digitized anatomical shape data, to design an optimized arcuate appliance. Preferably, an archwire is automatically designed along with optimized custom brackets to minimize bracket profiles and the changes in curvature of the wire, which is preferably in the form of a series of circle segments, embodied in machine control instructions carried by a control signal to a numerically controlled wire feeding and bending machine.

Abstract: A system and method by which an orthodontic appliance is automatically designed and manufactured from digital lower jaw and tooth shape data of a patient provides for preferably scanning a model of the patient's mouth to produce two or three dimensional images and digitizing contours and selected points. A computer is programmed to construct archforms and calculate finish positions of the teeth, then to design an appliance, preferably including archwires and brackets, to move the teeth to the calculated positions. The lower teeth are positioned at their roots on an arch defined by the lower jaw bone, and the arch is modified to best fit the tooth tips on a smooth curve. Then upper archforms are constructed for the upper teeth. Crown long axes of the teeth are derived and preserved in the treatment which places all lower teeth but the cuspids in a plane and fits the occluding teeth to them. Overlaps for the upper incisors and for cuspid rise are calculated.

Abstract: Contours of a patient's teeth are digitally determined from individual teeth of a model of the patient's mouth provided by an orthodontist, preferably by scanning individual teeth in a lingual-facial plane on the model with a mechanical probe. Tooth prominence parameters including tooth-gum intersections, mesial cusp tips or lingual and facial incisal edge points, and groove/ridge locations are selected on the contours. Tooth long axes are derived therefrom in the contour plane through the gum intersection and incisal edge/cusp tip midpoints and the contours are oriented to in the plane to predetermined inclination angles.

Abstract: A dental bracket is made from an alloy of nickel, beryllium and chromium. The alloy may be that designated by the trademark REXILLIUM III. A groove is disposed in one surface of the bracket to receive an arch wire. An opposite surface of the bracket is roughened to receive an adhesive which has properties of adhering to the bracket and to a patient's tooth. The bracket is formed by heating the alloy to the molten state, pouring the molten alloy into a mold with a cavity in the shape of the bracket and allowing the bracket to cool in air to room temperature. As the bracket cools, the beryllium oxide formed during the heating of the alloy is formed into dendrites. The surface receiving the adhesive is washed with an acid to remove the material in the space between the dendrites and thereby roughen the surface for the reception of the adhesive. The dental bracket is advantageous in that it is made from a single integral piece of material and in that it has properties of preventing tarnishing when scratched.

Abstract: Orthodontic appliance placement jigs are provided positioning and orienting the appliance at connection points on the teeth of a patient, particularly for positioning brackets against the surfaces of the teeth so that they can be bonded thereto. The jigs are each provided with a surface conforming to the contour of the tooth to which they are to be mounted. Another surface of the jig engages the bracket to hold it in the proper position and orientation for mounting to the tooth and spaced in relation to the contour surface to precisely locate the jig on the tooth. The jigs are particularly useful in positioning brackets of custom appliances designed to the individual anatomy of the patient, and requiring custom positioning of the brackets on the teeth. The jigs are formed with numerical controlled machinery that develops jig forming instructions from digitized tooth shape data and from digital representations of the tooth finish positions and appliance design.

Abstract: A dental bracket is made from an alloy of nickel, beryllium and chromium. The alloy may be that designated by the trademark REXILLIUM III. A groove is disposed in one surface of the bracket to receive an arch wire. An opposite surface of the bracket is roughened to receive an adhesive which has properties of adhering to the bracket and to a patient's tooth. The bracket is formed by heating the alloy to the molten state, pouring the molten alloy into a mold with a cavity in the shape of the bracket and allowing the bracket to cool in air to room temperature. As the bracket cools, the beryllium oxide formed during the heating of the alloy is formed into dendrites. The surface receiving the adhesive is washed with an acid to remove the material in the space between the dendrites and thereby roughen the surface for the reception of the adhesive. The dental bracket is advantageous in that it is made from a single integral piece of material and in that it has properties of preventing tarnishing when scratched.

Abstract: Apparatus is provided for resetting the position of teeth in a patient's mouth to a desired configuration where each tooth requires an individual magnitude of force, dependent upon the positioning of such tooth in the patient's mouth, to reset such tooth to the desired configuration. The apparatus includes a plurality of bracket assemblies each including a support member and a pad. Each pad is adhered to an individual one of the patient's teeth and to the associated support member. A groove is provided in each of the support members. An arch wire extends through the groove in each of the support members for retention in the groove. The arch wire has at each groove a thickness (or cross-sectional area) dependent upon the individual magnitude of force to be applied to the associated tooth.

Abstract: A model of the teeth in a patient's mouth and a prescription of desired positionings of such teeth are provided by the patient's orthodontist. The contour of the teeth in the patient's mouth is determined, preferably digitally, from the model. Calculations, preferably digital, on the contour and the desired positionings of the patient's teeth are then made to determine the geometry (e.g. grooves) to be provided in brackets for receiving an arch wire to form an orthodontic brace. Such geometry is intended to provide for the disposition of the arched wire on the brackets in a progressive curvature in a horizontal plane and a substantially linear configuration in a vertical plane. The geometry of the brackets is altered (e.g. by cutting grooves in the brackets at individual positions and angles and with particular depths) in accordance with such calculations of the bracket geometry. The brackets may be disposed on the model of the patient's teeth at positions dependent upon such calculations.

Abstract: First and second members are constructed to be disposed in an individual's body without adversely affecting the functioning of the individual's body. The first and second members may be illustratively an orthodontic bracket and an orthodontic pad. An armorphous alloy is disposed between or adjacent to the first and second members in a thin layer (e.g. three thousandths of an inch (0.003")) and is bonded, as by brazing, to the first and second members. The alloy is provided with properties of not affecting the functioning of the individual's body adversely. The alloy preferably has eutectic properties and has properties of being ductile and corrosion resistant. The alloy is preferably a metallic glass in which the primary element may be palladium. The alloy may consist of palladium, nickel and silicon.

Abstract: A method for determining orthodontic bracket placement on a malocclused tooth to correct the malocclusion includes the steps of generating digital information which defines the shape and location of the malocclused tooth in the patient's jaw, from which digital information a mathematical model of the tooth and jaw is generated. The correct placement position of a bracket is then calculated from the digitized information. A standard bracket is thereafter modified, if desired, individually for the patient, in view of the patient's physical deviations from the statistical averages. The shape of a bracket positioning jig is calculated and formed. Another step is forming an archwire for the brackets. The method may be used on one or more teeth in the same dental arch, as well as for both dental arches with respect to malocclusion therebetween.