EP2670341A1

EP2670341A1 - Tubular dental reinforcement preform for forming a dental retaining band

Info

Publication number: EP2670341A1
Application number: EP12708559.5A
Authority: EP
Inventors: Bruno CLUNET COSTE; Bernard Maneuf; André Collombin
Original assignee: Bio Composants Medicaux (BCM)
Current assignee: Bio Composants Medicaux (BCM)
Priority date: 2011-02-02
Filing date: 2012-01-31
Publication date: 2013-12-11
Also published as: WO2012104504A1; US20130309627A1; CA2826370A1

Abstract

The invention relates to a tubular dental reinforcement preform formed by a cord made from woven fibres. The cord is impregnated and filled by a polymerizable resin and is able, by isostatic crushing, to take the shape of a strip without breaking of the woven fibres constituting the cord, the polymerizable resin being able to creep through the cord to form two lateral parts. The invention also relates to a production method of a dental contention strip from such a tubular reinforcement preform.

Description

TUBULAR DENTAL REINFORCEMENT FOR FORMING A DENTAL CONTENT BAND

TECHNICAL FIELD OF THE INVENTION The invention relates to a tubular dental reinforcement preform formed by a braided fiber rope.

State of the art

Reinforcing means are used in the manufacture of dental splints or tapes. Known dental splints may consist of wire or metal wicks. The disadvantage of metal splints remains their unsightly appearance, rigidity and the fact that they must be embedded in resins to improve the appearance.

US-A-2755552 discloses fiber reinforcements for reinforcing dental prostheses, crowns or making invisible and colorless splints.

The document FR-A-2588181 discloses the use of fibers made of composite materials for reinforcing dental prostheses based on totally or partially polymerized resins, produced by pultrusion, injection, compression, molding, or transfer. The resin is in a partially polymerized form and may be epoxy resin, polyester or any other resin provided it is compatible with the fibers used. The fibers may be of any kind, glass, ceramic, boron, boron carbide, silicon carbide, synthetic fibers, in the form of bundles of fibers, parallel, optionally covered, fabrics, knits or braids. Each type of fiber has indications and disadvantages:

- Parallel fibers are used in areas subject to heavy loads but are more rigid and difficult to work.

- Wicks, cords and braids circular section or oval 1 mm or 2 mm are easier to handle due to weaving. They have little memory shape but they have the disadvantage of occupying more space and can interfere in the occlusion.

- Ribbons have the advantage of being flat and occupy little occlusal space, but they are more rigid and have a strong memory shape.

US-A-4717341 and US-A-4894012 describe reinforcing elements that can be used as active or passive elements in orthodontics and dental prostheses. These elements are in the form of elongated elements and allow in particular to secure the teeth together. These elements are generally proposed in the pre-polymerization state and consist of a photopolymerizable resin. We speak of "prepregs" or "prepeg".

As shown in FIG. 1, a dental compression band 1 is bonded to the dental surfaces 2 by means of a photopolymerizable composite adhesive by various known means. A spatula (not shown) is generally used to hold the element on the dental surface 2. The dental compression tape 1 and the adhesive are insulated to polymerize the photopolymerizable composites and harden the assembly. Sunstroke is performed step by step, progressing from one tooth to another tooth.

As shown in FIG. 2, another technique consists in maintaining the dental compression band 1 on the dental surfaces 2 by means of a strip 3 transparent to light rays. The strip 3 may be applied by mechanical means, suture threads, forceps, or by means of a preformed transparent gutter prepared in the laboratory according to any known method.

The means of the state of the art for applying to the dental surfaces a dental compression band are difficult and time consuming to implement. The application with a spatula or a strip held by mechanical means, spatulas, hooks, gutters, son, is difficult in a context where the dental surfaces must remain free of moisture. This results in gaps and a lack of cooptation of the splint on dental surfaces that can compromise the durability of the system.

In addition, during step insolation, the light initiates the polymerization of a length of compression band greater than the portion in contact with the target tooth surface, and the application of the partially cured band becomes difficult on the next tooth.

US-A-5921778 discloses the use of woven yarns embedded in a polymer matrix for application to teeth. This embodiment requires on the one hand to form the matrix at the teeth and secondly to fix the woven son on the matrix.

The known means of the state of the art do not allow to apply a compression band on a complex surface by applying a uniformly distributed pressure over its entire surface and even less by uniformly varying the section of the band of contention. Object of the invention

The invention aims to avoid the disadvantages of the prior art and in particular to facilitate the installation of a dental compression band. This object is achieved by the appended claims and in particular in that the reinforcing preform is formed by a braided fiber cord, the cord is impregnated and filled with a polymerizable resin and is adapted to adopt, by isostatic crushing, a ribbon shape without breaking the braided fibers constituting the cord, the polymerizable resin being able to flow through the cord when the latter is subjected to isostatic crushing.

Another object of the invention is to provide a method for shaping the initially tubular reinforcing preform to form a dental compression band, by exerting an isostatic pressure on said preform, the application of the pressure simultaneously allowing crushing the initially tubular string ribbon and expel the polymerizable resin out of the tubular string to form the two side portions on either side of the ribbon, and then polymerize the polymerizable resin.

Another object of the invention is to obtain a dental compression band made of a composite material based on a polymer material and reinforcing means formed by a braided fiber cord, said compression band being formed by a central part, comprising the reinforcing means, located between two lateral parts consisting solely of the polymeric material, said reinforcement means being embedded in the polymeric material, the compression band having a thickness less than or equal to 0.7 mm, said lateral portions representing at least 8 % of the total mass of said compression band, and said fiber cord being flattened in the form of a ribbon. Another object of the invention relates to the use of a hand-held instrument with a preform for the application of a dental compression element, said instrument comprising:

a gripping member provided with a reservoir receiving the dental reinforcement preform in the pre-impregnated state before polymerization,

means for applying and forming said preform, said preform having a first initial shape and being able to adopt, by crushing, a second form, in the form of a strip or ribbon, distinct from the first form,

the reservoir communicating with the application and forming means so as to dispense said preform continuously, and the application and forming means being shaped so as to apply said preform while transforming it into its second form and the means application and forming comprising a tip opaque to light radiation, finished by an application head transparent to light radiation.

Brief description of the drawings

Other advantages and features will emerge more clearly from the following description of particular embodiments of the invention given by way of non-limiting example and represented in the accompanying drawings, in which:

Figures 1 and 2 show, schematically and in perspective, a dental compression tape according to the prior art, mounted on the dentition of an individual.

Figures 3 and 4 show schematically and respectively in perspective and in section, a compression band according to a particular embodiment of the invention. Figures 5 and 6 show schematically and, respectively, in perspective and in section, a reinforcing preform for obtaining a compression band according to Figures 3 and 4.

Figures 7 and 10 show, schematically and in section, different steps of a method of producing a compression band according to Figures 3 and 4.

Figure 11 shows schematically and in perspective, a hand instrument according to a particular embodiment of the invention.

FIG. 12 represents, schematically and in perspective, an enlargement of FIG.

FIG. 13 represents, schematically and in view from above, a step of a method of using an instrument according to a particular embodiment of the invention.

Figure 14 shows, schematically and in perspective, a hand instrument with preform according to a particular embodiment of the invention.

FIG. 15 represents, schematically and in perspective, an enlargement of FIG.

Description of particular embodiments.

According to a particular embodiment shown in FIGS. 3 and 4, a dental compression band 1 is formed by a composite material based on a polymer material 4 and reinforcing means 5.

The reinforcing means 5 are embedded in the polymer material 4.

The dental compression band 1 is formed by a central portion 6 between two lateral portions 7. The lateral portions 7 are adjacent to the central portion 6. In other words, preferably, the central portion 6 is located between the lateral portions. The central portion 6 comprises the reinforcing means 5. The reinforcing means 5 are formed by a braided fiber rope 8, flattened in the form of a ribbon or band. By braided fibers is meant that the fibers are woven or knitted.

The cord is preferably selected from the low-dimensional, woven or knitted cords. The cord is, for example, made of long fibers knitted or woven with a particular weave conferring a low shape memory.

By weak memory of form, one understands the inability to keep in memory an initial form and thus the incapacity to return to this initial form after a deformation.

Preferably, the long fibers constituting the cord are glassy siliceous artificial mineral fibers, known as glass, silica, quartz, ceramic, but they may also be polycrystalline vitreous artificial fibers such as for example alumina fibers and of alumina silicates. The cords may also consist of organic fibers such as polyolefins, polyamides or para-amides, polyethylene, polyurethanes or any other suitable polymer that would be chosen by those skilled in the art. Other so-called natural fibers may also be used, such as natural or modified plant or animal fibers.

The cord may, optionally, be partially filled with long unidirectional fibers 9 to improve the mechanical strength and crush resistance. The long unidirectional fibers 9 may be of the same nature or of a different nature from the braided fibers constituting the cord. These fibers can constitute a soul of the cord and represent a brake to the initial recovery of shape cord. In fact, the friction of the long fibers inside the cord prevents the cord which passes from an initial form to a second form to return to the initial shape spontaneously. The lateral parts 7 consist solely of the polymer material 4 and represent at least 8% of the total mass of said compression band 1. The 8% corresponds to the mass fraction of the polymer material 4 in the compression band 1. The polymer material 4 may comprise additives and / or dyes improving the mechanical and / or aesthetic properties of the compression band 1.

As shown in FIG. 4, the compression band 1 has an almost rectangular section. The compression band 1 described above has a thickness, advantageously less than or equal to 0.7 mm and has improved mechanical properties. In particular, the compression band 1 adheres intimately to the dental surfaces 2 of an individual, or a laboratory dental model, thanks, in particular, to the presence of the two side portions 7 free of fibers 8 and 9 bordering the central portion 6 of the compression band 1.

The central portion 6 provides the reinforcement necessary to exert a contention, or solidarization, effective, and advantageously resistant, the dentition of an individual.

The compression band 1 described above can advantageously be obtained from a tubular reinforcing preform 11 shown in FIGS. 5 and 6, according to a particular embodiment method.

According to one particular embodiment, a tubular dental reinforcing preform 11 is formed formed by a tubular cord 12, braided fibers 8, impregnated and filled with a polymerizable resin 13 to produce the dental compression band 1. The tubular string 12 is impregnated with a polymerizable resin 13 in the pre-polymerization state. The tubular cord 12 is advantageously filled with at least 38% by weight of polymerizable resin 13, the percentage being calculated with respect to the total mass of the tubular reinforcing preform 11 (ie the mass fraction).

The choice of a mass percentage of 38% advantageously makes it possible, after isostatic crushing of the cord, to obtain two lateral strips of polymer material representing 8% of the total mass of the compression band.

The polymerizable resin 13 may be doped with one or more additives 10 and / or dyes, to give it a consistency allowing it to flow without flowing through the fibers 8 of the tubular string 12 or take a particular shade.

The polymerizable resin has preferably a viscosity between 1 and 5 Pa.s June ¹⁰ ^to September 10 Pa.s at 20 ° C.

The resin constituting the fiber impregnation gel may be an organic resin of the methacrylic ester type, in particular it may be polymethyl methacrylate (PMMA), urethane dimethacrylate (UDMA), glycidyl methacrylate and bisphenol A (BISGMA). , n-ethylene dimethacrylate (N EDMA), ethyl methacrylate (EMA), triethylene glycol dimethacrylate (TEGMA), carboxylic acid modified dimethacrylate (TCB) or a mixture of these esters. But it can also be any organic resin chosen by those skilled in the art from organic resins compatible with the coating of the fibers and whose polymerization can be initiated advantageously by electromagnetic radiation. The polymerizable resin is preferably photopolymerizable because it is a readily controllable technology especially in the dental field. Subsequently, although we speak of photopolymerizable resin, the skilled person can use any type of polymerizable resin.

The tubular string 12 forming the preform is chosen from cords adapted to adopt a ribbon shape by isostatic crushing, without breaking the braided fibers 8 constituting the tubular string 12. In particular, the cord 12 is chosen from the low-shape cords, woven or knitted.

The tubular cord 12 must be able to adopt two different conformations or positions, respectively before and after shaping the tubular reinforcing preform 11; an initial tubular conformation and a flattened conformation in the form of a ribbon.

The cord 12 may optionally comprise a long unidirectional fiber core 9 to improve the mechanical strength, the crush resistance and promote the absence of shape memory. The long unidirectional fibers 9 may be of the same nature or of a different nature from the braided fibers constituting the cord. The volume of unidirectional long fibers is determined so as to leave sufficient photopolymerizable resin 13 in the tubular string 12 to crush the tubular string 12, the lateral portions 7 of the dental compression band 1.

In other words, the core is disposed in the tubular string 12, advantageously co-axially to the tube of the cord 12. The core is separated from the inner surface of the tube of the cord 12 by the photopolymerizable resin. The tubular reinforcing preform 11 is made according to any known method from a hollow cord or partially filled with long fibers 9, and photopolymerizable resin 13. In fact, in general, it can be said that the tubular string may comprise a tube, formed for example of woven or knitted fibers, that the internal space of this tube can be filled by the resin. Advantageously, the fiber core may be disposed inside the tube and oriented along the longitudinal axis of the tube. Furthermore, the polymerizable resin is able to flow through the cord when the latter is subjected to isostatic crushing. Flowing means that when pressure is applied to the string, the resin can flow through the string. According to a particular embodiment shown in FIGS. 7 to 11, a production method makes it possible to obtain the dental compression band 1 from the tubular reinforcing preform 11 described above.

Thus, the method comprises at least two successive steps: the shaping of the initially tubular reinforcing preform 11 by exerting an isostatic pressure on said preform 11, the application of the pressure simultaneously making it possible to crush the initially tubular string 12 under ribbon form and expel the polymerizable resin 13 out of the tubular string 12 to form the two side portions 7 on either side of the ribbon, then the polymerization of the polymerizable resin 13. In the case of a photopolymerizable resin the polymerization is carried out by insolation.

The production method may comprise, before forming the preform, the successive steps described below. As shown in FIGS. 7 and 8, a negative impression 14 of the compression band 1 is made by means of a matrix 15, preferably transparent to light in the case of a photopolymerizable resin for effecting the polymerization of the resin by insolation of the matrix 15, from a reproduction 16 of the compression band 1 held in a predetermined position on a laboratory dental model 17 of an individual.

The matrix 15 is constituted by a conformable and polymerizable material (advantageously photopolymerizable). The matrix 15 is preferably formed by a transparent, conformable and polymerizable plastic material. The matrix 15 is chosen from transparent plastic materials which adhere neither to resins, nor to waxes, nor to dental surfaces or laboratory plaster. The matrix 15 is chosen, advantageously, from vinyl polysiloxanes.

By way of example, a reproduction 16 of tackifying material of the shape, of the rectangular final section of the compression band 1, is applied to the surface of the dental laboratory model 17 so as to fix the position of the future splint on For example, for a tubular reinforcing preform 11 with a section of 0.8 mm, the reproduction 16 may have a quasi-rectangular section having a width and an indicative length, respectively, of 0.3 mm and 1, 6 mm. By tackifying material is meant a tacky material, adhering. The matrix 15 may, for example, be applied and maintained in the predetermined position, by means of an element holder 18, completely or partially, transparent to light radiation.

According to a particular embodiment represented in FIG. 7, the element-holder 18 comprises a first fixed branch 19 and a second branch 20 movable along the first fixed branch 19. The first and second branches, 19 and 20, are provided at their end, respectively, of the matrix 15 and a support 21.

As shown in FIG. 8, a slide 22 allows the translation movement of the second limb 20 (horizontal arrow in FIG. 7) so as to clamp the dental model 17 of the laboratory. The matrix 15, conformable and photopolymerizable, then marries the surface of the dental model 17 on which it is applied and prints the reproduction 16 so as to form the negative impression 14.

The position is determined according to the finite form expected on the individual's dentition. The reproduction 16 may be made, for example, from an analog of tackifying material according to any known method. Preferably, the tackifying material may be a wax, and it may advantageously be eliminated by simple traction without leaving a residue. The wax may be a polymerizable or photopolymerizable wax.

After having positioned / allowed to cure the reproduction 16, the element / reproduction holder assembly is removed (horizontal arrow in FIG. 8) and the reproduction 16 in tackifying material (for example in polymerized wax) is eliminated.

As shown in FIG. 9, after the step of producing the negative impression 14, the tubular reinforcing preform 11 described above is then housed in the negative impression 14 so that a portion of the preform The tubular reinforcing preform 11 is thus inserted into the cavity 14, optionally coated (or painted) with a resin of the same nature as the photopolymerizable resin 13. As shown in FIG. 10, the subsequent step is to apply the matrix 15 provided with the tubular reinforcing preform 11 to the dental laboratory model 17 in the predetermined position. The initially tubular reinforcing preform 11 is shaped by exerting isostatic pressure on the reinforcing preform 11. The isostatic pressure is advantageously exerted by means of the element holder 18 (see horizontal arrow in FIG. 10). As previously, the holder element 18 is inserted on the dental laboratory model 17 and the second limb 20 is slid transversely to allow the dental model 17 to be pressed between the support 21 and the matrix 15 provided with the reinforcing preform 11 tubular.

The application of the pressure simultaneously makes it possible to crush the cord 12 and to expel the photopolymerizable resin 13 out of the cord 12, to transform the initially tubular cord 12 into a ribbon and to form the two lateral portions 7 of the compression band 1 dental. To promote the expulsion of the photopolymerizable resin 13 without casting, the consistency of the photopolymerizable resin 13 is adjusted, for example, by the addition of additives well known to those skilled in the art.

For example, the additives may be primary plasticizers such as phthalates, adipates, sebacates, epoxidized oils, polyester plasticizers, phosphates, glycol and derivatives or secondary plasticizers such as fatty acid esters, chlorinated organic derivatives, acid derivatives toluene. It may also be fillers, granular or fibrous reinforcements of mineral, vegetable or synthetic origin, in the form of powders, fibers, filaments, leaves or small balls. According to another example, the additives may be granular fillers, wood flour, calcium carbonate powders, kaolin, clay, mica, slate, talc, silica, flour of diatoms, sulphates of barium and calcium, alumina and other metal oxide powders such as carbon blacks, colloidal graphite or it can be crushed waste of synthetic resins. For fibrous fillers, it may be cellulose fibers, such as hemp, jute, ramie, cotton, rayon, or it may be some synthetic fibers. Advantageously, they are siliceous fibers. Dyes and pigments can also be used to provide a particular hue or radio opacity. They can be of mineral origin, organic or mixed, soluble or insoluble in the resin.

The dyes and / or pigments soluble in the resin may be mono- azo or diazo compounds bearing -OH or -NH 2 groups, anthraquinone amines, nigrosine or indulin bases, etc.

The dyes and / or pigments insoluble in the resin are, for example, minerals such as metal salt oxides of titanium, lead, chromium, manganese, cobalt, cadmium, iron, etc.

The dyes and / or organic pigments are preferably azo and diazo copulated, some indanthrene dyes, etc.

The dyes and / or mixed pigments are, for example, colored salts of organic acids.

Thus, the element holder 18 forming means for applying the tubular reinforcing preform 11 makes it possible to transform the tubular cord 12, woven or knitted, having a circular or oval section into a ribbon of substantially rectangular section occupying a reduced occlusal space. . The tubular string 12 has a section whose largest dimension is typically a few millimeters. The ribbon thus formed has a thickness indicative of the order of 35% of the largest dimension of the section of the tubular cord 12 and an indicative width of about 180% of the largest dimension of the section of the cord. 12 tubular.

As shown in FIG. 10, the pressure exerted enables the photopolymerizable resin 13 to flow through the initially tubular cord 12 and to perfectly fit the surface of the dental laboratory model 17.

The photopolymerizable resin 13 has a viscosity such that the photopolymerizable resin 13 can both be extruded out of the cord 12, through the woven or knitted fibers, and at the same time not infiltrate into the interstices of the dental model.

The application of the isostatic pressure thus advantageously makes it possible, simultaneously, to transform the cord 12, initially tubular, into a ribbon and concomitantly to shape said cord on the dental model.

After application to a laboratory dental model 17, the tubular string 12 undergoes a spatial transformation to become a ribbon. The application of an isostatic force through the element holder 18 over the entire surface of the tubular cord 12 allows its transformation into a ribbon of indicative thickness of the order of 35% of the largest dimension of the section of the tubular cord 12.

This transformation is made possible by a particular weaving of the fibers 8 of the tubular string 12 allowing its crushing without breaking the fibers 8 and the expulsion from the tubular string 12 of a portion of the photopolymerizable resin 13, to form side portions 7 of the final compression band 1, free of fibers 8 and 9. As a first example, the tubular string 12 of 0.8 mm section will be transformed into a ribbon of generally rectangular section having a width and length indicative, respectively, of 0.3mm and 1, 6mm. The ribbon is lined with two strips consisting solely of light-curing resin 13, free of fibers 8 and 9, each having a length indicative of 0.4 mm and which will constitute the two lateral portions 7 of the final compression band 1. The length of the strips must be large enough to obtain an advantageous effect on the adhesion of the final compression band 1.

As a second example, the tubular string 12 of section 1, 5 mm will be transformed into a ribbon of generally rectangular section having a width and an indicative length, respectively, of 0.6 mm and 3.4 mm. The ribbon is lined with two strips consisting solely of photopolymerizable resin 13, free of fibers 8 and 9 each having a length indicative of 0.5 mm.

Thus, it is the conjunction of a particular weave of the tubular string 12, of a suitable consistency of the photopolymerizable resin 13 and of an isostatic force applied to the tubular string 12 of the preform 11 by the element holder 18 which allows the transformation of the tubular string 12 into a ribbon of indicative thickness of the order of 35% of the largest dimension of the section of the tubular string 12, bordered by two side portions without fibers 8 and 9 and constituted only photopolymerizable resin 13 and, optionally, additives 10.

The last step is to polymerize the photopolymerizable resin 13 by insolation of the matrix 15 according to any known method to form the compression tape 1. The photopolymerizable resin 13 is, for example, subjected to radiation provided by a light source (not shown) passing through the matrix 15. Insolation cures the resin photopolymerizable 13 which hardens in its final form. The strip 12 flattened in the form of a ribbon occupies the central portion 6 and the polymerized resin 13 forms the polymer material 4. The production method according to the invention implements an acceptable mass photopolymerization process of the tubular string 12 transformed ribbon while maintaining the final compression band 1 intimately adapted to the laboratory dental model 17, by means of an element-holder instrument made of a material transparent to light radiation.

The production method according to the invention makes it possible to produce a dental compression band 1 comprising reinforcing means 5 in the form of a ribbon occupying a restricted occlusal space from a tubular reinforcing preform 11 comprising a tubular string 12 displaying , before its implementation, a low form memory and easy to handle. In other words, after the polymerization step, it is possible to obtain a compression strip made of a composite material based on a polymer material 4 and reinforcing means 5 formed by a braided fiber rope 8, said strip of contention 1 being formed by a central portion 6, comprising the reinforcing means 5, located between two lateral portions 7 consisting solely of the polymer material 4, said reinforcing means 5 being embedded in the polymer material 4. According to a variant, the impression negative mentioned above, may have lateral and longitudinal dimensions greater than those of the final compression band that is desired. On the other hand, the depth of the impression will be calculated so as to equal the final thickness of the compression band. In this example, the viscosity of the polymer will be adapted to correctly delimit the lateral bands of the compression band. According to a particular embodiment, the reinforcing preform 11 described above can be put in place and converted into a dental compression band using a hand-held instrument. The hand instrument is advantageously used for the installation of the compression band, also called dental compression element 1 in the following description. It allows both the dispensing, the application and the forming of the reinforcing preform 11 intended to be polymerized once applied to the dental surfaces of an individual or dental laboratory model, to form the element of dental restraint 1.

According to a particular embodiment represented in FIGS. 3 and 4, the dental compression element 1 consists of fibers, resin and fillers in the state of before polymerization and photopolymerizable on a dental surface, including at the level of the spaces. interdental.

According to a particular embodiment represented in FIGS. 11 to 15, a hand-held instrument for the installation of a dental compression element 1 comprises a gripping member 111 provided with a reservoir 112 intended to receive the dental reinforcing preform 11 and application and forming means 114 of the reinforcing preform 11.

As shown in FIGS. 11 to 12, the reservoir 112 communicates with the application and forming means 114 so as to dispense the reinforcing preform 11 in a continuous manner. In particular, the gripping member 111 is formed by a hollow tube of the pen-applicator type, finished by the application and forming means 114. The internal cavity of the tube then forms the tank 112 in which the preform of Reinforcement 11. The reservoir 112 is advantageously connected to the application and forming means 114 via an orifice 115 (FIGS. 11 and 12).

The application and forming means 114 comprise an opaque tip 116 to light radiation, terminated by an application head 117 transparent to light radiation. The applicator head 117 protrudes from the opaque tip 116 to form an end of the handpiece.

The application and forming means 114 comprise a zone 118 (FIG. 11) intended to be in contact with the dental surfaces 2 (FIG. 13) during the placement of the dental compression element 1.

The application head 117 is constituted by a reversibly deformable material transparent to light radiation and inert to the materials constituting the preform 11 and / or the dental compression element 1. Inert means that the reversibly deformable material does not adhere and does not react chemically to the materials constituting the preform 11 and / or the dental compression element 1. Reversibly deformable means a material that deforms when subjected to a mechanical stress and returns to its original shape once the solicitation is removed.

The reversibly deformable material may advantageously be an elastomeric polymer. In particular, the reversibly deformable material is preferably selected from silicones, polyamides, preferably Nylon® type, and polyoxymethylene (denoted "POM").

The applicator head 117 has a first face 119 provided with an open half-groove 120. By half groove 120 open is meant a groove formed along the first face 119 to form a channel.

The dimensions of the open half-groove 120 are determined by the projected final shape of the dental compression element 1. The section of the half-groove 120 open in the application head 117 is calculated to obtain the flattening of the reinforcing preform 11 at the orifice outlet 115. The contact zone 118 is, at least partially, constituted by the first face 119 of the application head 117.

The opaque tip 116 has a bevelled face, adjacent the first face 119 of the application head 117 and constituting a part of the contact zone 118. The bevelled face forms an angle Θ with the first face 119. The angle Θ is chosen so as to optimize the contact between the contact zone 118 and the tooth surfaces 2. The angle Θ is defined in order to optimize the application of the hand instrument to the dental surfaces 2, in particular in order to allow the application on the hand-held instrument of a force necessary for the crushing of the reinforcing preform 11 and its printing in the form of the compression element 1. The angle Θ is preferably between 90 ° and 130 °. According to a preferred embodiment, the application head 117 advantageously comprises a second face 121 adjacent to the first face 119. The second face 121 forms with the first face 119 a convex dihedron at the end of the instrument. hand. The convex dihedron preferably has an angle θ 'which can vary between 20 ° and 150 °.

The half-groove 120 extends from the orifice 115 to the tip of the dihedron. The half-groove 120 is advantageously extended from the first face 119 to the second face 121 of the convex dihedral without discontinuity. The contact zone 118 is preferably constituted by the bevelled face of the opaque tip 116, the first face 119 and the second face 121.

As shown in FIGS. 5 and 6, the reinforcing preform 11 used for the hand-held instrument according to the invention has a first initial shape. The reinforcing preform 11 is adapted to adopt, by crushing, a second distinct form of the first form. The first initial shape (FIGS. 5 and 6) is, advantageously, a tubular shape and the second shape is a form of ribbon or band corresponding to the shape of the restraining element 1 (Figures 3 and 4).

The tubular cord 122 is advantageously adapted to adopt two different conformations or positions, respectively before and after shaping of the reinforcing preform 11 in its first form by the hand-held instrument. Advantageously, as suggested above, the cord may be of the type of the cord 12 of FIGS. 5 and 6. Thus, in its first form, the cord may have a tubular initial conformation (FIGS. 5 and 6) and, in its second form a flattened conformation in the form of a band or ribbon (FIGS. 3 and 4).

According to a particular embodiment shown in FIGS. 13 to 15, the reinforcing preform 111 used for the handpiece is intended to form the dental compression element 1 by application to the dental surfaces 2 of the dental reinforcing preform 11 while insolating the application and forming means 114 during the application.

The use of the hand-held instrument consists of loading the tubular reinforcing preform 11 into the reservoir 112 by pulling one of its ends out of the orifice 115 and by engaging it in the half-groove 120 at least of the first face 119 of the application head 117.

The handpiece may be single-use or rechargeable. In the latter case, the reservoir 112 and the application and forming means 114 constitute two removable parts of the instrument.

As shown in FIG. 13, the contact zone 118 is then applied to the dental surfaces 2 so as to crush the tubular reinforcement preform 11 between the tooth surfaces 2 and at least the first face 119 of the application head 117. The first face 119 of the application head 117 is at least partly in contact with the surfaces 2 to allow crushing of the tubular reinforcing preform 11.

The application and forming means 114 are shaped so as to apply the reinforcing preform 11 while transforming it into its second form.

As shown in FIG. 13, the reinforcing preform 11 is applied to the dental surfaces 2 and converted into a band or ribbon by moving the handpiece step by step from one tooth to the other.

As shown in FIG. 13, the half-groove 120 has, in particular, a rectangular or oval or rectangular section with rounded angles, to form a dental compression element 1 in the form of a band or ribbon.

The half-groove 120 has a rectangular section equal to 2/10 ± 20% of the original section of the reinforcing preform 11. The reinforcing preform 11 leaves the opaque tip 116 at the level of the application head 117 to walk in the half groove 120 and simultaneously be shaped.

The open half-groove 120 constitutes a negative impression of the reinforcing preform 11 in its second form and is shaped so as to enable the reinforcement preform 11 to be conveyed into the half-groove 120, from the orifice 115 to the end of the instrument

The half-groove 120 is preferably shaped so that the reinforcing preform 11 in its second form has, advantageously, an indicative thickness less than or equal to 0.7 mm. In particular, the surface of the section of the half-groove 120 is smaller than the surface of the section of the orifice 115 in order to crush the reinforcing preform 11 at the outlet of the reservoir 112 and to obtain the reinforcing preform 11 under its second form.

The orifice 115 has dimensions adjusted to the dimensions of the reinforcing preform 11 in the form of a strip or ribbon so as to easily extract the tubular reinforcing preform 11 from the reservoir 112 while maintaining it in a determined position allowing the crushing of the tubular reinforcement preform 11 between the tooth surfaces 2 and the contact zone 118.

The reservoir 112 may advantageously comprise a compartment (not shown) containing photopolymerizable adhesive in fluid communication with the orifice 115 so as to deliver the adhesive, to impregnate the reinforcing preform 11 before being introduced into the d Application and forming 114. The adhesive is intended to coat the dental surfaces 2 during the application of the dental compression element 1. The hand-held instrument thus intimately applies the reinforcing preform 11 to the dental surfaces 2 of an individual or laboratory model, to turn it into a band or ribbon having a central portion bordered by two side portions. The central part and the lateral parts form after insolation polymerization, respectively, the central portion 6 and the lateral portions 7 of the dental compression element 1.

As shown in FIGS. 14 and 15, the application of a pressure via the applicator head 117 simultaneously makes it possible to crush the tubular string 122 and to expel the photopolymerizable resin 13 (as represented in FIG. 6 ) out of the cord 122, to transform the cord 122 initially tubular in a ribbon and forming the two lateral portions 7 of the dental compression element 1. To promote the expulsion of the photopolymerizable resin 13 without casting, the consistency of the photopolymerizable resin 13 is adjusted, for example, by the addition of one or more additives 110 well known to those skilled in the art and referred to above. before.

Thus, the tubular string 122, woven or knitted, having a circular or oval section is transformed into a ribbon or band of substantially rectangular section occupying a reduced occlusal space. The tubular string 122 has a section whose largest dimension is conventionally a few millimeters.

The ribbon or strip thus formed has a thickness indicative of the order of 35% of the largest dimension of the section of the tubular string 122 and an indicative width of the order of 180% of the largest dimension of the section. of the tubular string 122.

As shown in FIGS. 14 and 15, the pressure exerted enables the photopolymerizable resin 13 to flow through the initially tubular cord 122 and to perfectly fit the dental surfaces 2 of either an individual or a dental laboratory model. .

After application to the dental surfaces 2, the indicative thickness of the tubular cord 122 is, advantageously, of the order of 35% of the largest dimension of the section of the tubular cord 122.

The polymerization can then be carried out as described above in the last step of polymerizing the photopolymerizable resin by insolation. In fact, the method remains substantially identical with the difference that the application head plays the role of the matrix. Advantageously, the flexibility of the application head makes it possible to shape the future restraining element as a function of the force exerted on the latter. The light source 124 (FIG. 13), for example a blue LED lamp, makes it possible to insolate, polymerize and therefore stick on the dental surfaces 2 the portion of the reinforcing preform 11 contained in the application head 117. transparent to light radiation, through the translucent and deformable material. Only the portion of the reinforcing preform 11 located at the application head 117 is exposed to the light radiation emitted by the LED lamp. The opaque tip 116 upstream of the orifice 115 preserves any insolation that can cause the polymerization of the remainder of the reinforcing preform 11. The reinforcing preform 11 is then tensioned by a lateral movement of the instrument while keeping a pressure on the dental surfaces 2 and the dihedral of the application head 117 is inserted into the next inter-dental space, and so on.

The entire dental compression element 1 is thus produced by application to the dental surfaces 2, transformation and polymerization, stepwise and tooth to tooth. According to a particular embodiment not shown, the handpiece comprises the light source 124 disposed on the gripping member 111 so as to insolate the application head 17. The light source 124 can be fixed on the gripping member 111 and oriented so as to insolate the application head 117 and polymerize the photopolymerizable resin 13.

The handpiece described above allows the dispensing and forming of a dental splinting element or splint as well as glue for bonding the splint to a tooth surface. The hand-held instrument allows the targeted polymerization of a portion of the reinforcement preform, transformed by the instrument in the second form, without polymerizing the remainder of the reinforcing preform. Similarly, the hand-held instrument according to the invention is shaped so as to conform to the complex surfaces, in particular thanks to its applicator head made of flexible and deformable material, in the form of a dihedron, capable of applying the preform in the inter-dental spaces.

The dental restraining element thus dispensed by the hand instrument according to the invention is in the form of an improved dental compression element which adheres intimately to the tooth surfaces. Thus, the use of the hand-held instrument described above with the preform makes it easier to break the band of contention.

In fact, it can be considered, according to a particular embodiment, that the head is configured to transform the preform 11 from the first tubular initial shape to the second form in the form of a strip or ribbon.

Claims

claims

1. Tubular dental reinforcing preform (11) formed by a tubular cord (12) made of braided fibers (8), characterized in that the cord (12) is impregnated and filled with a polymerizable resin (13) and is able to adopt , by isostatic crushing, a form of ribbon without rupture of the braided fibers (8) constituting the cord (12), the polymerizable resin (13) being able to flow through the cord (12) when the cord is subjected to the isostatic crushing.

2. Preform according to claim 1, characterized in that the cord (12) comprises a long fiber core (9) unidirectional.

3. Tubular reinforcement preform (11) according to any one of claims 1 to 2, characterized in that the cord (12) is selected from low-shape, woven or knitted cords.

Tubular reinforcement preform (11) according to any one of claims 1 to 3, characterized in that the tubular string (12) is filled with at least 38% by mass of polymerizable resin (13), said percentage being calculated relative to the total mass of the tubular reinforcing preform (11).

5. A method for producing a dental compression tape by means of the reinforcing preform (11) according to any one of claims 1 to 4, characterized in that it comprises the following successive steps:

- Shaping the initially tubular reinforcing preform (11) by exerting an isostatic pressure on said preform (11), the application of the pressure simultaneously making it possible to crush the initially tubular string (12) in the form of a ribbon and expelling the polymerizable resin (13) from the tubular cord (12) to form two side portions (7) on either side of the ribbon and polymerizing the polymerizable resin (13).

6. Method according to claim 5, characterized in that it comprises, before the shaping of the preform (11), the following successive steps: - achieve a negative impression (14) of the band of contention (1) dental by means of a matrix (15) from a reproduction (16) of said band (1), held in a specific position on a laboratory dental model (17) of an individual,

- housing the tubular reinforcement preform (11) in the negative impression (14) so that a portion of said preform (11) projects out of the cavity (14),

- Apply the matrix (15) provided with said preform (11) on the laboratory dental model (17) in the predetermined position.

7. Method according to claim 6, characterized in that the reproduction (16) is made from a wax analog.

8. Method according to one of claims 6 to 7, characterized in that the matrix (15) is applied and maintained in the predetermined position by means of a holder element (18).

9. Method according to any one of claims 6 to 8, characterized in that the matrix (15) is formed by a material selected from vinyl polysiloxanes.

10. Process according to any one of claims 5 to 9, characterized in that the polymerizable resin (13) is photopolymerizable.

11. The method according to claims 6 and 10, characterized in that the matrix (15) is transparent to light, and in that the step of polymerization of the photopolymerizable resin (13) is carried out by insolation of the matrix (15). ).

12. Method according to any one of claims 5 to 11, characterized in that, after the polymerization step, there is obtained a compression band of composite material based on a polymer material (4) and reinforcing means (5) formed by a braided fiber rope (8), said compression band (1) being formed by a central portion (6), comprising the reinforcing means (5), located between two lateral portions (7) constituted only polymeric material (4), said reinforcing means (5) being embedded in the polymeric material (4).

13. Dental compression band made of a composite material based on a polymeric material (4) and reinforcing means (5) formed by a braided fiber rope (8), said compression band (1) being formed by a part central unit (6), comprising the reinforcing means (5), located between two lateral parts (7) consisting solely of the polymeric material (4), said reinforcing means (5) being embedded in the polymeric material (4), characterized in what:

the compression band (1) has a thickness less than or equal to 0.7 mm,

said lateral portions (7) represent at least 8% of the total mass of said compression band (1), and

- said fiber rope (8) is flattened in the form of a ribbon.

14. Use of a hand-held instrument with a preform according to claim 1 for the application of a dental compression element (1), said instrument comprising:

- a gripping member (111) provided with a reservoir (112) receiving the dental reinforcing preform (11) in the pre-impregnated state before polymerization,

- application and forming means (114) of said preform (11), said preform (11) having a first initial shape and being adapted to adopt, by crushing, a second form, in the form of a strip or ribbon, distinct from the first form, the reservoir (112) communicating with the application and forming means (114) so as to dispense said preform (11) continuously, and the application and forming means (114) being shaped so as to apply said preform (11) while transforming it into its second form, and the application and forming means (114) having an opaque tip (116) to light radiation, terminated by an application head (117) transparent to light radiation .