Orthodontic Devices

Abstract

The orthodontic device (10) comprises a first opening (11) for receiving a first fixation structure, a second opening (12) for receiving a second fixation structure, and a third opening (13, 14, 15) for receiving a third fixation structure, the first fixation structure, and the third fixation structure being attached to the subject's mouth, and the orthodontic device (10) further comprises an intermediate structure (18) connecting the first opening, the second opening, and the third opening, one or more of the openings being stretchable, and the intermediate structure and the openings being made from a creep-resistant material. [Figure 1A]

Description

[Technical field]

[0001] [CROSS REFERENCE TO RELATED APPLICATIONS] This application claims the benefit of European Patent Application No. 20 382 367.9, filed May 4, 2021.

[0002] The present disclosure relates to orthodontic devices, and in particular to orthodontic devices that are attached to fixed structures such as brackets. The present disclosure further relates to kits and methods for orthodontic treatment. [Background technology]

[0003] Correcting misaligned teeth and bites by applying controlled forces to the teeth has become common. For example, the use of orthodontic brackets is well known. Orthodontic brackets are typically bonded directly to the front of each tooth and come in a variety of styles and sizes, including self-ligating, lingual, and titanium. The brackets act like handles that hold an archwire that moves the teeth. A single elastic or ligature is placed around the bracket that secures the archwire. Continued tooth movement requires monthly appointments to change or adjust the bands.

[0004] Orthodontic treatment including braces may be combined with the use of orthodontic "power chains". Orthodontic power chains comprise connected elastic ligatures that are often used to close spaces between teeth during orthodontic treatment. This method typically uses a series of connected elastic O-rings attached to brackets to create uniform tension across several teeth. The tension easily closes the spaces between teeth or groups of teeth and is typically used until the end of treatment. For example, US Pat. No. 5,399,433 disclosed an orthodontic force module made of an elastomeric material.

[0005] Orthodontists typically see patients once a month or once every few weeks. At each visit, the orthodontist will adjust the brackets as needed for treatment. Similarly, appropriate orthodontic power chains may be placed around the brackets during the visit.

[0006] Orthodontic power chains are usually made from silicone rubber. Silicone rubber is used in many medical applications and is therefore biocompatible. Also, silicone rubber has good elastic properties. When wearing an orthodontic power chain, a portion of the power chain is stretched. The openings of the power chain are placed around the brackets. The subsequent tension between the openings of the power chain forces the teeth closer together.

[0007] However, silicone rubber also has many drawbacks. First, the power chain loses its function or effectiveness fairly quickly, for example within a few days, under the influence of constant stress, saliva and humidity. Therefore, between visits to the orthodontist, the orthodontic power chain is not very effective. Also, the coloring of the power chain can be adversely affected under the influence of saliva. Furthermore, the friction between the silicone rubber and the metal bracket is relatively high, which adversely affects the effectiveness of the orthodontic treatment to solve the patient's occlusion malocclusion.

[0008] The use of coil springs is also known. Open coil springs are used when two teeth are too close together. The coil springs go over the archwire and are used to move the teeth away from each other. Closed coil springs may have eyelets on either end of the coil spring, which when extended, can pull the teeth closer together.

[0009] US Patent No. 5,399,663 discloses a variable extension spring having two fixed ends. US Patent No. 5,399,663 discloses an orthodontic tension assembly including a tensioner mount body having a first end and a second end, the first end of the tensioner mount body having an opening configured to removably receive a dental fixation structure and the second end of the tensioner mount body configured to removably couple a tensioning element.

[0010] The eyelet of the coil spring may be attached around a fixed point, such as a bracket attached to a tooth. When the coil spring is stretched during attachment, the natural tendency of the spring is to shorten, thus moving the teeth closer together. To pull multiple teeth closer together, multiple coil springs must be used simultaneously.

[0011] The present disclosure in various embodiments provides methods and devices for use in orthodontic treatment that at least partially address some of the problems discussed above. Summary of the Invention [Means for solving the problem]

[0012] In a first aspect, an orthodontic device is provided. The orthodontic device comprises a first opening for receiving a first fixation structure, a second opening for receiving a second fixation structure, and a third opening for receiving a third fixation structure, the first fixation structure, the second fixation structure, and the third fixation structure being mounted in a subject's mouth. The device further comprises an intermediate structure connecting the first opening, the second opening, and the third opening, one or more of the openings being stretchable, and the intermediate structure and the openings being made from a creep-resistant material. The orthodontic device may be configured to deform by increasing its length and decreasing its width.

[0013] According to this embodiment, the orthodontic device includes at least three openings for fitting around a fixed structure, such as a bracket. Thus, multiple teeth can be moved relative to one another. By making the orthodontic device from a creep-resistant material, the treatment can be much more effective than using silicone rubber. The function of the device can be maintained between visits to the orthodontist that are spaced 2-6 weeks apart. Also, the function can be maintained significantly longer than, for example, when the visits are spaced 2 months or more apart. In some cases, the same device can be used throughout the entire treatment period. One or more, or all, of the openings are stretchable and therefore deformable, i.e., they change shape when tension is applied. Thus, they can be fitted around various fixed structures in various parts of the mouth.

[0014] The orthodontic device is deformable, particularly by reducing the width of the structures, and by lengthening the structures. The device can be stretched without significantly distorting the material.

[0015] The orthodontic device may be deformable in the sense that the width of the device may be reduced, for example, by 25% or more, particularly 50% or more, when stretched to fit around a fixed structure, In some embodiments, the width of the device may be reduced by 70% or more when stretched to fit around a fixed structure.

[0016] Creep, as used throughout this disclosure, is the tendency of a solid material to move slowly or permanently deform under the influence of sustained mechanical stress. This can occur as a result of exposure to high levels of stress for extended periods of time, even below the material's yield strength. Creep is most pronounced in materials exposed to heat for extended periods of time, and generally increases near the melting point. Creep can occur in polymers and metals.

[0017] As used throughout this disclosure, a creep resistant material may be understood as a material that does not exhibit any significant creep behavior in the temperature range and moist environment of a user's mouth.

[0018] The opening and intermediate structure may be made from an elastic material.

[0019] As used throughout this disclosure, an elastic material may be understood as a material that allows for a high degree of deformation before it undergoes plastic deformation. In particular, its elastic limit, i.e., the amount of strain the material can withstand before plastic deformation occurs, may be 5% or more, specifically 10% or more.

[0020] In some embodiments, the material may be a superelastic metallic material.

[0021] In some embodiments, the superelastic metallic material may be Nitinol. Nickel titanium, also known as Nitinol, is a metallic alloy of nickel and titanium, where the two elements are present in approximately equal atomic percentages. Various alloys are named according to the weight percentage of nickel, for example Nitinol 55 and Nitinol 60. Nitinol 50 has 50% nickel and 50% titanium by weight. It exhibits shape memory effect and superelasticity at various temperatures. At body temperature, near 37°C, Nitinol typically exhibits superelastic behavior.

[0022] Depending on the alloy selected, the transition temperature may be high or low. In some embodiments, the alloy may be selected such that the transition temperature can be reached intermittently, for example at the level of 50° C. or 60° C. For example, when a patient drinks a cup of coffee or tea, the transition temperature is reached, and once that temperature is reached, the material of the device tends to return to its original shape. Thus, large fluctuations in force may occur temporarily.

[0023] In some cases, copper may be added to Nitinol, which can change the temperature at which the shape memory transition occurs.

[0024] In other embodiments, the device may be made from high performance thermoplastics such as polysulfone, polyphenylene sulfide (PPS), and polyketones, for example PEEK (polyetheretherketone).

[0025] In some embodiments, the device may be made from a single, integrally formed body. In some embodiments, the intermediate structures and openings may be formed by one or more woven or braided wires or wire bundles. In other embodiments, the orthodontic device may comprise a mesh. In embodiments where the openings and intermediate structures are formed from a single, integral body, hooks, or other attachments, contact between the components and the patient's cheeks, for example, may be avoided.

[0026] In a second aspect, an orthodontic device is provided that includes a first opening for receiving a first fixation structure, a second opening for receiving a second fixation structure, and a third opening for receiving a third fixation structure, the first fixation structure, the second fixation structure, and the third fixation structure being mounted in a subject's mouth. The device further includes an intermediate structure connecting the first opening, the second opening, and the third opening, the openings and the intermediate structure being made from a superelastic material, such as Nitinol. The orthodontic device may be configured to deform by increasing its length and decreasing its width.

[0027] In a third aspect, an orthodontic device is provided comprising a first opening for receiving a first fixation structure, a second opening for receiving a second fixation structure, and a third opening for receiving a third fixation structure, the first fixation structure, the second fixation structure, and the third fixation structure being mounted in a subject's mouth, the device further comprising an intermediate structure connecting the first opening, the second opening, and the third opening, the device reducing its width by 50% or more when mounted around the fixation structures.

[0028] In a further aspect, a kit is provided that includes an orthodontic device and a plurality of brackets. The orthodontic device includes a first opening for receiving a portion of a first bracket, a second opening for receiving a portion of a second bracket, and a third opening for receiving a portion of a third bracket. The device is made of a superelastic material, such as Nitinol. In use, the first, second, third (and further brackets) can be bonded to a patient's teeth. In use, the openings of the orthodontic device can be fitted around a portion of the brackets. The orthodontic device may be configured to deform by increasing its length and decreasing its width.

[0029] Any of the second, third and further aspects may be combined with any of the features disclosed herein by way of example with respect to the first aspect.

[0030] In any of these aspects, the first opening, the second opening, and the third opening (and optionally further openings) may be aligned along a longitudinal axis of the orthodontic device, the longitudinal axis of the orthodontic device extending between one end and an opposite end of the longitudinal axis. In particular, the first opening, the second opening, and the third opening may be aligned along a central longitudinal axis. The central longitudinal axis may form a longitudinal axis of symmetry. [Brief description of the drawings]

[0031] Non-limiting examples of the present disclosure are described below with reference to the accompanying drawings. [Figure 1A] 1A-1D are schematic diagrams illustrating two examples of orthodontic devices according to the present disclosure. [Figure 1B] 1A-1D are schematic diagrams illustrating two examples of orthodontic devices according to the present disclosure. [Figure 1C] 2A-2C show schematic diagrams of further embodiments of an orthodontic device; [Figure 2A] 2A-2C show schematic diagrams of further embodiments of an orthodontic device; [Figure 2B]2A-2C show schematic diagrams of further embodiments of an orthodontic device; [Figure 2C] 2A-2C show schematic diagrams of further embodiments of an orthodontic device; [Figure 3A] FIG. 10 shows a further embodiment further diagrammatically. [Figure 3B] FIG. 10 shows a further embodiment further diagrammatically. [Figure 4] 1A-1C are schematic diagrams illustrating an example of an orthodontic device placed around brackets in a patient's mouth. [Diagram 5] FIG. 1 illustrates generally some terminology in the orthodontic field. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0032] 5 is a schematic diagram of the arrangement of mandibular (lower jaw) teeth. The anterior portion of the mouth 110 may be referred to as the mesial region. The posterior portion of the mouth 120 may be referred to as the distal region. In orthodontics, mesial and distal are terms used to refer to what is closer to and further from the central midline of the dental arch, respectively.

[0033] In the distal region of the mouth, the molar region may be found. The molar region may include the first molar, the second molar, and possibly the third molar ("wisdom teeth"). The inner portion of the mouth behind the teeth 130 may be referred to as the lingual region (the region where the tongue is located). The outer portion of the mouth 140 may be referred to as the labial region (the region where the lips are located). The mesial-distal direction 115 for a particular tooth (the first molar) is shown diagrammatically in FIG. 1. Also shown in FIG. 5 is the lingual-labial direction 135 for the same tooth. This terminology will be adhered to in this disclosure.

[0034] Although the lower jaw is shown in this particular illustration, it will be apparent that the same terminology applies to the upper jaw as well.

[0035] FIG. 1A shows a schematic representation of a first embodiment of an orthodontic device 10. The orthodontic device 10 defines a longitudinal axis 200. The orthodontic device 10 comprises a first opening 11 for receiving a first fixing structure, a second opening 12 for receiving a second fixing structure, and a third opening 13 for receiving a third fixing structure. In this embodiment, there are additional openings 14, 15, 16 for receiving further fixing structures. All openings may be substantially aligned along the central longitudinal axis 200. The orthodontic device may be substantially symmetrical along the central longitudinal axis 200.

[0036] The first fixation structure, the second fixation structure, and the third fixation structure (and any additional structures) are attached in the subject's mouth. The fixation structures may be, for example, hooks placed on the patient's teeth, TADs (temporary anchorage devices), and / or (part of) brackets. In yet further embodiments, the fixation structures may be attachment portions of aligners (shells that fit around the dental arch). Brackets may, for example, have hooks that may be used as fixation structures, although other possible fixation structures include, for example, wings placed around an archwire (channel), or other orthodontic appliances such as the Carriere Motion appliance®.

[0037] The orthodontic device 10 further comprises an intermediate structure connecting the first opening, the second opening, and the third opening, the first opening, the second opening, and the third opening are stretchable, and the device 10 is deformable. When a user pulls on either end of the device, the device 10 elastically deforms, i.e., returns to its original shape when the force is removed. When tension is applied, the openings 11, 12, 13 deform and flatten, i.e., become narrower and longer. Significant changes in the overall length of the device can occur without necessarily significant stretching of the material.

[0038] The intermediate structure and the opening may be made from an elastic material, particularly a superelastic metallic material.

[0039] The orthodontic device 10 of this embodiment is made from woven wire. The orthodontic device is made from a single, integrally formed body that avoids hooks, appendages, and attachments that can damage or injure the inside of the patient's mouth. The wire forms both the openings that can receive the fixation structures and the intermediate structures between the openings. In an alternative embodiment, a bundle of wires may be used instead of a single woven wire.

[0040] As used herein, weaving may be construed as any form of passing lengths or strands of material over or under one another and intertwining threads or wires to form a pattern. As used throughout this disclosure, weaving is meant to encompass, for example, braiding and knitting.

[0041] In this embodiment, the cross junctions 18 of the wires between the openings 11-15 are welded. Welding or soldering these cross junctions of the wires or wire bundles provides a fixed point and helps limit the elongation of the openings, thereby allowing the openings to maintain their original shape. In an alternative embodiment, one or more of these junctions where the wires cross may be secured by a silicone or metal ring. The ring around the junction may allow some displacement of the wires within the ring. A further alternative is for a portion of the wire to be twisted around another portion of the wire at the junction. To ensure that the junction stays in place, the junction may include a single or double twist.

[0042] In the embodiment of FIG. 1A, six openings are provided. Thus, the orthodontic device 10 may be fitted around an equal number of six different fixation points. In some embodiments, not all openings need to be fitted around the fixation structures. For example, only openings at the ends of the device may be used, or openings at the ends of the device and one or more openings in between.

[0043] FIG. 1B shows an example of an orthodontic device in a first, contracted or "folded" state, and the same device in a second, "expanded" state. The orthodontic device 20 may be manufactured, sterilized, packaged, and shipped to an orthodontist or dentist in a contracted state. The contracted state may be the natural state of the device, i.e., the state that the device would return to if there were no external forces on the device. The expanded state (which may also be referred to as the "extended" or "elongated" state) represents the device positioned about a fixed point in the patient's mouth.

[0044] In the embodiment of Fig. 1B, four openings 21, 22, 23, 24 are provided and the device 20 is made from a single wire or a single bundle of wires. The intermediate structures between the openings are formed by cross junctions of the wires or wire bundles, similar to the embodiment of Fig. 1A. Also, the openings and intermediate structures are again made from a single, integral structure. Also, in this embodiment, the openings are arranged along a central longitudinal axis 200. The orthodontic device has a central longitudinal axis of symmetry.

[0045] In contrast to the embodiment of Figure 1A, the wire cross junctions are not soldered or bonded in this embodiment. In the expanded state shown in Figure 1B, the fixation points are shown diagrammatically at either end of the device. As the device 20 expands to fit around the fixation structure, it will tend to shorten or contract to its natural state. This applies a force to move the fixation points closer together. If the fixation points are located on teeth in the same arch (i.e., upper or lower jaw), for example, this applies a force to move the teeth closer together.

[0046] In the embodiment of Figures 1A and 1B, all openings 11-16, 21-24 are formed by the intersection of wires, the wires or bundles of wires forming an endless loop.

[0047] In this embodiment, all the openings are substantially the same size. When these devices are elongated, the openings 11, 16, 21, 24 at the opposing ends may deform smaller than the central opening. That is, the openings 11, 16, 21 and 24 at the opposing ends remain wider and shorter than the central opening. In further embodiments, the openings may not all be the same size. In particular, the openings at the opposing ends may be narrower than other openings of the same device.

[0048] FIG. 1C shows a schematic representation of another embodiment of an orthodontic device. The orthodontic device of FIG. 1C is generally similar to the embodiment of FIG. 1B, including four openings 21-24 formed by the intersection of wires. In the embodiment of FIG. 1C, the orthodontic device is formed by welding two wires at their ends 26, 28. Between the ends, the two wires are woven in the sense described above. The openings at both ends of the device have pointed straight ends extending in the longitudinal direction compared to the central rounded opening. The longitudinal extensions may serve to extend or lengthen the orthodontic device, particularly the openings at both ends in the longitudinal direction.

[0049] 2A-2C show further embodiments of an orthodontic device. In the embodiment of FIG. 2A, two openings 31, 32 are provided at one end and a third opening 33 is provided at the opposite end. Between openings 32 and 33 is a helical coil spring that forms an intermediate structure between the second and third openings. The coil spring and openings may be made from Nitinol as previously described. The coil spring 35 may be welded, soldered or brazed at either end of the opening. The helical coil spring may have a greater ability to expand before plastic deformation than the purely braided structure of FIG. 1.

[0050] 2B is similar to FIG. 2A, but shows an alternative embodiment in which, instead of a single helical coil spring, two helical coil springs 34, 36 are provided between the first opening 31 and the second opening 32, and between the second opening 32 and the third opening 33. The unstretched connector between the first opening and the second opening (in this case a helical coil spring) may have a different length than the connector between the second opening 32 and the third opening 33 (in this particular embodiment a helical coil spring).

[0051] The embodiment of Fig. 2C is also slightly different. In this embodiment, four openings 41, 42, 43 and 44 are provided, each of which receives and fits around a fixed structure or point. The intermediate structure 46 between the third opening 43 and the fourth opening 44 is also formed by a spring. Instead of a coil spring, a serpentine spring is used. The serpentine spring may reduce the risk of injuring the inside of the patient's mouth.

[0052] Yet another alternative embodiment is shown in Figures 3A and 3B. Figure 3A shows a device 50 made of a Nitinol mesh structure in its "natural" or contracted state. The mesh forms both the openings and the intermediate structures connecting them. The mesh may be woven, knitted, or braided. The ends of the meshes 52, 54 may be welded.

[0053] Instead of welding the ends of the mesh, the ends may be glued.

[0054] Figure 3B shows the same device 50 in an expanded state. It is clear that a single device can have different expanded states; that is, depending on the particular application, the device may be stretched to different degrees to fit around the anchoring points. The example of Figure 3B shows three anchoring points: an anchoring portion 62 at one end, an anchoring portion 64 at the opposite end, and an intermediate anchoring portion 66.

[0055] One aspect of the mesh structure, such as that shown in Figure 3, is that it contains many openings that can potentially be attached to different fixation structures, making the mesh structure extremely versatile and suitable for a wide variety of treatments.

[0056] Figure 4 shows an example implementation of an orthodontic device similar to the example of Figure 1, i.e., a device in which the apertures and intermediate structures are formed by braiding or weaving wires or bundles of wires. The implementation shown resembles a conventional use as an orthodontic power chain.

[0057] FIG. 4 shows how the openings 21-24 of the device 20 can be fitted around different anchoring structures. FIG. 4 shows a portion of the maxillary teeth 81, 83, 85, 87, 89. Brackets 91, 93, 95, 97, 99 can be bonded to successive teeth. The brackets 95, 97 and 99 are used as anchoring structures, and in particular the wings surrounding the archwire slots function as anchoring structures. Thus, the teeth 85, 87 and 99 are drawn together.

[0058] Bracket 93 and tooth 83 are not used as fixed structures. It is clear that it is not necessary to use all consecutive brackets, depending on the needs of the particular treatment. By widening the space between the openings (and thus greatly stretching the intermediate structure between the two openings), the pulling force can be increased.

[0059] In any of the embodiments disclosed herein, the anchoring points or structures may be part of a bracket, such as a hook, or a molar tube, or may be wings disposed around an archwire slot. In all of the embodiments shown herein, the openings of the device for receiving the anchoring structures are at least partially rounded, i.e., a portion of the opening is substantially circular, spherical, brow-shaped, or elliptical.

[0060] In any of the embodiments disclosed herein, the wires or wire bundles forming the openings or / mesh may have varying cross sections. Also, the cross section may not be constant along the entire device. The cross section may vary both in size and shape. Varying the cross section may provide localized weaknesses of localized stiffness so that the orthodontic device deforms in a coordinated manner.

[0061] In any of the disclosed embodiments, the openings configured to receive the anchoring structures may be aligned substantially along a longitudinal axis of the orthodontic device, i.e., the center point of each of the openings may be substantially on the longitudinal axis, in particular on the central longitudinal axis.

[0062] While only certain embodiments are disclosed herein, other alternatives, modifications, uses, and / or equivalents are possible. Moreover, all possible combinations of the described embodiments are covered. Thus, the scope of the disclosure should not be limited by the specific embodiments, but should be determined solely by a fair reading of the appended claims. [Prior art documents] [Patent documents]

[0063] [Patent Document 1] US Patent Application Publication No. 2004 / 0096798 [Patent Document 2] US Patent Application Publication No. 2012 / 0058444 [Patent Document 3] US Patent Application Publication No. 2007 / 0196781

Claims

1. 1. An orthodontic device formed from a single, integrally formed body including a first opening for receiving a first fixation structure, a second opening for receiving a second fixation structure, and a third opening for receiving a third fixation structure, the first fixation structure, the second fixation structure, and the third fixation structure are placed in a mouth of a subject; the orthodontic device comprising an intermediate structure connecting the first opening, the second opening, and the third opening; the intermediate structure and the opening are formed by a woven single wire or a woven single wire bundle of a superelastic metallic material; An orthodontic device, wherein one or more of the openings are expandable, and wherein the orthodontic device is configured to deform by increasing its length and decreasing its width.

2. The orthodontic device of claim 1 , wherein the superelastic metallic material is Nitinol.

3. The orthodontic device of claim 1 or 2, wherein one or more cross joints of the wires are welded.

4. 4. The orthodontic device of claim 1, wherein the orthodontic device is formed from a single wire.

5. 5. The orthodontic device of claim 1, wherein the orthodontic device is configured to reduce a width of the orthodontic device by 50% or more when the orthodontic device is fitted around the first fixed structure, the second fixed structure, and the third fixed structure.

6. 6. The orthodontic device of claim 1, wherein the first opening, the second opening, and the third opening are aligned along a longitudinal axis of the orthodontic device.

7. 7. The orthodontic device of claim 6, wherein the first opening, the second opening, and the third opening are aligned along a central longitudinal axis, and the orthodontic device is symmetrical along the central longitudinal axis.

8. 8. The orthodontic device of claim 1, wherein the intermediate structure comprises a first connector between the first opening and the second opening and a second connector between the second opening and the third opening, and in an unextended state, a length of the first connector is different from a length of the second connector.

9. 9. An orthodontic device according to any one of claims 1 to 8, comprising further openings for receiving further anchoring structures.

10. 10. A kit comprising a first bracket for attachment to a first tooth, a second bracket for attachment to a second tooth, and a third bracket for attachment to a third tooth, the kit further comprising the orthodontic device of any one of claims 1 to 9, configured to be fitted around the first bracket, the second bracket, and the third bracket.

11. The kit of claim 10 , wherein the orthodontic device is configured to be fitted around hooks on the first bracket, the second bracket, and the third bracket.

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