Method and system for manufacturing a retaining wire

Abstract

The present invention relates to a method and a system for manufacturing a retaining wire (11), said retaining wire (11) having a shape which is folded along the lingual surface of a set of teeth (12). To this end, a wire that is made of a shape-memory material and has a rectangular cross-section comprising a plurality of braided strands is assembled in the groove of a mould, said groove defining said folded shape. The shape-memory material is then activated.

Description

[0001] Description

[0002] Title: Process and system for manufacturing a retention wire

[0003] technical field

[0004] The present invention relates to the field of orthodontic wires, in particular retention wires.

[0005] The present invention relates more particularly to a method and system for manufacturing a support wire, as well as to an associated support wire.

[0006] The present invention will thus find many advantageous applications in the field of orthodontic treatments.

[0007] Previous art

[0008] After orthodontic treatment, particularly treatment aimed at changing the position of teeth, the teeth may continue to shift. They tend to revert to a position prior to the orthodontic treatment, or even evolve into a new, unexpected position that can cause abnormalities.

[0009] By dentition, we mean all the teeth of a person, dentition corresponding to the dynamic process of tooth formation (of the dentition).

[0010] Orthodontic retention aims to maintain the alignment of the teeth acquired after orthodontic treatment, that is, to keep the teeth in place. Such retention can be permanent or last until the bone surrounding the tooth roots stabilizes the teeth in a new position.

[0011] Several methods of orthodontic retention are known, primarily retention splints and retention wires.

[0012] Retainers are devices designed to surround, protect, and support the entire dentition, usually made of clear plastic. A retainer can, for example, be shaped like a negative of the dentition obtained after orthodontic treatment. The retainer is therefore a heavy and restrictive device for the patient. Furthermore, as mentioned previously, since retention techniques are designed for the long term, even lifelong use, it is important to ensure that the patient continues to wear the retainer. The use of retainers is thus limited, as they are too cumbersome.

[0013] Another solution, used in conjunction with or as a replacement for retainers, is the retention wire.

[0014] A retainer wire is a metal alloy wire bonded to the lingual surface of the teeth, that is, towards the inside of the teeth. It is usually placed at the end of orthodontic treatment and extends from one canine to the other, or even from one premolar to the other. These wires provide lighter retention and do not hold the teeth in place laterally, but are therefore much easier to wear.

[0015] To obtain the desired shape of the retention wire, it is known to cut the profile from a shape-memory material. Document EP 3934562 B1 discloses a retention wire made from a nickel-titanium alloy, which is obtained by metal milling. In other words, the retention wire profile is cut from a nickel-titanium plate.

[0016] The Applicant observes that such solutions result in a fragile and breakable retention wire. When the retention wire breaks, its retention effect is disrupted and it must be replaced as soon as possible.

[0017] The known solutions generally allow for the production of a solid, rectangular-section nickel-titanium wire. Such a wire also tends to break the adhesive bonds during tooth movement.

[0018] These solutions are therefore suitable for the lower part of the teeth, which are less mobile, but not for the upper part. Furthermore, placing retainers on the upper teeth is even more challenging because, when the mouth is closed, the lower teeth rest on the lingual surface of the upper teeth, and therefore risk colliding with the retainer wire.

[0019] It is also known to deform a wire, particularly a "straight" wire, to give it the desired shape. Some digital manufacturing solutions use a robot to bend the wire according to the required shape. Such a solution is only applicable to wires with plastic deformation, particularly steel wires, and preferably to wires with a round cross-section, as rectangular wires are more elastic and difficult to handle. The use of a round-section wire for wire bending presents additional limitations, notably less resistant adhesive bonds on the teeth.

[0020] It is also known to take advantage of shape-memory materials, particularly nickel-titanium alloys, to mold orthodontic wires into a precise shape. This practice has been known for a long time, especially since the 1980s.

[0021] Document JPS5850950A, published in 1983, discloses a manufacturing process for orthodontic wire, in which a mold is provided with a groove corresponding to the desired shape of the orthodontic wire. A nickel-titanium wire is placed in the groove and then heated to activate its shape memory. Once cooled, the orthodontic wire naturally returns to the shape imparted by the groove.

[0022] We can also cite document US2008254403, published in 2008, which discloses a method for manufacturing an orthodontic wire. In this method, a virtual model of the patient's dentition is created and distorted to determine a wire pattern configured to transmit the desired energy to the patient's teeth. Once the wire shape is determined, a support is milled to form a groove with the determined shape. An orthodontic wire, for example, a nickel-titanium wire with a round, square, or rectangular cross-section, or a multi-strand steel or cobalt-chromium wire, is placed in the support and heated.

[0023] However, it still appears that orthodontic wires obtained in this way remain too fragile.

[0024] The Applicant therefore submits that there is currently no satisfactory alternative solution for manufacturing support wire that allows for obtaining a wire of the desired shape and exhibiting good mechanical properties.

[0025] Summary of the invention

[0026] The present invention aims to improve the current situation described above. More particularly, the present invention aims to overcome the aforementioned drawbacks by providing a method and system for manufacturing a support wire that produces a robust wire with a shape suitable for support.

[0027] To this end, the object of the present invention relates in a first aspect to a method for manufacturing a retention wire, the retention wire having a folded shape following the lingual face of a denture, the method comprising the following steps:

[0028] - first obtaining a yarn made from a shape-memory material, the yarn having a rectangular cross-section comprising a plurality of braided strands;

[0029] - secondly, obtaining a mold comprising a groove defining the folded shape of the retaining wire;

[0030] - assembly of the wire in the groove;

[0031] - activation of the shape memory material of the wire in said groove.

[0032] It is understood here that, before the wire is placed in the groove and the shape memory is activated, the wire can have any initial shape, for example a straight shape.

[0033] The Applicant submits that the use of a wire with a rectangular cross-section comprising a plurality of braided strands greatly increases the mechanical resistance of the resulting restraint wire.

[0034] The use of shape-memory wires with a braided rectangular cross-section has long been known to those skilled in the art for the production of orthodontic wires. One such wire is described, for example, in US document 5080584A, published in 1992. This document simply describes winding a braided rectangular cross-section wire around an arched support before heating it to obtain an arched wire.

[0035] The Applicant submits that no technical solution has yet combined the use of braided rectangular-section wires with a method of activating the wire's shape memory by placing the wire in a groove of the desired shape, for the manufacture of a retention wire. This design thus makes it possible to obtain a retention wire whose shape corresponds exactly to the desired folded shape, while offering superior mechanical properties compared to conventional retention wires.

[0036] In particular, the increased strength of the wire allows it to adapt to the lingual surface of an upper or lower dentition. Naturally, the folded shape of the retention wire—that is, the final shape obtained after the shape memory is activated—corresponds to the desired shape for its use as a retention wire.

[0037] It is also understood that activation refers to a process, selected according to the shape-memory material, that activates the shape memory, meaning that the folded shape of the wire is recorded, so that the support wire naturally returns to its folded form. In other words, activating a shape-memory material is a change in the material's state that modifies its shape memory. Once the shape memory is modified while the wire is in its folded form, this folded form becomes the wire's "initial" state, to which the shape memory returns. Activation preferably involves heating the wire in the groove. Naturally, activation is followed by a return of the wire to its initial state, specifically a cooling process, so that the wire can be worn while retaining the shape memory associated with the folded form.

[0038] The Applicant further submits that the use of a braided rectangular section wire offers a plurality of advantages over a braided round section wire.

[0039] In particular, the rectangular shape allows for a superior bonding surface on the teeth.

[0040] Furthermore, braided round wires tend to unravel over time. A braided round wire can twist the wearer's teeth. Conversely, it is also possible for the tooth to gradually rotate around the round wire.

[0041] Thanks to the present invention, the manufacturing process makes it possible to obtain a retention wire with both a specific shape adapted to its use and superior mechanical properties, minimizing the risk of wire breakage without making it more bulky. The retention wire thus obtained is more resilient, easier to use, and suitable for retaining both lower and upper teeth.

[0042] In an advantageous embodiment of the present invention, the shape memory material corresponds to a nickel-titanium alloy.

[0043] Those skilled in the art understand that nickel-titanium, also known as Nitinol, is commonly used in the manufacture of shape-memory orthodontic wires. This material can be activated by heating and retains its shape memory once placed on the teeth. In an additional embodiment, the folded shape has a lateral face intended to be in contact with the teeth, this lateral face extending obliquely with respect to a vertical axis.

[0044] It is understood here that the concepts of horizontal and vertical are understood in reference to the position of a retention wire within the dentition. The dentition, whether upper or lower, extends approximately in a horizontal plane corresponding to a reference position of the dentition of a person in a normal standing position, as does the bent shape of the wire. The teeth and the lateral face of the retention wire extend from this horizontal plane. The Applicant submits that the lingual face of the dentition does not extend directly vertically, but rather obliquely, that is, at an angle to a vertical axis perpendicular to the horizontal plane. Providing an oblique lateral face thus allows the retention wire to better conform to the dentition, and therefore increases the contact surface between the retention wire and the teeth, particularly the surface area for applying adhesive.The oblique orientation corresponds to the same oblique orientation of the teeth to which the retention wire is to be bonded. The lateral surface is therefore oblique, like an orthodontic torque, as understood by a professional. This torque, that is, the oblique orientation of the lateral surface and / or the retention wire, can be adapted to each tooth in the dentition, meaning it can be progressively changed along the retention wire so as to vary between each tooth.

[0045] It is further understood that providing an oblique lateral face preferably corresponds to providing a groove whose shape is a negative of the oblique face. The groove may, for example, have a parallelepiped cross-section, in which the lateral face (and, for example, its opposite face) is oblique and the top and bottom faces extend in a horizontal plane, or a rectangular cross-section, which is offset by a given angle so as to present the oblique face while maintaining the same cross-section.

[0046] In an additional embodiment, the second method comprises the following steps:

[0047] - third obtaining a representative data point of the folded shape;

[0048] - engraving the groove in the mold according to the given bent shape. It is understood here that the mold is made, during the execution of the process, in a specific way with respect to the desired bent shape.

[0049] The mold corresponds, for example, to a plate made of conductive material, for example a metal plate, preferably aluminum.

[0050] Preferably, the third step involves the following:

[0051] - fourth obtaining a representative data point of the dentition;

[0052] - drawing of the folded shape according to the toothing data.

[0053] In other words, the folded shape of the retainer wire is specifically determined according to the dentition for which the retainer wire is intended. It is understood here that the folded shape is designed to follow, directly or indirectly, the lingual surface of the dentition.

[0054] The representative data of the teeth is obtained, for example, by scanning the teeth and taking a cross-section along a substantially horizontal plane, corresponding to the plane along which the retaining wire is intended to be placed. Alternatively, the representative data of the teeth, or the representative data of the folded shape as described above, is received by communication with means external to the execution of the process.

[0055] Depending on the design, the folded shape is drawn in a fully automated way by computer means, for example the processor as described below, or drawn in a computer-assisted way.

[0056] In a specific embodiment, the folded form has a first set of contact portions, each contact portion corresponding respectively to a tooth of the dentition, and a second set of interdental portions, each interdental portion being arranged between two contact portions and having a curved shape without sharp angles.

[0057] In other words, the folded shape follows the lingual surface of the dentition at each tooth, specifically at a central portion of each tooth. Between teeth, that is, in the interdental spaces, the folded shape does not follow the dentition but instead has a curved shape that allows it to reach the next contact point. This design ensures that the retainer wire has no sharp edges and is less brittle. The detachment of the retainer wire at each interdental space also facilitates cleaning the teeth when the retainer is worn. In another embodiment, the rectangular section has a height and a width, with the height being greater than the width. The wire is assembled in the groove along its shorter side, so that the retainer wire has a height greater than the width of the retainer wire.

[0058] It is understood here that, in accordance with the notions of vertical and horizontal defined above, the width of the retainer wire corresponds to the thickness according to which the retainer wire extends in the plane of the dentition, that is to say in a substantially horizontal plane, and the height of the retainer wire corresponds to the dimension according to which the retainer wire extends so as to follow the height of the teeth, that is to say in a substantially vertical or oblique manner with respect to the vertical as defined above.

[0059] Of course, the concepts of height and width of the rectangular section of the wire before it is placed in the groove can be used interchangeably, as the initial wire has no predefined orientation. Conversely, once the retention wire has been folded, it has a specific orientation for its association with a tooth.

[0060] The Applicant submits that retention wires are usually wider than they are tall. Providing a retention wire that is taller than it is wide allows, for the same mechanical properties, for maximum contact area with the tooth and therefore the surface area for the adhesive to adhere to the wire. Furthermore, an excessively wide retention wire can impede tongue movement while wearing it.

[0061] A person skilled in the art also understands that a restraint wire with a height greater than its width has increased vertical resistance, that is, greater resistance to forces applied according to the height of the wire.

[0062] In another embodiment, the rectangular section has a height and a width, the width being greater than the height, the wire being assembled in the groove along its longest side so that the restraint wire has a width greater than a height of the restraint wire.

[0063] Conversely, a retention wire that is wider than it is tall exhibits increased transverse resistance, meaning it offers greater resistance to forces applied along the wire's width. Furthermore, an excessively tall retention wire can collide with the other half of the dentition, particularly the lower teeth when the wire is worn on the upper teeth.

[0064] According to another variant, it is also possible that the wire has a square section, that is to say a rectangular section whose height and width are equal or substantially equal.

[0065] In one embodiment, the process further includes a surface treatment step of the wire, by adding at least one material, so as to alter the external appearance of the wire.

[0066] Preferably, the surface treatment step involves rhodium plating. This treatment alters the appearance of the retainer wire, making it more discreet when worn. Naturally, the selected material must not negatively affect the mechanical properties of the resulting retainer wire, nor exhibit any toxicity that would impact its wear.

[0067] In another embodiment that can be combined with the previous embodiments, the mold is made of a thermally conductive material, the activation corresponding to a uniform heating of the mold.

[0068] It is understood here that the shape-memory material is activated by heating the wire within the groove. Specifically, the uniform heating of the thermally conductive mold ensures even heating of the wire and prevents any deformation resulting from heating, both in the mold and the wire. Thus, this design ensures that the resulting retaining wire conforms precisely to the folded shape defined by the groove.

[0069] In one embodiment, the process is implemented by at least one processor.

[0070] Here we understand that, in this design, the process is implemented by computer means, the processor controlling for example an automaton configured to assemble the wire in the mold and activate the shape memory material, notably by heating the mold.

[0071] Optionally, the processor is configured to control the engraving of the groove in the mold based on the bent shape data, or even to automatically draw the bent shape from representative data of the gear teeth, in accordance with the embodiments described above. According to a second aspect, the present invention relates to a computer program comprising instructions for implementing the steps of the process according to the first aspect of the present invention, particularly when these instructions are executed by a processor.

[0072] According to a third aspect, the present invention relates to a computer-readable recording medium on which is recorded a computer program comprising instructions for carrying out the steps of the process according to the second aspect of the present invention.

[0073] On the one hand, the recording medium can be any entity or device capable of storing the program. For example, the medium can include a storage means, such as a ROM, a CD-ROM or a microelectronic circuit-type ROM, or a magnetic recording means or a hard drive.

[0074] On the other hand, this recording medium can also be a transmissible medium such as an electrical or optical signal, such a signal being able to be transmitted via an electrical or optical cable, by conventional or radio frequency, by self-directing laser beam, or by other means. The computer program according to the present invention can, in particular, be downloaded from a network such as the Internet.

[0075] Alternatively, the recording medium may be an integrated circuit in which the computer program is incorporated, the integrated circuit being adapted to execute or to be used in the execution of the process in question.

[0076] According to a fourth aspect, the present invention relates to a system for manufacturing a retention wire, the retention wire having a shape folded to follow the lingual surface of a denture, the system comprising:

[0077] - means for assembling a wire made of a shape-memory material, the wire having a rectangular cross-section comprising a plurality of braided strands, with a mold comprising a groove defining the folded shape of the retaining wire, the wire being assembled in the groove; and

[0078] - means for activating the shape memory material of the wire in the groove. It is understood here that the activation means preferably correspond, depending on the shape memory material, to means for heating the wire in the groove so as to activate the shape memory material.

[0079] Preferably, the system includes means configured for implementing the steps of the process according to the first aspect of the present invention.

[0080] The system advantageously includes computer means comprising a processor configured for the implementation of the steps of the process according to the first aspect of the present invention.

[0081] According to a fifth aspect, the present invention relates to a restraint wire that can be obtained by the process according to the first aspect of the present invention.

[0082] Thus, through the various functional and structural technical characteristics above, the Applicant proposes a process and a manufacturing system for a support wire that allows obtaining a support wire of the desired shape and exhibiting superior mechanical properties to common support wires.

[0083] Description of the figures

[0084] Other features and advantages of the present invention will become apparent from the description of the specific and non-limiting embodiments of the present invention below, with reference to the attached Figures 1 to 6, in which:

[0085] [Fig.1] - Figure 1 schematically illustrates a top view of a tooth equipped with a retaining wire according to a first particular and non-limiting embodiment of the present invention;

[0086] [Fig.2] - Figure 2 schematically illustrates a perspective view of a denture equipped with a retainer wire conforming to figure 1;

[0087] [Fig.3] - Figure 3 schematically illustrates a front view of a denture equipped with a retainer wire conforming to figure 1;

[0088] [Fig.4] - Figure 4 illustrates a lateral section of a tooth equipped with a retainer wire conforming to Figure 1; [Fig.5] - Figure 5 illustrates a cross-section of a tooth for the design of a retainer wire conforming to Figure 1;

[0089] [Fig.6] - Figure 6 illustrates a lateral section of a denture equipped with a retention wire exhibiting an orthodontic torque according to a second particular and non-limiting embodiment of the present invention;

[0090] [Fig.7] - Figure 7 schematically illustrates a processor configured to implement a manufacturing process for a restraint wire conforming to Figure 1 and / or 6;

[0091] [Fig.8] - Figure 8 illustrates a flowchart of the different stages of a manufacturing process for a restraint wire conforming to Figure 1 and / or 6.

[0092] Detailed description

[0093] A process and a system for manufacturing a retainer wire, as well as a retainer wire obtained via such a process and / or system, will now be described in what follows with joint reference to Figures 1 to 8. The same elements are identified with the same reference symbols throughout the description that follows.

[0094] As stated in the preamble to the description, the currently offered retention wires are liable to break or come loose during their use, which necessitates replacement of the wire otherwise dental problems may reappear.

[0095] One of the objectives of the present invention is to propose a method and a system for manufacturing a retention wire that allows for obtaining a robust retention wire adapted to the dentition of each patient.

[0096] This is made possible in the following example.

[0097] As illustrated in figures 1 to 6, the example described here provides a system and method for manufacturing a retainer wire 11 adapted to a dentition 12, in which the retainer wire 11 follows an upper dentition, from canine to canine.

[0098] It will be understood here that this example is not limiting and that the invention will find other applications for the manufacture of retention wires adapted to lower dentition, as well as retention wires of different lengths, particularly those extending from one premolar to the other. More generally, the retention wire can be adapted to any portion of an arch or to a complete arch, whether medially or medially, and associated with lower or upper dentition. In accordance with the principle of a retention wire, the retention wire 11 follows the lingual surface of the dentition 12; that is to say, it is configured to be positioned along an medially oriented portion of the dentition 12.

[0099] Advantageously, the system includes computer means configured to implement the process of manufacturing the retainer wire, for example process 30 of figure 8. Such a manufacturing process is part of another larger process, for example in accordance with the variants of obtaining the mold as described below and / or a process including steps prior to the first obtaining for the preliminary realization of the wire and / or a process including subsequent steps once the retainer wire has been made, for example steps of placing the retainer wire on a tooth.

[0100] As illustrated in Figure 7, such computing resources are, for example, grouped into one or more electronic devices 20, such as a processor, a microprocessor, or a microcontroller. The elements of the device 20, individually or in combination, can be integrated into a single integrated circuit, into several integrated circuits, and / or into discrete components. The device 20 can be implemented in the form of electronic circuits and software (or computer) modules, or a combination of electronic circuits and software modules.

[0101] The device 20 comprises one (or more) processor(s) configured to execute instructions for carrying out the steps of the process and / or for executing instructions from the software embedded in the device 20. The processor may include integrated memory, an input / output interface, and various circuits known to those skilled in the art. The device 20 further comprises at least one memory 200, corresponding, for example, to volatile and / or non-volatile memory, and / or includes a memory storage device that may include volatile and / or non-volatile memory, such as EEPROM, ROM, PROM, RAM, DRAM, SRAM, flash, magnetic disk, or optical disk.

[0102] The computer code of the embedded software(s) including the instructions to be loaded and executed by the processor is for example stored on memory 200 of device 20.

[0103] In a first step 31 of the manufacturing process for the retention wire 11, the manufacturing system produces a wire made of a shape-memory material. The shape-memory material advantageously corresponds to a nickel-titanium alloy, which is commonly used for the manufacture of orthodontic wires. In particular, the wire has a rectangular cross-section comprising a plurality of braided strands. The wire is produced, for example, by braiding a plurality of individual strands and then deforming them into a rectangular cross-section, notably as described in US document 5080584A. The wire may comprise a greater or lesser number of individual strands, for example, 8 to 10 strands, each individually having a circular cross-section.It is understood here that the first step 31 may include such steps of forming the rectangular section wire from individual strands, or may correspond to a direct provision of a braided rectangular section wire, for example obtained by another process external to the system.

[0104] In a second step 32, the manufacturing system obtains a mold comprising a groove. The groove defines the folded shape of the retention wire 11; that is, it forms a negative of the shape of the retention wire 11. The groove thus corresponds to a negative of the shape of the retention wire 11 as illustrated in Figures 1 to 6. Therefore, when the wire is inserted into the groove, as described below, the groove imposes the desired shape of the retention wire 11 on the wire. The groove is thus defined according to the desired folded shape, and by extension, according to the denture 12 associated with the retention wire 11. In other words, the shape of the groove corresponds to the shape that allows the retention wire 11 to present a folded shape along the lingual surface of the denture 12.

[0105] As illustrated in figures 1 to 6, the teeth 12 extend along a substantially horizontal plane, and comprise a plurality of teeth 121 (figures 1 and 2) extending from the plane in a substantially vertical manner.

[0106] Advantageously, the folded shape has a first set of contact portions 112, such that each contact portion 112 corresponds to a tooth 121. In other words, for each tooth 121 of the dentition 12, a contact portion 112 of the retention wire 11 is provided such that a section of the retention wire 12 corresponds to the tooth 121 and can be brought into contact with it. Each contact portion 112 thus substantially follows the profile of the associated tooth 121. Between each contact portion 112, a second set of interdental portions 113 is provided. Each interdental portion 113 advantageously has a curved shape without sharp angles. In other words, these interdental portions 113 are not designed to be in contact with a tooth 121 and to follow its profile, such a design resulting in sharp angles between two teeth 121, but to connect the contact portions 112 together in a robust and flexible manner.It is understood here that, since the retention wire 11 has a rectangular cross-section and a folded shape that at least partially follows the teeth 121 of the dentition 12, and since the retention wire 11 is intended to be in contact with the dentition 12, this retention wire 11 has a portion explicitly dedicated to this contact. As illustrated in Figure 4, the retention wire 11 thus has a lateral face 111, defined by its rectangular cross-section. In this example, the lateral face 111 extends substantially vertically, and the retention wire 11 has a superior face 114 and a inferior face extending substantially horizontally, in planes parallel to the plane defined by the dentition 12, and also parallel to the plane in which the folded shape extends.It appears that, according to the lingual face of the dentition 12, the teeth 121 extend obliquely with respect to the vertical, that is to say obliquely with respect to an axis orthogonal to the plane of the dentition. 12.

[0107] Thus, according to the example in Figure 6, it is advantageous to ensure that the lateral face 111 also extends obliquely with respect to the vertical. In this same example, the retainer wire 11 has a superior face 114 and a inferior face extending obliquely with respect to the horizontal, defined as an axis parallel to the plane in which the folded shape extends, and a lateral face 111 extending obliquely with respect to a vertical defined as an axis perpendicular to this plane. In other words, the lateral face 111 extends so as to follow the orientation of the lingual face of the teeth 121 of the dentition 12, and the retainer wire 11 exhibits orthodontic torque.

[0108] As stated above, the second obtaining 32 corresponds to obtaining a mold whose groove defines the folded shape.

[0109] Advantageously, this second obtaining 32 includes a third obtaining 321 of a data representative of the folded shape.

[0110] In a first example, the device 200 receives this folded shape data via communication with a remote device, for example, another device dedicated to modeling the folded shape. The device 200 includes, for example, as illustrated in Figure 7, a beacon unit 201 configured to receive the folded shape data. The beacon unit 201 is configured, for example, to communicate wirelessly or via a wired connection, for example, using one or more of the following technologies: Wi-Fi, Bluetooth, BLE, or LTE. In particular, the folded shape is, for example, drawn manually by a specialist, notably from tooth data as described below, or from any representation allowing visualization of the teeth 12 and the tracing of the retaining wire 11.

[0111] According to a second example, the third acquisition 321 includes a fourth acquisition 3211 of data representing the teeth 12. The device 200, preferably the beacon unit 201, thus receives the teeth 12 data. The beacon unit 201 is, for example, in communication with a scanner 211 configured to return a representative image of the teeth 12, and / or with a database 212 configured to store a plurality of teeth data. Of course, it is also possible for the beacon unit 201 to receive the teeth 12 data prior to the other steps of the process, in which case it is stored in the device's memory 200.

[0112] Based on the tooth profile data, the device 200 creates a drawing 3212 of the folded shape, thus obtaining the folded shape data. The device 200 includes, for example, a calculation unit 202 configured to draw the folded shape. It is understood that such a design corresponds to the implementation of an automatic drawing of the shape of the retainer wire 11, or of the groove shape as the negative of the retainer wire 11. The drawing 3212 includes, for example, a cross-section of a representative image of the teeth 12, so as to draw the outline of the retainer wire 11 on the plane defined by this cross-section. Figure 5 illustrates such a cross-section. The retainer wire 11 therefore extends from the cutting plane, following the profile of the teeth 121 as they extend from the cutting plane.

[0113] Once the gear tooth data is obtained, the manufacturing system performs a groove engraving (322) in the mold. The mold initially corresponds, for example, to a blank plate, such as a plate made of a thermally conductive material; the manufacturing system then engraves the groove into the mold. Clearly, this design also includes a step of obtaining a blank mold.

[0114] The manufacturing system includes, for example, engraving means 213, and the device 200 includes a control circuit 203 configured to control the engraving means 213 according to the bent shape data.

[0115] This variant thus corresponds to the provision, by the manufacturing system, of a mold with a groove defining the folded shape from a blank mold. It is understood that it is also possible to design a process in which obtaining the mold with a groove is direct, the mold manufacturing then being separate from the operation of the manufacturing system and the execution of the process.

[0116] In a third step 33, the manufacturing system assembles the wire in the groove. The manufacturing system includes, for example, assembly means 214 configured to manipulate the wire and / or the mold so as to guide the wire into the groove, or to temporarily deform the wire to allow its placement in the groove. The device 200, for example the control circuit 203, thus controls the assembly means 214, notably according to instructions from memory 200 and / or according to data representing the respective shapes of the wire and the groove, for example according to the bent shape data.

[0117] As previously stated, the wire has a rectangular cross-section. This cross-section defines a height and a width, with the height being greater than the width. Of course, before the wire is bent into its final shape, its orientation can be adjusted so that the height and width are reversed.

[0118] Advantageously, the wire is assembled in the groove along its shorter side, which is its width. Thus, when the wire has the folded shape of the retainer wire 11, the height of the retainer wire 11, that is, its dimension along the lateral face 111, is greater than the width of the retainer wire 11, that is, its dimension along the upper face 114. It is further understood that this constraint on the wire assembly also corresponds to a constraint on the shape of the groove, so that the wire is inserted into the groove in a particular orientation that allows the folded shape to be obtained. The groove, for example, also has a height greater than its width relative to the plane in which the folded shape extends. Thus, the greater height of the retainer wire 11 maximizes the surface area on which the retainer wire 11 is bonded to the denture.

[0119] In a fourth step 34, the manufacturing system activates the shape-memory material in the groove. The manufacturing system includes, for example, activation means 215 configured for activating the shape-memory material. The device 200, for example the control circuit 203, thus controls the activation means 215, in particular according to instructions from memory 200 and / or according to data representative of the shape-memory material stored in memory 200, for example a specific activation temperature of the material. As stated above, the activation 34 corresponds, for example, to heating the wire. Such heating can be carried out using means known to those skilled in the art, in particular known for activating nickel-titanium orthodontic wires. The activation means 215 then correspond in this case to means for heating the wire in the groove.

[0120] Advantageously, activation 34 corresponds more precisely to a uniform heating of the mold, which is made of a thermally conductive material. The mold could be, for example, a metal plate. Uniform heating ensures consistent mold behavior under heat, and by extension, consistent wire behavior. Thus, this design ensures that the wire correctly adopts the bent shape corresponding to the shape of the mold groove.

[0121] Once the shape-memory material is activated, the wire adopts the folded shape over the long term, resulting in the desired retention wire 11. Activation 34 can therefore be stopped in any appropriate manner, in particular by stopping the stimulus associated with the activation, for example by cooling the retention wire 11.

[0122] Optionally, the manufacturing system implements a fifth surface treatment step 35 for the yarn, for example after its activation. Surface treatment 35 involves adding a material to alter its external appearance. In particular, such a surface treatment 35 corresponds, for example, to rhodium plating, making it possible to obtain a more discreet-looking support yarn 11 without altering its properties.

[0123] Thus, it will be understood that the present invention provides a method and system for manufacturing a support wire combining a more robust wire with a series of steps enabling the production of a precisely shaped wire adapted to the function of a support wire. Such an invention therefore facilitates the use and wearing of support wires, limiting the risk of wire breakage and all associated discomfort. The present invention also provides a support wire that can be obtained by such a method and / or system.

[0124] It should be noted that this detailed description relates to a particular embodiment of the present invention, but in no way does this description limit the scope of the invention; on the contrary, its purpose is to remove any possible inaccuracy or misinterpretation of the following claims.

[0125] It should also be noted that the reference signs placed in parentheses in the following claims are in no way intended to be limiting; these signs are solely intended to improve the intelligibility and understanding of the following claims and the scope of the protection sought.

Claims

Demands 1. Method for manufacturing a retention wire (11), said retention wire (11) having a folded shape following the lingual face of a denture (12), said method comprising the following steps: - first obtaining (31) of a yarn made of a shape memory material, said yarn having a rectangular cross-section comprising a plurality of braided strands; - second obtaining (32) of a mold comprising a groove defining said folded shape of said retaining wire (11); - assembly (33) of said wire in said groove; - activation (34) of said shape memory material of said wire in said groove.

2. A method according to claim 1, wherein said shape memory material corresponds to a nickel-titanium alloy.

3. Method according to claim 1 or 2, wherein said folded form has a lateral face (111) intended to be brought into contact with said toothing (12), said lateral face (111) extending obliquely with respect to a vertical axis.

4. A method according to any one of claims 1 to 3, wherein said second production (32) comprises the following steps: - third obtaining (321) of a data representative of said folded shape; - engraving (322) of said groove in said mold according to said folded shape data.

5. A process according to claim 4, wherein said third obtaining (321) comprises the following steps: - fourth obtaining (3211) of a data representative of said dentition (12); - drawing (3212) of said folded shape according to said toothing data.

6. A method according to any one of claims 1 to 5, wherein said folded form has a first set of contact portions (112), each contact portion (112) corresponding respectively to a tooth (121) of said toothing (12), and a second set of interdental portions (113), each interdental portion (113) being disposed between two contact portions (112) and having a curved shape without sharp angles.

7. A method according to any one of claims 1 to 6, wherein said rectangular section has a height and a width, said height being greater than said width, said wire being assembled in said groove along its shorter side so that said restraint wire (11) has a height greater than a width of said restraint wire (11).

8. A method according to any one of claims 1 to 6, wherein said rectangular section has a height and a width, the width being greater than the height, said wire being assembled in said groove along its longest side so that said restraint wire (11) has a width greater than a height of said restraint wire (11).

9. A method according to any one of claims 1 to 8, further comprising a surface treatment step (35) of said wire, by adding at least one material, so as to alter the external appearance of said wire.

10. A method according to any one of claims 1 to 9, wherein said mold is made of a thermally conductive material, said activation (34) corresponding to a uniform heating of said mold.

11. A method according to any one of claims 1 to 10, said method being implemented by at least one processor.

12. Product computer program comprising instructions for carrying out the steps of the process according to any one of claims 1 to 10, when these instructions are executed by a processor.

13. Computer-readable recording medium on which a computer program according to claim 12 is recorded.

14. System for manufacturing a retention wire (11), said retention wire (11) having a folded shape following the lingual face of a denture (12), said system comprising: - means for assembling (214) a wire made of a shape-memory material, said wire having a rectangular cross-section comprising a plurality of braided strands, with a mold comprising a groove defining said folded shape of said retaining wire, said wire being assembled in said groove; and - means for activating said shape memory material of said wire in said groove.

15. Restraint wire made of a shape-memory material, said restraint wire having a rectangular cross-section comprising a plurality of braided strands, said restraint wire having a folded shape capable of being obtained by the process according to any one of claims 1 to 11.

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