RETENTIVE ORTHODONTIC DENTAL APPLIANCES AND METHODS OF MAKING SAME

Abstract

The present invention relates to retentive orthodontic dental appliances and methods for making same. The retentive orthodontic dental appliances of the present invention comprise structures formed on, and/or in, the tooth abutting surfaces of the base portions thereof to facilitate the bonding of the appliances to the surface of teeth with an adhesive. In embodiments of the present invention, at least a portion of the base portions of the appliances is substantially permeable to air and substantially impermeable to adhesive and is configured to allow air to permeate through the base portion when the appliance is being adhered to the tooth.

Claims

1. An orthodontic appliance comprising: a base portion having a tooth abutting surface and an opposite outer surface, said tooth abutting surface for adhering to a tooth; a body portion extending from said base portion in a direction away from said outer surface, said body portion for receiving an archwire; said base portion comprising at least one cavity for accommodating an adhesive and forming a lock between said appliance and said adhesive when said adhesive cures, said at least one cavity extending into said base portion away from said tooth abutting surface toward, but not through to, said opposite outer surface; wherein at least a portion of said base portion is substantially permeable to air and substantially impermeable to said adhesive and is configured to allow air to permeate through said base portion when said appliance is being adhered to said tooth.

2. The orthodontic appliance according to claim 1, wherein said at least one cavity decreases in dimension in a direction away from said tooth abutting surface.

3. The orthodontic appliance according to claim 1, wherein said at least one cavity increases in dimension in a direction away from said tooth abutting surface.

4. The orthodontic appliance according to claim 1, wherein said at least one cavity comprises a substantially circular depression in said tooth abutting surface.

5. The orthodontic appliance according to claim 1, wherein said at least one cavity has at least one pore through which excess adhesive may flow when the appliance is being adhered to said tooth.

6. The orthodontic appliance according to claim 1, wherein said at least one cavity is a plurality of cavities.

7. The orthodontic appliance according to claim 6, where said plurality of cavities are arranged longitudinally parallel in said tooth abutting surface.

8. The orthodontic appliance according to claim 6, wherein said plurality of cavities are arranged horizontally parallel in said tooth abutting surface.

9. The orthodontic appliance according to claim 6, wherein said plurality of cavities is provided by a mesh screen.

10. The orthodontic appliance according to claim 1, wherein said at least a portion of said base portion that is substantially permeable to air is at least one passageway that extends from said tooth abutting surface to said opposite surface.

11. The orthodontic appliance according to claim 10, wherein said at least one passageway is located in said at least one cavity.

12. The orthodontic appliance according to claim 10, wherein said at least one passageway includes at least one tapered portion that decreases in cross-sectional area as said outer surface is approached.

13. The orthodontic appliance according to claim 10, wherein said at least one passageway is tortuous.

14. The orthodontic appliance according to claim 10, wherein said at least one passageway contains an element extending in said at least one passageway that is substantially permeable to air and substantially impermeable to said adhesive.

15. The orthodontic appliance according to claim 14, wherein said element closes at least a portion of said at least one passageway.

16. The orthodontic appliance according to claim 14, wherein said element is fixed in said at least one passageway.

17. The orthodontic appliance according to claim 10, wherein said at least one passageway also extends through said body portion.

18. The orthodontic appliance according to claim 17, wherein said at least one passageway extends through a central portion of said body portion.

19. The orthodontic appliance according to claim 10, wherein said at least one passageway is a plurality of passageways.

20. The orthodontic appliance according to claim 10, said at least one passageway comprises at least one additional passageway extending at an angle relative to the direction of extension of said at least one passageway wherein said at least one additional passageway is substantially permeable to air and substantially impermeable to said adhesive.

21. The orthodontic appliance according to claim 20, wherein said at least one additional passageway extends in a direction perpendicular to the direction of extension of said at least one passageway.

22. The orthodontic appliance according to claim 1, wherein the appliance is a bracket, buccal tube, cleat or button.

23. The orthodontic appliance according to claim 1, wherein the appliance is made by 3D-printing.

24-33. (canceled)

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0127] The present invention will be further understood from the following description with reference to the Figures, in which:

[0128] FIG. 1A shows a perspective view of the front surface of an orthodontic bracket of the present invention.

[0129] FIG. 1B shows a perspective view of the tooth abutting surface of an orthodontic bracket of FIG. 1A.

[0130] FIG. 2A shows an exploded view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0131] FIG. 2B shows a cross-sectional view of the tooth abutting surface of the orthodontic bracket of FIG. 2A.

[0132] FIG. 3A shows an exploded view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0133] FIG. 3B shows a cross-sectional view of the tooth abutting surface of the orthodontic bracket of FIG. 3A.

[0134] FIG. 4A shows an exploded view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0135] FIG. 4B shows a cross-sectional view of the tooth abutting surface of the orthodontic bracket of FIG. 4A.

[0136] FIG. 5A shows an exploded view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0137] FIG. 5B shows a cross-sectional view of the tooth abutting surface of the orthodontic bracket of FIG. 5A.

[0138] FIG. 6A shows an exploded view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0139] FIG. 6B shows a cross-sectional view of the tooth abutting surface of the orthodontic bracket of FIG. 6A.

[0140] FIG. 7 shows a cross-sectional view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0141] FIG. 8A shows an exploded view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0142] FIG. 8B shows a cross-sectional view of the tooth abutting surface of the orthodontic bracket of FIG. 8A.

[0143] FIG. 9A shows an exploded view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0144] FIG. 9B shows a cross-sectional view of the tooth abutting surface of the orthodontic bracket of FIG. 9A.

[0145] FIG. 10A shows a perspective view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0146] FIG. 10B shows a perspective view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0147] FIG. 11A shows a perspective view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0148] FIG. 11B shows a perspective view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0149] FIG. 12A shows a perspective view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0150] FIG. 12B shows a perspective view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0151] FIG. 13A shows a perspective view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0152] FIG. 13B shows a perspective view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0153] FIG. 14A shows a front view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0154] FIG. 14B shows a cross-sectional view of an orthodontic bracket of the present invention.

[0155] FIG. 15A shows a cross-sectional view of an orthodontic bracket of the present invention.

[0156] FIG. 15B shows a cross-sectional view of an orthodontic bracket of the present invention.

[0157] FIG. 16 shows a perspective view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0158] FIG. 17A shows a perspective view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0159] FIG. 17B shows a perspective view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0160] FIG. 18A shows a cross-sectional view of an orthodontic bracket of the present invention.

[0161] FIG. 18B shows a perspective view of the front surface of an orthodontic bracket of the present invention.

[0162] FIG. 19A shows a perspective view of the front surface of an orthodontic bracket of the present invention.

[0163] FIG. 19B shows a cross-sectional view of an orthodontic bracket of the present invention.

[0164] FIG. 20A shows a cross-sectional view of an orthodontic bracket of the present invention.

[0165] FIG. 20B shows a cross-sectional view of an orthodontic bracket of the present invention.

[0166] FIG. 21A shows a cross-sectional view of an orthodontic bracket of the present invention.

[0167] FIG. 21B shows a cross-sectional view of an orthodontic bracket of the present invention.

[0168] FIG. 22A shows a cross-sectional view of an orthodontic bracket of the present invention.

[0169] FIG. 22B shows a cross-sectional view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0170] FIG. 23A shows a cross-sectional view of an orthodontic bracket of the present invention.

[0171] FIG. 23B shows a cross-sectional view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0172] FIG. 24A shows a cross-sectional view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0173] FIG. 24B shows a cross-sectional view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0174] FIG. 24C shows a cross-sectional view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0175] FIG. 25A shows a cross-sectional view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0176] FIG. 25B shows a cross-sectional view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0177] FIG. 25C shows a cross-sectional view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0178] FIG. 26A shows a cross-sectional view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0179] FIG. 26B shows a cross-sectional view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0180] FIG. 26C shows a cross-sectional view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0181] FIG. 27A shows a cross-sectional view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0182] FIG. 27B shows a cross-sectional view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0183] FIG. 27C shows a cross-sectional view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0184] FIG. 28A shows a cross-sectional view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0185] FIG. 28B shows a cross-sectional view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0186] FIG. 28C shows a cross-sectional view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0187] FIG. 29A shows a cross-sectional view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0188] FIG. 29B shows a cross-sectional view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0189] FIG. 30A shows a cross-sectional view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0190] FIG. 30B shows a cross-sectional view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0191] FIG. 31A shows a front view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0192] FIG. 31B shows a front view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0193] FIG. 32A shows a front view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0194] FIG. 32B shows a front view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0195] FIG. 33A shows a front view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0196] FIG. 33B shows a front view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0197] FIG. 34A shows a front view of a portion of the tooth abutting surface of an orthodontic bracket of the present invention.

[0198] FIG. 34B shows a front view of a portion of the tooth abutting surface of an orthodontic bracket of the present invention.

[0199] FIG. 35A shows a front view of a portion of the tooth abutting surface of an orthodontic bracket of the present invention.

[0200] FIG. 35B shows a front view of a portion of the tooth abutting surface of an orthodontic bracket of the present invention.

[0201] FIG. 36A shows a front view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0202] FIG. 36B shows a front view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0203] FIG. 37A shows a front view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0204] FIG. 37B shows a front view of the tooth abutting surface of an orthodontic bracket of the present invention.

[0205] FIG. 38 shows a perspective exploded view of a portion of the tooth abutting surface of an orthodontic bracket of the present invention.

DETAILED DESCRIPTION OF CERTAIN ASPECTS

[0206] Orthodontic dental appliances in accordance with embodiments of the present invention are illustrated in FIGS. 1A-38. Turning to FIGS. 1A and 1B, an orthodontic dental appliance in accordance with an embodiment of the present invention is broadly designated by 10. The appliance 10 in this instance is an orthodontic bracket that has a base portion 12 and a body portion 14.

[0207] Although the appliance 10 depicted in FIGS. 1A and 1B is an orthodontic bracket, in accordance with the present invention, the appliance 10 may be any type of orthodontic dental appliance known to persons skilled in this art which is adhered to a tooth surface in conjunction with moving teeth or holding teeth in a particular position. Non-limiting examples of orthodontic dental appliances in accordance with the present invention include orthodontic brackets, buccal tubes, cleats, lingual buttons and the like or other devices that are directly bonded to a tooth surface.

[0208] The base portion 12 of the appliance 10 includes a mesial edge 16, a distal edge 18, a gingival edge 20 and an occlusal edge 22 and has a rear tooth abutting surface 24 for receiving adhesive, which is shaped to conform to the corresponding shape of the front surface of a tooth (not shown) to which the appliance 10 is affixed, and a front surface 26, opposite to the rear tooth abutting surface 24, which front surface 26, in one embodiment, may be substantially parallel to the rear tooth abutting surface 24 or, in another embodiment, may be substantially flat.

[0209] The rear tooth abutting surface 24 of the appliance 10 is adapted to attach the appliance 10 to the surface of a tooth by use of an adhesive. Any adhesive known to persons skilled in this art for adhering orthodontic dental appliances to teeth may be used in association with the appliances of the present invention, such as, for example, chemical cure or light cure adhesives, available from suppliers such as, for example, GAC Dentsply, Unitek, 3M and American Orthodontics. After preparing the surface of the tooth for direct bonding in any manner well-known to persons skilled in this art, the orthodontist applies appropriate adhesive to the tooth abutting surface 24 of the appliance 10, which is then fixed directly to the tooth.

[0210] The body portion 14 of the appliance 10 projects out from the front surface 26 of the base portion 12 and may or may not be integral with the base portion 12, as will be further discussed below. The body portion 14 may include two gingival tie wings 28 and two occulsal tie wings 30 which define an archwire slot 32 for receiving a typical orthodontic archwire or similar restraining means (not shown), which the orthodontist applies for corrective purposes. The gingival tie wings 28 and occulsal tie wings 30 may include a top flange which prevents the archwire secured around the base of the gingival tie wings 28 and occulsal tie wings 30 from slipping off. Thus, the gingival tie wings 28 and occulsal tie wings 30 can be useful as anchors for the archwire.

[0211] In an embodiment of the present invention, the base portion 12 and the body portion 14 can be integrally formed, or, alternatively, can be formed separately and subsequently attached together. If the base portion 12 and body portion 14 are made separately from each other, they may be made of the same or different materials and may be joined by any means known to persons skilled in this art, such as, for example, by welding, gluing or by a positive fit (e.g., a screw connection). In aspects, the base portion 12 and the body portion 14 may be shaped for mating with one another in one definite position, such as, for example, one may have the negative shape of the other.

[0212] In accordance with the present invention, the base portion 12 is provided with at least one cavity 34 formed in the rear tooth abutting surface 24 thereof. The at least one cavity 34 extends from the rear tooth abutting surface 24 into the thickness of the base portion 12, toward, but not protruding all the way through, the exposed front surface 26 of the base portion 12. The at least one cavity 34 may extend from the rear tooth abutting surface 24 into the thickness of the base portion 12 any depth known to persons skilled in this art that still maintains the integrity and strength of the base portion 12, as will be discussed in further detail below. The at least one cavity 34 is defined by cavity sides 36 and a cavity bottom 38, collectively termed the cavity walls.

[0213] As shown in FIGS. 2A-38, the tooth abutting surface 24 of the appliance 10 comprises at least one adhesive receiving cavity 34. In embodiments of the present invention, the tooth abutting surface 24 comprises a plurality of adhesive receiving cavities 34. In embodiments of the present invention wherein the tooth abutting surface 24 comprises a plurality of cavities 34, the tooth abutting surface 24 may comprise any number of cavities known to persons skilled in this art that still maintain the integrity and strength of the base portion 12. In embodiments of the present invention wherein the tooth abutting surface 24 comprises a plurality of cavities 34, each cavity 34 of the plurality of cavities 34, may extend from the rear tooth abutting surface 24 into the thickness of the base portion 12 the same distance or different distances. Likewise, some cavities 34 may extend the same distance into the tooth abutting surface 24 while other cavities 34 may extend different distances.

[0214] The cavities 34, depending on the depth and number, provide varying degrees of porosity to the base portion 12 by which the adhesive can permeate into the base portion 12.

[0215] The at least one cavity 34 or plurality of cavities 34 can have any shape known to persons skilled in this art that achieves the purpose of allowing the adhesive to penetrate into the base portion 12. The porous geometry of the at least one cavity 34 or plurality of cavities 34, imparts various strengths, surface areas, and/or other characteristics to the base portion 12. For example, these porous geometries can be used to control the shape, type, degree, density, and size of porosity within the structure of the base portion 12. In some embodiments, such porous geometric designs can be of a regular shape, such as, for example, circular, triangular, square, rectangular, dodecahedral, octahedral, tetrahedral (diamond), as well as many other various geometric shapes. In other embodiments, the porous geometries of the present invention may be configured to have irregular shapes where various sides and dimensions have little, if any, repeating sequences. In some embodiments, the porous geometry may assume a single geometry, such as, for example, in FIGS. 2A, 2B, 3A, 3B, 10A, 10B, 11A, 11B, 12B, 13A, 13B, 14A, 14B, 15A, 15B, 16, 17A, 17B, 18A, 20A, 20B, 21A, 22A, 22B, 23B, 24A, 24B, 25A, 25B, 25C, 26A, 26B, 26C, 27B, 27C, 28A, 29A, 30A, 30B, 31A, 31B, 32A, 33A, 33B, 34A, 37A and 38. In other embodiments, the porous geometry may assume a combination of any number of different geometries, such as, for example, in FIGS. 4A, 4B, 5A, 5B, 6A, 6B, 7, 8A, 8B, 9A, 9B, 12A, 19A, 21B, 23A, 24C, 27A, 28B, 28C, 29B, 32B, 34B, 35A, 35B, 36A, 36B and 37B). In comparison, certain porous geometries may have different mechanical performance than other porous geometries.

[0216] In some embodiments, the porous geometry of the present invention defines a cavity 34 that is smaller in dimension at the tooth abutting surface 24 than the dimensions of the internal cavity formed therein. In other embodiments, the porous geometry defines a cavity 34 that is larger in dimension at the tooth abutting surface 24 than the dimensions of the internal cavity formed therein. In still other embodiments, the internal size dimensions of the cavities 34 may alternate between smaller than, or larger than, the dimensions of the cavities 34 at the tooth abutting surface 24. In aspects, the alteration between smaller and larger cavities may be in a random sequence or a uniform sequence depending on the requirements of the appliance 10.

[0217] As discussed above, the porous geometry of the present invention provides for varying degrees of cavity depth, such as deep or shallow cavities 34. It is also contemplated that the depths of the cavities 34 can alternate. In aspects, these alternating cavity depths are created in a random orientation. In aspects, these alternating cavity depths are created in a uniform orientation.

[0218] In an embodiment, the spacing between the cavities may be uniform. In another embodiment, the spacing between the cavities may be random. In an embodiment, the spacing between the pores is from about 0.005 inches to about 0.020 inches.

[0219] It is contemplated that the tooth abutting face 24 may have regularly sized cavities and regularly spaced cavities. It is also contemplated that the tooth abutting surface 24 may have irregularly sized cavities in an irregularly spaced configuration. It is further contemplated that the tooth abutting surface 24 may have regularly sized cavities arranged in an irregularly spaced configuration.

[0220] In an embodiment, the orthodontic appliance 10 may have a gradient porosity. For example, the tooth abutting surface 24 may be very porous and as one moves away from the tooth abutting surface 24 into the base portion 12, the porosity may alter such that the porosity is increased or decreased, even until the porosity is almost zero. In aspects, the base portion 12 may be comprised of different layers having different gradients of porosity. For example, the tooth abutting surface 24 may having a porosity of about 80%, whereas another portion of the base portion 12 may have a porosity of about 50%. Of course, the present invention contemplates a situation where the porosity of the base portion 12 alters from position to position depending on the requirements of the appliance 10.

[0221] In some embodiments, the at least one cavity 34 formed in the rear tooth abutting surface 24 of the base portion 12 forms at least one protrusion, peg, projection and/or overhanging portion. The at least one protrusion, peg, projection and/or overhanging portion may have a root or stem section having a base integrally formed with the tooth abutting surface 24 and a head or apex section buccolingually extending from the root/stem section. As may be appreciated, each protrusion, peg, projection and/or overhanging portion may, on its own, present an undercut, or may be further deformed at its outer extremity, thereby forming an undercut, proximate the outer extremity, which undercut is adapted to receive adhesive, that once cures or hardens, forms a mechanical bond or interlock between the appliance 10 and the adhesive.

[0222] The terms projection, protrusion, peg, projection and overhanging portion, as used herein are used interchangeably and refer to any structure which extends outwardly from the tooth abutting surface 24 of the base portion 12 of the appliance 10. The at least one projection may take any regular or irregular shape or configuration known to persons skilled in this art and make take a variety of shapes and configurations so long as it does not substantially offset the structural integrity of the appliance 10.

[0223] As shown in FIGS. 8A, 8B, 9A, 9B, 17A, 17B, 18A, 33B, 34A, 35B and 38, the at least one cavity 34 is a plurality of cavities 34 in the form of a lattice structure. As shown in FIGS. 8A and 8B, the lattice configuration may be random. As shown in 9A, 9B, 17A, 17B, 18A, 33B, 34A, 35B and 38, the lattice configuration may be uniform. In aspects, the lattice configuration may be a combination of both random and uniform.

[0224] In an embodiment, the lattice structure may allow for the use of stronger adhesives as they may not rely on the bond between the adhesive and the appliance 10, but instead, may trap the appliance 10 and may only rely on the bond between the adhesive and the tooth. This may allow for penetration of the adhesive into the entire structure creating a stronger bond of the appliance 10 with the tooth by distributing the mechanical forces in all directions.

[0225] In the embodiments described herein, the lattice structure may provide for sufficient porosity (open area) so that the adhesive may be allowed to flow freely and virtually unrestricted through the appliance 10 to the tooth. Free flow of the adhesive may affect the ultimate bond strength between the appliance 10 and the tooth through increased grip. The adhesive is able work its way through the cavities 34 and may improve the displacement of forces about the tooth.

[0226] Advantageously, the lattice structures described herein may allow for the adhesive to flow around it before it is cured. This may strengthen the bond as it may not rely only on the bond between the appliance 10 and the adhesive, but the structure of the adhesive may encapsulate the appliance 10 as well. The lattice structure is strong and may transmit external forces in multiple directions to the adhesive and may lessen its ability to break the bond. Improved bonding properties may reduce the necessity for multiple orthodontic appointments.

[0227] As shown in FIGS. 9A and 9B, the lattice structure may be in the form of a round or square mesh structure. In aspects, the strands of the lattice are angled at about 90 to each other. In other aspects, the strands of the lattice are angled at about 10, about 15, about 20, about 25, about 30, about 35, about 40, about 45, about 50, about 55, about 60, about 65, about 70, about 75, about 80, or about 85 to each other.

[0228] In an embodiment of the present invention, the tooth abutting surface 24, including the at least one cavity 34 and/or the at least one projection, may be given an additional treatment, such as, for example, roughening, etching or scribing, a plasma treatment, a coating, such as, for example, a primer treatment or coated with a layer of particles, or by deforming the at least one projection in the lateral direction, in an effort to further enhance adhesion (see for example, FIGS. 15B, 16, 29B, 30A, 30B, 34B, 35A, 35B and 38).

[0229] In some embodiments, at least a portion of the base portion 12 of the appliance 10 is substantially permeable to air but substantially impermeable to adhesive. In some embodiments, the entire base portion 12 of the appliance 10, is substantially permeable to air but substantially impermeable to adhesive. The at least a portion of the base portion 12 that is substantially permeable to air and substantially impermeable to adhesive is configured to allow air to permeate through the base portion 12 when the appliance 10 is being adhered to the tooth. The portion of the base portion 12 that is substantially permeable to air and substantially impermeable to adhesive functions as a vent to enable air trapped in air pockets within the adhesive to escape. The vent, while enabling air to move through at least a portion of the base portion 12, hinders or substantially prevents movement of the adhesive through the base portion 12 as the appliance 10 is placed on the tooth surface, such that the necessity of clean-up of adhesive near the front surface 26 of the base portion 12 is avoided.

[0230] The at least a portion of the base portion 12 that is substantially permeable to air but substantially impermeable to adhesive can be formed by any suitable method known to persons skilled in this art, such as, for example, by way of the material used for the at least a portion of the base portion 12 that is substantially permeable to air but substantially impermeable to adhesive or by way of forming the at least a portion of the base portion 12 that is substantially permeable to air but substantially impermeable to adhesive in the base portion 12.

[0231] In some embodiments, the base portion 12 comprises a single vent which is substantially permeable to air but substantially impermeable to adhesive. In some embodiments, the base portion 12 comprises enough vents to result in substantially the entire base portion 12 substantially permeable to air but substantially impermeable to adhesive.

[0232] In some embodiments, the vent/vents is/are a hole/holes or a pore/pores, the cross section of at least a portion thereof is large enough to allow air to pass therethrough,thus making at least a portion of the base portion 12 substantially permeable to air but small enough to prevent adhesive from passing therethrough, thus making the base portion 12 substantially impermeable to adhesive.

[0233] In some embodiments, the cross-sectional shape of the vent/vents is such that adhesive is prevented from passing therethrough, thus making the base portion 12 impermeable to adhesive but allows air to pass therethrough, thus making at least a portion of the base portion 12 substantially permeable to air.

[0234] In some embodiments, the path of the vent/vents through at least a portion of the base portion 12, is such, for example, but not limited to, tortuous, that adhesive is prevented from passing therethrough, thus making the base portion 12 impermeable to adhesive but allowing air to pass therethrough, thus making at least a portion of the base portion 12 substantially permeable to air.

[0235] In some embodiments, the portion of the base portion 12 that is substantially permeable to air and substantially impermeable to adhesive is comprised of a material that is substantially permeable to air and substantially impermeable to adhesive.

[0236] In some embodiments, the portion of the base portion 12 that is substantially permeable to air is at least one passageway 40 that extends from said tooth abutting surface 24 to said opposite front surface 26. For example, as shown in FIGS. 4B, 5B, 6B, 9B, 18B and 19A, the tooth abutting surface 24 further comprises at least one passageway 40 that extends through the base portion 12 to the front surface 26. In some embodiments, the tooth abutting surface has a single passageway 40. In some embodiments, the tooth abutting surface 24 has a plurality of passageways 40. Since the presence of air bubbles in the adhesive may weaken the ability of the adhesive to bond the appliance 10 to the tooth, the passageways 40 are configured in such a way as to facilitate the escape of air trapped in pockets formed in the adhesive when the appliance 10 is applied to the tooth. In some embodiments, the at least one passageway 40 is located within the at least one cavity 34. In some embodiments, a plurality of passageways 40 are located within the at least one cavity 34. In some embodiments, the at least one passageway 40 follows a straight path. In some embodiments, the at least one passageway 40 follows a torturous path. In some embodiments, the at least one passageway 40 includes at least one tapered portion that decreases in cross-sectional area as said outer front surface 26 is approached. In some embodiments, the plurality of passageways 40 are arranged in an array. However, other arrangements and/or arrays are also possible. In some embodiments, the at least one passageway 40 integrally connects at least two cavities 34. In some embodiments, the at least one passageway 40 comprises at least one additional passageway extending at an angle relative to the direction of extension of the at least one passageway 40 wherein the at least one additional passageway is substantially permeable to air and substantially impermeable to adhesive. In some embodiments, the at least one additional passageway extends in a direction perpendicular to the direction of extension of the at least one passageway 40. In some embodiments, the at least one passageway 40 extends through a central portion of the base portion 12. Moreover, the passageways 40 may extend in other portions of the base portion 12, including side portions or alternatively portions that extend along the entire periphery of the base portion 12, if desired. The at least one passageway 40 and the at least one additional passageway may be formed by any method known to persons skilled in this art, such as, for example, by drilling, stamping, casting or by additive manufacturing such as 3D printing.

[0237] In some embodiments, the at least one passageway 40 contains an element extending in the at least one passageway 40 that is substantially permeable to air and substantially impermeable to adhesive. In some embodiments, the element closes at least a portion of the at least one passageway 40. In some embodiments, the element is fixed in the at least one passageway 40. In some embodiments, the element is removable from the at least one passageway 40. The element may be made from any material that is substantially permeable to air and substantially impermeable to adhesive known by persons skilled in this art and may be inserted into the at least one passageway 40 by any method known by persons skilled in this art, such as, for example, but not limited to, injecting. In some embodiments, the element may be a liquid, a semi-solid such as a gel or a solid when inserted into the at least one passageway 40. In some embodiments, the element may become a semi-solid or solid within the at least one passageway over time or upon curing. In some embodiments, the element may be made of In embodiments of the present invention, the at least a portion of the base portion that is selectively permeable or semi-permeable may be composed of silicone; rubbers; elastomers; cork; ceramics; polyethylene (PE) such as, for example, but not limited to, high density spun-bound polyethylene similar to that sold under the name Tyvek; polypropylene (PP) such as, for example, but not limited to, spun-bonded polypropylene fiber similar to that sold under the name Typar; microperforated polyethylene similar to that sold under the name Rufco-Wrap; polytetrafluoroethylene (PTFE or Teflon) such as, for example, but not limited to, stretched polytetrafluoroethylene similar to that sold under the name Gore-Tex; a silanized alumina; a molecular sieve material such as, for example, but not limited to, zeolites (aluminosilicate minerals), porous glass, active carbon, and clays; and a hydrophobic aerogel such as, for example, but not limited to, those based on silica, alumina, chromia, titania, zirconia, vanadia, samaria, holmia, erbia, carbon, cadmium selenide quantum dots, metal oxides such as, for example, but not limited to, aluminum oxide, tin dioxide, iron oxide, neodymium oxide, organic polymers such as, for example, but not limited to, agar or cellulose, and chalcogens (chalcogel) such as, for example, but not limited to, sulfur, selenium and other elements. The appliance 10 of the present invention may be made of any suitable material known to persons skilled in this art for its intended purpose, such as metals (e.g., stainless steel and titanium), ceramics (e.g., mono- or poly-crystalline alumina), plastics (e.g., filled and/or reinforced polycarbonate), porcelain, glass etc. It is contemplated that the appliance 10 can cover as much or as little of the tooth that is necessary, dependent on, for example, the size, shape and location of the tooth. It will be appreciated that a wide variety of appliance configurations are suitable in the practice of the present invention.

[0238] In an embodiment, the appliance 10 may be made of any suitable metal powder. The metal powder may be titanium alloys, stainless steel, cobalt chromium alloys, tantalum or niobium. It contemplated that the orthodontic appliance 10 may be made of any combination of the metal powders described above. In an embodiment, the metal powder is tantalum. The material, such as tantalum, used in these appliances is essentially inert to adhesives and body fluids so that chemical bonding, dissolution, discoloration, or degradation of the lattice structure does not occur.

[0239] It is contemplated that different metals can be used for the base portion 12 and the body portion 14, for example to provide a relatively hard body portion 14 for durably holding the archwire and to provide a softer base portion 12 to prevent the appliance 10 from breaking upon exposure of mechanical forces (for example during chewing action). Alternatively, the base portion 12 and the body portion 14 may be made of the same metal.

[0240] It is contemplated that appliance 10 may have a variety of possible prescriptive values of torque, tip, and angulation. For example, in one embodiment the appliance 10 can have an archwire slot that extends along an axis which is inclined by about 5 degrees relative to the longitudinal axis. Typically, the archwire slot can extend along an axis which is inclined by about 10, about 15, about 20, about 25, about 30, about 35, about 40, about 45, about 50, about 55, about 60, about 65, about 70, about 75, about 80, about 85 or about 90 degrees relative to the longitudinal axis.

[0241] The orthodontic appliances described herein can be made by any means known to persons skilled in this art. For example, conventional methodologies used for producing orthodontic appliances include, but are not limited to, investment casting, metal or ceramic injection molding, extrusion cutting or machining.

[0242] In an embodiment, the orthodontic appliance 10 is made by rapid prototyping or additive manufacturing (e.g., 3D printing). This typically involves producing the component by progressively adding or subtracting layers of material for direct or indirect fabrication. Fabrication is direct if it is performed notably by laser sintering; indirect if it is performed notably by the lost wax casting method. Using this method, a single customized appliance 10 may be produced more quickly than by machining or by some other method that calls for specialist tooling.

[0243] Production of the orthodontic appliance 10 using laser sintering and/or laser melting permits extensive automated production thereof, since a computer-aided laser is able to generate predefined shapes. The predefined forms are firstly determined with the help of a computer. Data obtained by scanning the patient's teeth or a dental cast of the patient's teeth are used as a basis for determining the optimal form of the orthodontic appliance 10. Furthermore, this method allows complex structures of virtually any shape and size to be produced. This method is particularly suitable in that complex porous geometries of the orthodontic appliance 10 can be easily produced.

[0244] In an embodiment, the tooth abutting surface 24 of the customized orthodontic appliance 10 is typically overall shaped to conform to a portion or area of the outer tooth surface. Typically, the tooth abutting surface 24 of the customized orthodontic appliance 10 has a footprint (or outer periphery) and the portion of the outer tooth surface corresponds in size and shape to that footprint. The term conform as used herein denotes that the overall shape of the tooth abutting surface 24 and the overall shape of the tooth portion correspond to each other, although a surface structure of the tooth abutting surface 24 may be different from the surface structure of the tooth. For example, the tooth abutting surface 24 comprises the at least one cavity 24 but still overall conforms to the shape of the tooth portion.

[0245] In an embodiment, the base portion 12 is made by additive manufacturing. In another embodiment, the body portion 14 is made by additive manufacturing. In another embodiment, both the base portion 12 and body portion 14 are made integral with one another through the use of additive manufacturing. In an embodiment, both the base portion 12 and the body portion 14 are initially pre-manufactured and subsequently joined, for example by assembly. The pre-manufactured body portion 14 typically has a base portion interface in the form of a surface for connection of the body portion 14 with the base portion 12. The base portion 12 and the body portion 14 may be joined by any known means of the art.

[0246] In a further embodiment, the method comprises the step of building up the base portion 12 on the body portion 14. The pre-manufactured body portion 14 also typically has a base portion interface in the form of a surface for connection of the body portion 14 with the base portion 12. The base portion interface is typically arranged opposite of the archwire slot. Further, the base portion interface is typically used in this embodiment for building up the base portion 12 thereon by a material build-up process.

[0247] In an embodiment, the method may further comprise the step of providing a primer layer on the body portion 14, in particular on the base portion interface of the body portion 14, and building up the base portion 12 on the primer layer. The primer layer may comprise a metal alloy and a flux melting agent. Thus, using for example Selective Laser Melting (SLM), a stable connection between the base portion 12 and the body portion 14 may be achieved.

[0248] In an embodiment, the method further comprises the steps of providing a plurality of differently shaped pre-manufactured physical body portions 14. Further, the step of providing the pre-manufactured physical body portions 14 according to the invention may comprise selecting a particular pre-manufactured physical body portion 14 out of the plurality of differently shaped pre-manufactured physical body portions 14 (e.g., body portions 14 having any of a variety of possible prescriptive valves of torque, tip and angulation) as herein described. Typically, the material build-up process is based on Selective Laser Melting (SLM), in particular Direct Metal Laser Sintering (DMLS).

[0249] It is also contemplated that the method may further comprise steps for determining the shape of the appliance 10 and in particular for determining the shape of the tooth abutting surface 24. The shape of the appliance 10 and/or the shape of the tooth abutting face 24 may be provided in a computer processible format and used in the material build-up process to make the appliance 10/tooth abutting face 24.

[0250] In an embodiment, a virtual model of the patient's dentition (upper and/or lower jaw) with the teeth in the initial positions may be obtained from scanning the actual teeth of the patient intra-orally, or from scanning a physical model (for example a plaster model cast from a dental impression) of the patient's teeth. In aspects, it is further possible to scan a dental impression taken from the patients teeth. The shape of the patient's dentition may be captured in the form of a three-dimensional computer model, referred to as a virtual malocclusion model.

[0251] An advantage of the method according to the present invention is thus first of all that a plastic tooth model is not necessary. If such a tooth model already exists, however, or is possibly produced for better visualization, this can likewise be used according to the present method described herein.

[0252] Typically, an area is identified on several of the patient's teeth within the virtual model. The identified area or a copy thereof may be used to define a virtual bonding surface of the appliance 10. In aspects, an area may be identified on the labial or lingual surface of individual teeth in the model. Such area is a representation of a physical area on a tooth on which a tooth abutting surface 24 of the appliance 10 may be bonded. Typically, the area is selected to be large enough to cover a sufficient area so that an orthodontist can place the appliance 10 on the corresponding tooth in one definite position. Typically, the area further covers approximately about 60 to about 75 percent of the labial or lingual surface of a tooth to provide both good adhesion and to facilitate correct positioning.

[0253] The skilled person will recognize that this can be done by computer operation, for example by Computer Aided Design (CAD) software allowing creation and manipulation of three-dimensional computer models. Further, the skilled person will recognize that the mentioned areas can be identified physically on the patients teeth or the model of the patient's teeth and captured to provide the virtual bonding surface.

[0254] Typically, the CAD system allows the tooth abutting surface 24 to be designed based on the determination of the virtual bonding surface. For example, the virtual bonding surface (or a copy thereof) may be used to form the shape of the tooth abutting surface 24 of the appliance 10 and an offset of the virtual bonding surface may be used as a rear side or outward-facing side (opposite of the tooth facing side) of the tooth abutting surface 24. A so formed computer design may be exported in the form of computer processible data to a material build-up device, for example an SLM device, in which the appliance 10 is completed as described above.

[0255] In an embodiment, the body portion 14 is placed in a three-dimensional material build-up device such as a Selective Laser Melting (SLM) device. Typically, the body portion 14 is placed at a determined reference position. Typically, the reference position comprises information about a position of the body portion 14 in a coordinate system of the device as well as an orientation of the body portion 14 in that coordinate system. In aspects, the body portion 14 is embedded in a metal powder, such as tantalum, with the base portion interface oriented toward the free surface of that powder. A thin layer of powder covers the base portion interface and a laser beam is used to sinter the base portion 12 layerwise onto the body portion 14. The positioning of the laser beam is computer numerically controlled in accordance with the virtual model of the base portion 12 and in appropriate geometric relationship to the body portion 14.

[0256] In aspects, the base portion 12 may be integrally formed with the body portion 14 during the additive manufacturing process. For example, the base portion 12 and the body portion 14 are staged and built up at the same location (e.g., generally the same x- and y-axis location) on the base plate. In aspects, the base portion 12 may be formed separately from the body portion 14 during the additive manufacturing process. For example, the base portion 12 is staged and built up at one location in the additive manufacturing system whereas the body portion 14 is staged and built up at another location on the base plate. The base portion 12 and the body portion 14 are then later joined together using methods known in the art.

[0257] In an embodiment, the method produces an orthodontic appliance 10, wherein the tooth abutting surface 24 has at least one adhesive receiving cavity 34. In another embodiment, the method produces an orthodontic appliance 10, wherein the tooth abutting surface 24 has a plurality of adhesive receiving cavities 34. In another embodiment, the method produces an orthodontic appliance 10 that is substantially porous. In another embodiment, the method produces an orthodontic appliance 10 that is completely porous.

[0258] In another embodiment, the method produces an orthodontic appliance 10, wherein each of the porosity, pore size and pore volume of the tooth abutting surface 24 is uniformly spaced on the tooth abutting surface 24. In another embodiment, the method produces an orthodontic appliance 10, wherein each of the porosity, pore size and pore volume is irregularly spaced on the tooth abutting surface 24. In aspects, the method produces an orthodontic appliance 10 having a gradient porosity as herein described. In aspects, the method produces an orthodontic appliance 10, wherein the tooth abutting surface 24 has a pore size as herein described. In aspects, the method produces an orthodontic appliance 10, wherein the tooth abutting surface 24 has a porosity as herein described. In aspects, the method produces an orthodontic appliance 10, wherein the tooth abutting surface 24 has a pore volume as herein described. In aspects, the method produces an orthodontic appliance 10, wherein the at least one adhesive receiving cavity 34 has a lattice configuration as herein described. In aspects, the method produces an orthodontic appliance 10, wherein the plurality of adhesive receiving cavities 34 have a lattice configuration as herein described.

[0259] The orthodontic appliance 10 can be manufactured using casting, metal injection molding, micromachining, any combination of generic mass production and customization techniques, and/or any direct digital manufacturing technique and by building up the material by additive methods, such as three-dimensional printing (3D printing), which can include, for example, rapid prototyping.

[0260] 3D printing (additive manufacturing) may be capable of producing stronger, more effective, and less expensive orthodontic appliances. Using this technology, the orthodontic appliance 10 of the present invention can be structured in lattices rather than solid pieces of metal, thereby improving fit, reducing weight and the comfort level experienced by the patient. Furthermore, a clear benefit of this technology is that the patient would be able to have tailor-made brackets by scanning their teeth and matching it with a metal 3D-printed replacement.

[0261] It will be understood that certain of the above-described structures, functions, and operations of the above-described embodiments are not necessary to practice the present invention and are included in the description simply for completeness of an exemplary embodiment or embodiments. In addition, it will be understood that specific structures, functions, and operations set forth in the above-described referenced patents and publications can be practiced in conjunction with the present invention, but they are not essential to its practice. It is therefore to be understood that the invention may be practiced otherwise than as specifically described without actually departing from the spirit and scope of the present invention as defined by the appended claims.