This patent document refers to configurations applied in copings and fiber bars, for manufacturing fixed dental prosthesis frameworks. Is also matter of this patent document the method of obtaining the referred frameworks for fixing dental prostheses, using one of these copings here presented and the fiber bars.
Partial or total dental prostheses represent a significant volume in the dental market and are the most practical solution for returning masticatory and aesthetic functions to toothless people and, in addition, to giving back their self-esteem. The most common types are “mucosal supported dental prostheses” (they are loose and rest on the oral tissue gums and palate), “prostheses attached to implants”, with attachment type devices (they are fixed and retained by means of pressure), and “prostheses attached to implants by means of screws” (protocol-type prostheses). In relation to the comfort, fixed prostheses have gained preference, as they represent much more security for the user that they will not move unintentionally.
Modern dentistry has presented several options for obtaining these fixed prostheses, the most common and least expensive is the prosthesis obtained from artificial teeth, made of acrylic resin, cast metallic infrastructure and aesthetic coverage also of acrylic resin. The masticatory force in fixed prostheses on implants is exerted on the entire surface of the prosthesis, but discharged only on the implants, since the spaces between implants (or in addition to these in the distal ones) are not mucosupported spaces. Failures are more frequent due to the presence of discontinuities in the molten metal bar (bubbles, for example), poorly made seams, etc., and failures can also occur due to poor connections between the bar and the coping (element known in the segment), resulting in poor adhesion of these during the fusion process, which ends up generating small thicknesses around the coping and consequently a certain “fragility” and possibility of fracture at this point on the coping, a term known as “cantilever”. Another inconvenient point is the fact that the spaces between implants are flexed and therefore can result in failure due to material fatigue.
Currently, different types of obtaining dental prosthesis frameworks are known, among them, can be cited: a) “molten metals” obtained by melting metals developed for this function. They are quite resistant, but they are also quite difficult to obtain, as it requires several steps, such as molding the patient, obtaining the mold for the arch and then subsequently manufacturing the prosthesis; b) the “prefabricated metallic structures” that aim to make the process of obtaining metallic infrastructures more agile, they are metallic components that fit together and allow to form the metallic bridges between support points in the implants, simulating the molten metallic infrastructure; c) those of “intraoral soldering with titanium wires” that use spot welding devices that allow fixing titanium wires to the components that fit over the implants, however this method is not the most effective; d) “infrastructures machined from ceramic materials” which are infrastructures machined from materials and equipment using the CAD/CAM technique; these materials, as a rule, require melting or sintering at high temperatures and are used for techniques that use ceramics to obtain 100% of the prosthesis; however, the manufacturing costs are quite high; and e) “structures machined in fiberglass and resin composites” that use pressed and prepolymerized fiberglass and epoxy resin (or polyester) composites, cut into a horseshoe shape, where they are milled and adapted for the most suitable shape of the prosthesis and then joined by gluing to the fixation tubes on the implants; this has some advantages such as the speed with which it is possible to obtain the infrastructure, it has greater lightness compared to metal and even ceramics; however, as disadvantages we have the need for machining to shape the final prosthesis (tool consumption, generation of fiberglass dust, etc.) and, sometimes, the error of not keeping enough structure for resistance beyond the last implant (term known as “cantilever”).
In this technical field, more specifically about the method of obtaining from fiberglass and resin composites (item “e” of the previous paragraph), there are already several procedures and techniques known for this purpose. Among these, the most noteworthy are those that use elements known technically as copings, where basically the bars composed of bundles of fiberglass, impregnated with photopolymerizable resins are positioned by the professional, in these elements (the copings), and then later photopolymerized thus forming the infrastructure; the closest technique publicly known on this occasion, which can be cited is the one known commercially as CST (Cable Stayed Framework), where exactly the described technique is applied: fiber bars with resin, distributed by the support elements (copings) and later photopolymerized.
A first problem associated with this technique is the difficulty in orienting and positioning the fiber bar. Technically, in this type of obtaining the framework, the bar made up of bundles of resinous fiber must pass at a certain height from the alveolar ridge, and to facilitate the folds that will be made in the bundle, as well as positioning them properly at this certain height makes it ideal it is a very complicated task for the professional, as it is very difficult to maintain a reference that guarantees a standardization in the distribution and positioning of the bar during the manufacturing process of the framework. It is a laborious technique and should be done extra-orally.
This first problem also brings with it another problem, which is the difficulty of handling the professional who will manufacture the framework, since such guidance will depend, to a great extent, on his manipulation skills, as he currently does not have a significant standardized reference to assist him. In addition, as the fiber bar is malleable, it becomes more difficult to maintain the arc shape shaped by the professional.
This first problem presented can also results in other problems, such as, for example, a poor mechanical distribution of loads in the masticatory function; because, from the mechanical point of view, if the fiber bar is poorly distributed, there will not be a balance throughout the entire infrastructure.
Another problem that can be raised in this type of technique for obtaining this framework from resin fibers is the fact that the adhesion between the resin fiber and the metallic element (coping) would be more effective if there is a mechanical support as an aid element, as well as the bar itself had a more suitable shape, with its flattening, for example, to facilitate its insertion.
Besides, the flattening of the fiberglass bar, this being done at the time of use, by the professional himself, using a suitable instrument, such as pliers or tweezers, results in an effect with temporary duration, since the bundle of fibers that form the bar tends to return its initial shape, with cylindrical cross section, when the pressure stops. Therefore, the deformation made, by a forced way, by the professional, will represent a very superficial and even temporary beneficial technical effect, besides resulting in losses of time and efforts that could be avoided.
The object proposed in this document, is in the technical field of dental frameworks obtained through composite material (fiberglass) and light-cured resin; it presents configurations applied in coping, and in the fiber bar that result in a solution to all the problems previously presented, besides allowing a totally innovative method of obtaining the referred prosthesis frameworks.
In relation to coping, the applied configurations is more specifically to provide at least a “hook” element incorporated to said coping, which solves the problem in a unique way, of the difficulty of orientation and positioning of the bar composed by the bundle of resin fibers; this configuration applied to coping, (we will call it a coping with hook or hooks) facilitates its manipulation by the professional when building the framework, standardizing the positioning of the fiber bundle, helping to improve the mechanical distribution and helping with better adhesion (retention) from the resinous fiber to the metallic element, guaranteeing the maintenance of the shape given to the resin before light curing, among many other advantages associated with this improvement.
Regarding the fiber bar, the applied configurations are due to the fact that it is obtained from a bundle of parallel fibers, not fragmented and aligned longitudinally and that it is covered by a braided layer of glass fibers; and said fiberglass bar is deformed, so that its cross section has an oblong or flat shape, by a longitudinal seam or another longitudinal fixation, along the central region of said fiber bar; this longitudinal seam will result in permanent deformation, making the fiber bar with oblong (or flat) cross section in its natural condition. The beam bar with oblong (or flat) cross-section, in addition to eliminating the need to be forced by the professional and all the inconveniences associated with it, as mentioned above, also brings a series of more evident advantages, such as: facilitate the insertion of the bar in the coping hooks, increase the fracture resistance of the framework in the direction of chewing, decrease the volume of the bar in the lateral direction, gaining space for molding/assembling the structures that will represent the gum and teeth of the future prosthesis.
In addition to the proposed solution, to solve these mentioned problems, the method of obtaining fixed dental prosthesis frameworks is also the matter of the invention, using one of the copings configurations with the hook incorporated; This method allows adjustments directly in the patient's mouth and will be described in detail below.
Coping, as is already known in this technical field, is a cone-shaped, tubular element, based on a shape that fits over the head of the prosthetic component and allows its fixation on it by means of a screw or by pressure; this component, the coping, is already part of the current process of manufacturing protocol prostheses with metallic infrastructure. However, the object of this application is the applied configurations developed to make the proposed method feasible and are characterized by comprising at least one side hook, incorporated to said coping, preferably starting from its base and projecting up to little more than half height of the coping body. The hook incorporated represents innovation in coping, as it allows positioning and organizing the fiber bar in a position close to the coping and receives the bite pressure transmitted through the polymerized fiber bar and transfers the bite pressure to the prosthetic components/implants.
The object of this document is also the fiberglass bar, which is obtained from a bundle of parallel fibers, not fragmented and aligned longitudinally and this is covered by a braided layer of fiberglass. This arrangement of the bar and the constructive configuration of coping with the hook incorporated, enables the best obtaining of the prosthesis frameworks, also described in this document. Said fiberglass bar can be deformed, so that its cross section has an oblong shape, or flattened; for this, a longitudinal seam, or another longitudinal fixation is necessary, along the central region of the fiber bar.
The referred coping, in its broadest inventive idea, comprises a body in the shape of a cone-shaped trunk, hollow, and comprising at least one hook incorporated to said body. Said hook, it can be built in a single body with the cone trunk, or it can be a secondary, spare, assembled and properly fixed to the coping later. Said coping provides for at least one hook incorporated, however two hooks, or more, can be provided, aligned or misaligned in relation to each other.
There are other formats for fixing the prosthesis, in addition to screwing, which can be used within the context of this framework and coping with hook. Examples are cemented prostheses and prostheses with attachment. Thus, the object of invention “coping with hook” could have other formats to meet the type and fixation desired. In other words, the referred “coping with hook” can be of the screwed, cemented or attachment type. More broadly, the coping configuration, here claimed, comprising at least one hook, can be adjusted, in terms of its design, to suit all different types of implant systems (all different brands and models), without that the essence of the invention is lost.
This hook or hooks, incorporated to the coping, can have a varied constructive format, as long as it is compatible to receive the constituent element of the framework composed of the bundle of resin fibers and the photopolymerizable polymeric material.
It is characteristic of the configuration applied to coping to provide at least one hook to receive fiber bars, as well as to support the efforts of the framework and assist in the adhesion of the fiber bundle to the metallic element (the coping itself), helping still maintaining the molded shape of the beam while not polymerized.
It is characteristic of the configuration applied to the fiberglass bar, to be obtained from a bundle of parallel fibers, not fragmented and longitudinally aligned and this one to be covered by a braided layer of fiberglass. And said fiberglass bar can be deformed, so that its cross section has an oblong shape, or flattened; for which a longitudinal seam or another longitudinal fixation is necessary, along the central region of said fiber bar.
The characteristic of this configurations using these copings and the fiber bar, is the fact to bring significant improvements, in the positioning, orientation, standardization and mechanical distribution of the resin fiber bundle at the moment of the fabrication of the framework, resulting in the improvement of the function masticatory.
It is also characteristic of the invention that the hook incorporated to the coping allows the fiber bar to be juxtaposed to the coping and to remain organized, with all the fibers of the bundle intact and dense in the form of a rigid and resistant column, a necessary condition for the maximum mechanical strength is obtained solves the problem of split structure around the coping (one half of the bar on each side of the coping), which is often the cause of cantilever fracture.
In addition to these advantageous features, we can also mention the improvement in the surface visual aspect of the prothesis framework.
It is characteristic of the method of obtaining the dental prosthesis framework that it is easy and practical to obtain and allows adjustments directly in the patient's mouth.
It can also be mentioned that the fiberglass infrastructure is stiffened in the mouth by means of photopolymerization, a solution that allows to quickly obtain an infrastructure that captures and remains faithful to the position of the prosthetic components/implants, a fundamental characteristic for the good fitting of the future prosthesis. The polymerization of the fiber bar in the mouth also allows the professional to adjust the position of the bar in the ideal position for the strength of the prosthesis, at the time of polymerization. In this way, it is possible to move the beam position according to the best convenience or need and to polymerize the structure only when the appropriate position has been reached. This is particularly interesting when considering the position of the bar in the posterior region (cantilever), which has the most critical and important role in this prosthesis framework.
The fiber bar, which is part of the infrastructure, is preferably composed of a braided layer of glass fibers, and inside it runs a bundle of parallel fibers, not fragmented and aligned longitudinally. The intact bundle, with parallel and aligned configuration, brings a high flexural strength to the fiber bar to better adapt to the hooks. And the longitudinal seam along the central region of the fiber bar can be made by different means of fixation, such as resistant thread, or metal clamps, or rivets, or other compatible means.
It is also possible to mention some comparisons with the CST technique, mentioned above, the bar composed of fiber bundles proposed here is much more resistant than the bundles of the CST technique, besides being faster and easier to apply. Due to the characteristics of thickness and method of application, the fibers of the CST technique are not an adequate solution to form a cantilever of adequate strength. In addition, the fiber bundle bar proposed here is equipped with a braided cover that allows the organization of the bundle to be maintained and its easy handling while not polymerized. Also its longitudinal seam guarantees its natural flattened shape.
It is also characteristic of the method of obtaining the proposed prosthesis framework, the minimization of errors in its manufacture, as well as the optimization of its obtaining speed.
The figures follow presented, by way of example and illustration, will facilitate the understanding of the matter described and claimed in this document. The images presented are representative and serve to illustrate the different possibilities for configuring copings, and the configuration applied to the fiber bar and illustrations that facilitate the understanding of the method of obtaining, in order to allow a person skilled in the art understanding the inventive concept pleaded in this patent document, not excluding other constructive possibilities not illustrated, as well as combinations of these presented.
In reference to the figures presented, this patent document referring to the configurations applied in copings and fiber bars for the manufacture of fixed dental prosthesis framework. In relation to coping, in its broader inventive idea it comprises a body in the shape of a cone-shaped trunk, hollow, and comprising at least one hook incorporated to said body. Referred hook, it can be built in a single body with the cone trunk (figures from 01 to 10), or it can be a secondary, spare, assembled and properly fixed to the coping later (
Said coping provides for at least one hook incorporated, however two or more hooks may be provided, aligned or misaligned in relation to each other. And, in addition to the variation related to the number of hooks and their spare construction, coping with a hook incorporated, the object of this document, can provided for numerous other construction variations, such as recesses, chamfers, among other details. The absence to illustrate all the possible constructive variations does not detract from the inventive step of the matter of this patent document.
As already presented,
Already as shown in
Regarding the fiber bar (700), they are illustrated in
Remembering that these figures are illustrative to better understand the object proposed in this document, and to facilitate interpretation and understanding for a person skilled in the art; thus, some variations of these configurations, as well as the combination of constructive details of an illustration with details constructive elements of another illustration, or even combinations with constructive details not illustrated, should not mischaracterize the object here presented or to be understood like an improvement of these examples.
Thus, in a conceptual way, the object proposed in this document, is a coping with a hook incorporated, the fiber bar (700) with the light-curing resin in order to enable a totally innovative method of obtaining fixed prosthesis framework. It is important remembering that the hooks, incorporated to the coping, can have a different constructive format, (with recesses, spares, chamfers, with more than one hooks, as well as compatible for different types of seats, etc.), as long as it is compatible to receive the constituent element of the framework composed of bundles of resin fiber and the photopolymerizable polymeric material; preferably the hook part goes from the base region and protrudes up to half the height of the coping body approximately. This hook represents innovation in coping, as it allows positioning and organizing the fiber bar (700) close to the coping, receiving the bite pressure transmitted through the polymerized fiber bar (700) and transferring the bite pressure to prosthetic components/implants, it helps to guide the fiber bundle and all the other advantages already mentioned and explained in this document.
The method of obtaining the fixed dental prosthesis frameworks using one of the copings with configurations here presented, as well as one of the configurations of the fiber bar (700) presents, is also the matter of this patent document, since it was to enable the present method of obtaining framework that the configurations of copings and fiber bar, already described, were developed. The proposed method comprises the use of coping with specific configuration as already described and presented in this document, it also comprises the use of a fiberglass bar together with a fluid photopolymerizable resin.
One of the copings (100, 200, 300, 400, 500, or 600), as already presented, with its specific configuration and variations, already described above, consists of the element that will support the glass fiber bar (700).
The glass fiber bar (700), also object of this patent document, is comprised of a braided layer (701) of glass fibers and inside it runs a bundle (702) of parallel fibers, not fragmented and aligned longitudinally. The intact bundle (702), with parallel and aligned configuration, brings to the fiber bar (700) high flexural strength. Said fiber bar (700) can also provide seam (703), as already described.
The glass fiber bar (700) is impregnated with a photopolymerizable resin composition. While not polymerized, it is malleable and allows its shape adjustment to fit the coping hooks and acquire the shape of the prosthesis arch. This photopolymerizable resinous composition covers the entire class of Acrylic and Methacrylic monomers; preferably a composition based on urethane diacrylate (UDA), TEGDMA, and photoinitiator composition is being used; this monomer was selected because it allows rapid polymerization and provides high rigidity to the fiber bar after polymerization. Compositions containing the classic methacrylic monomers can also be used.
When irradiated with blue light from a dental curing light, the resin polymerizes and stiffens the glass fiber bar (700). When photopolymerized, the fiber bar adheres to copings, becomes highly rigid and defines the shape of the framework of the future prosthesis. By stiffening and adhering to the copings, the bar already captures the exact position of the prosthetic components/implants. To facilitate the handling of the bar while not polymerized, it can be covered with a plastic film, glass powder or other material that gives it a dry appearance.
In order to avoid disorganization of the bundles (702) inside the fiber bar (700) and also to facilitate their installation in the coping hooks, one end of the bar may have the bundles (702) and braided cover (701) attached by a ring, clamp or any device or simply have a small segment on the pre-polymerized end.
In order to increase the mechanical properties of the polymerized Fiber Bar, the braided cover (701) and bundle (702) of fibers can be treated with silanes or other coupling agents before being impregnated with the light-curing resin.
The composition of the glass fiber bundles (702) that are suitable for obtaining the bar covers the entire variety of glass fibers, such as type A, type C, type D, type E, type R, type S (S-1, S-2 and S-3) type ECR, type AR and others. Still, viable alternatives are Quartz, Carbon fibers, Aramid fibers (popularly known as Kevlar), Polypropylene fibers, polyester fibers and other examples that the high-performance mechanical fibers market can offer.
Alternatively to what is proposed for the current fiber bar (700), the fiber bundles (702) can still be braided in the form of ribbons or bars, elements already known in the technical field, however also compatible for the proposed method of obtaining. Furthermore, said fiber bar (700) can provide for other specific construction configurations, which may facilitate the proposed method of obtaining and manufacturing.
The fluid photopolymerizable resin, the third component for the method of obtaining the infrastructure described in this document, comprises a composition identical to that used to impregnate the fiber bar, plus loads to obtain greater mechanical resistance and eventually pigments. This resin assists in the process of fixing the bar on the copings and assists in camouflaging the hooks of the copings so that they do not harm the aesthetics of the prosthesis, if thinner walls in the prosthesis allow such part to appear.
Obtaining, or manufacturing, the fixed prosthesis frameworks comprise a procedure based on a standard prosthesis protocol, and
In this way, it is possible to accurately capture the position of the prosthetic components and production the rigid framework (an example in
Number | Date | Country | Kind |
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10 2019 007006 4 | Apr 2019 | BR | national |
13 2019 025338 9 | Nov 2019 | BR | national |
Filing Document | Filing Date | Country | Kind |
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PCT/BR2020/050105 | 3/30/2020 | WO | 00 |