DENTAL VENEERS AND METHODS OF MANUFACTURE
A dental veneer made from a composite comprising at least one organic binder, preferably with methacrylate, and inorganic solid particles as fillers.
This application is a divisional of U.S. patent application Ser. No. 13/730,946, filed Dec. 29, 2012, which is a continuation-in-part of International Patent Application No. PCT/AT2011/000285, filed Jun. 29, 2011, which claims the benefit of Austria Patent Application No. A 1124/2010, filed Jul. 2, 2010.
BACKGROUND1. Field of Invention
The present invention relates to dental veneers and methods of manufacturing dental veneers.
2. Technology Review
Dental veneers are known in the art and are frequently simply called “veneers”. They usually represent cup-shaped solid bodies, which are placed as faces upon perhaps previously ground teeth and/or tooth stumps, in order to provide a discolored tooth with the desired look. Here, they generally replace the natural front of the respective tooth.
Dental veneers are typically custom-made for a particle from a ceramic. First the required geometry of the dental veneer is determined via an impression of the ground tooth and/or tooth stump. Second, based on this information, the customized ceramic dental veneer is produced in the lab. Third, the dentist must then mount this dental veneer onto the tooth and/or tooth stump. In the event the dental veneer was not produced with sufficient diligence, a new dental veneer must be produced, because an adjustment to the conditions in the mouth of the patient by the dentist is not possible on site. This ultimately means that the patient must go to the dentist at least twice, until the fitting dental veneer is produced and mounted to the tooth. Additionally, this leads to the need of lab work with a considerable expense of time and money.
BRIEF SUMMARYDisclosed herein are dental veneers and methods of making and using such dental veneers. The dental veneers according to the invention relate to solid bodies, which can be placed upon a tooth stump and/or tooth prepared in the manner known from prior art, in order to appropriately cover the front of a discolored tooth and optically improve it. They can be adjusted in size during a single visit to the dentist, can have an appearance that matches the natural look of human teeth, can minimize the amount of natural dental tissue that is removed preparatory to attaching the dental veneer to a person's tooth, and can have a hardness that is similar to the hardness of natural teeth.
The disclosed dental veneers are generally made from composite materials comprising one or more types of binder and one or more types of solid particulate filler. According to one embodiment, the one or more types of binder comprise at least one methacrylate and the one or more types of solid particulate filler comprise solid inorganic particles. Fibers can also be added to the composites to add additional toughness, flexibility and durability. Because the dental veneers are made of composite, they do not have the extreme hardness of ceramic veneers (i.e., about 250 GPa) and are therefore adjustable in size. The hardness of the dental veneers can be similar to that of real teeth (e.g., about 17-20 GPa, preferably about 19 GPa) and be more flexible, less brittle, and more durable and tough than ceramic. This permits the disclosed veneers to be significantly thinner in cross section compared to ceramic veneers. This, in turn, permits less tooth material to be removed during preparation for receiving the veneer.
With regards to their exact size and/or shape, dental veneers as disclosed herein can be adjusted in size and/or shape on site by a dentist using common dental tool and thus be adjusted to the specific tooth conditions of the patient at the time the dental veneer is applied to the tooth surface. This permits production of non-customized dental veneers that can essentially be customized to a patient while at the dental office. This eliminates the need to have customized dental veneers produced in a lab.
In addition, and primarily due to the solid particles used as fillers, the disclosed dental veneers can have the required strength and hardness so that said tooth provided with the dental veneer can permanently perform its actual objective as a chewing tool.
The composite veneers can also be made according to a novel molding process, described in more detail below. According to one embodiment, the mold used to make the composite veneers can have both transparent (e.g., glass) and non-transparent (e.g., metal) surfaces. The mold can be heated to promote heat curing of the composite resin within the mold. In addition, the transparent surface permits light curing of the composite adjacent to the transparent surface. Such light curing can more quickly cure the composite adjacent to the transparent surface, which advantageously causes more polymerization shrinkage of the composite adjacent to the transparent surface adjacent to the transparent surface. This, in turn, draws the solid filler particles closer together and increases their density. The high pressure within the molds can further condense and consolidate the composite material together to increase composite density, strength, durability, glossiness, and other desired properties.
The disclosed dental veneers can be less hard and brittle and have increased toughness compared to conventional ceramic veneers. This permits the dental veneers to advantageously have a thinner profile so that less of the patient's natural tooth tissue needs to be removed preparatory to attaching the veneer. In addition, because they are not as hard as ceramic veneers, the disclosed dental veneers can be more easily adjusted to fit a patient's tooth or teeth, such as by means of a cutting or grinding tool. In addition, because natural tooth surfaces are not always perfectly dimensioned, the disclosed dental veneers can be altered, either before or after placement over a patient's teeth, to have a slightly irregular surface, such as by means of a grinding tool. In this way, they can have a more natural appearance compared to ceramic veneers, which can have an artificial appearance as a result of having a perfectly regular surface.
These and other advantages and features of the invention will become more fully apparent from the following description and appended claims, or may be learned by the practice of the invention as set forth hereinafter.
In order that the manner in which the above recited and other benefits, advantages and features of the invention are obtained, a more particular description of the invention briefly described above will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings. The following drawings depict only typical embodiments of the invention and are not therefore to be considered limiting of its scope:
Disclosed herein are dental veneers made from composite materials comprising one or more types of organic binder and one or more types of solid particulate filler.
With regards to their shape, dental veneers of this type can be processed on site by the dentist using the common tools of his/her practice and thus be adjusted to the conditions given in the patient. This eliminates the necessity of producing the dental veneers in a lab.
Similar to prior veneers, the dental veneers according to the invention have solid bodies, which may be placed upon a tooth stump and/or tooth prepared in manners known in the prior art, in order to appropriately cover the front of a discolored and/or damaged tooth and optically improve it. In one or more embodiments of the invention, dental veneers have solid bodies which are at least partially shaped in a curved cup-like fashion. Primarily due to the solid particles used as fillers, the dental veneers according to the invention also have a required solidity and/or hardness so that said tooth provided with the dental veneer can permanently perform its actual objective as a chewing tool.
In order to achieve high solidity of the dental veneer it is beneficial to arrange the solid particles of the filler packed as densely as possible in the dental veneer. For this purpose it is beneficial for the filler to comprise solid particles with grain sizes different from each other. In one or more embodiments of the invention, the dental veneers comprise macro particles in a range of 50 μm to 1 mm (e.g., about 500 μm), micro particles in a range of 1 μm to 50 μm (e.g., 5 μm), and nano particles in a range of 100 nm to 1 μm (e.g., 500 nm).
In order to achieve a high packing density, particularly small grain sizes are important here, because they fill the spaces between the larger grains. In this sense it is beneficial for the filler to comprise solid particles with grain sizes ranging from about 0.01 μm to about 3 μm. Additionally, in order to achieve higher solidity, the fill level of the composite must be as high as possible, which means the proportion of filler solid particles should be as high as possible (i.e., have high particle packing density). Beneficial variants of the invention provide that the filler solid particles be at least 75% by volume, preferably at least 82% by volume, in the composite of the dental veneer.
In one or more embodiments of the invention, the filler solid particles include glass, a mixture of several types of glass, or materials made therefrom. The types of glass may be different in color and composition. In one or more embodiments, the solid particles may comprise barium glass or strontium glass or mixtures thereof. In other embodiments, the solid particles may comprise aluminium-fluorosilicate glass, strontium-aluminium-silicate glass, barium-aluminium-silicate glass. In general, it may relate to a surface-treated SiO2. In alternative embodiments of the current invention, the solid particles comprise quartz, ceramic, pyrogenic silica, precipitated silica, x-ray opaque dental glasses, ytterbium trifluoride, highly dispersed silica such as ZrO2, Ta2O3 and TiO2 or mixed oxides of SiO2, ZrO2 and/or TiO2.
The veneers according to the current invention comprise an organic binder. One or more embodiments of the invention use a binder comprising mono-, di- or poly-acrylates and methacrylates. For instance, the organic binder in the composite may be made from one or more of the following: methyl acrylate, methyl methacrylate, ethyl acrylate, isopropyl methacrylate, n-hexyl acrylate, stearyl acrylate, allyl acrylate, glycerol diacrylate, glycerol triacrylate, ethyleneglycol diacrylate, diethyleneglycol diacrylate, triethyleneglycol dimethacrylate, 1,3-propanediol diacrylate, 1,3-propanediol dimethacrylate, trimethylolpropane triacrylate, 1,2,4-butanetriol trimethacrylate, 1,4-cyclohexanediol diacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, pentaerythritol tetramethacrylate, sorbitol hexacrylate, trishydroxyethyl-isocyanurate trimethacrylate, 4,4′-(4,4′-isopropylidene diphenoxy)-bis(hydroxyethyl methacrylate phthalate) (BPDP), bis glycerol dimethacrylate phosphate, bis 2-hydroxy ethyl methacrylate phosphate, p-hydroxyphenyl methacrylamide, 3-hydroxy propyl methacrylate, 4-hydroxy butyl methacrylate, triethylene glycol dimethacrylate (TEG-DMA), alkylhydroxy methacrylates, alkylamino methacrylates, urethane dimethacrylate (UDMA), butane diol dimethacrylate, and bisphenol-A-diglycidyl dimethacrylate (Bis-GMA), diurethane dimethacrylate (DUDMA), hydroxyethyl methacrylate (HEMA), methacrylic acid, and/or glycerol di-methacrylate (GDMA), mono-2-(methacryloyloxy)ethyl succinate (HEMA Succinate), hydroxypropylmethacrylate (HPMA), the bis-acrylates and bis-methacrylates of polyethylene glycols of molecular weight 200-500, copolymerizable mixtures of acrylated monomers, and copolymerizable acrylated oligomers, and the like.
In one or more embodiments of the invention, the organic binder may contain phosphoric acid derivatives and carboxylic acid derivatives of ethylenically unsaturated monomers. In alternative embodiments, the organic binder may comprise vinyl compounds such as styrene, diallyl phthalate, divinyl succinate, divinyl adipate and divinylphthalate.
The disclosed dental veneers are generally made from composite materials comprising one or more types of binder and one or more types of solid particulate filler. According to one embodiment, the one or more types of binder comprise at least one methacrylate and the one or more types of solid particulate filler comprise solid inorganic particles. Fibers can also be added to the composites to add additional toughness, flexibility and durability. Because the dental veneers are made of composite, they do not have the extreme hardness of ceramic veneers (i.e., about 250 GPa) and are therefore adjustable in size. The hardness of the dental veneers can be similar to that of real teeth (e.g., about 17-20 GPa, preferably about 19 GPa) and be more flexible, less brittle, and more durable and tough than ceramic. This permits the disclosed veneers to be significantly thinner in cross section compared to ceramic veneers. This, in turn, permits less tooth material to be removed during preparation for receiving the veneer.
An important objective when mounting dental veneers to teeth and/or tooth stumps is to control the coloring of the veneered tooth such that the conditions in the mouth of the patient are matched, i.e. the color of the veneered tooth is adjusted to the same color as adjacent teeth. In one or more embodiments of the invention, the dental veneer comprises a standard color, which resembles the color of natural tooth enamel. In other embodiments of the invention, the dental veneer is translucent and/or transparent, instead of opaque. In these embodiments, color can be adjusted by using an appropriately colorized bonding material (or bonding material), which is arranged between the dental veneer and the tooth and/or tooth stump when the dental veneer is mounted and shines through the translucent dental veneer. This way the color of the veneer can be adjusted to match the color of the overall environment. Examinations have shown that dental veneer with the following quality are preferable: translucency from about 28% to about 39% and/or a L-value of about 59 to about 69 and/or an a-value from about −0.35 to about −3.2 and/or a b-value from about −0.4 to about −6.95. Translucency relates to the light permeability, i.e. the reciprocal features of opacity. The values mentioned above relate to a measurement according to DIN 6174. The lab-color spectrum is known in prior art. It is designed based on the complementary color theory and allows one to determine a color value using color parameters and color intervals in an approximated uniform CIELAB-color range. The L-value, the a-value, and the b-value are also determined according to DIN 6174. When applying the complementary color theory, a-axis relates to the complementary colors green and red. The b-axis relates to the complementary colors blue and yellow. The L-axis is positioned perpendicularly in reference to this level and reflects brightness.
Based on its high solidity, the dental veneers implemented according to the invention may be made relatively thin. In one or more preferred embodiments of the invention, a dental veneer comprises a cutting edge at one of its end sections, preferably showing a thickness ranging from about 1.0 mm to about 1.3 mm. At regions outside of the cutting edge section, the dental veneer preferably has a thickness of about 0.6 mm, and/or tapers flat at its end opposite the cutting edge. Here, thickness is to be understood as the wall thickness in the respective area of the dental veneer.
One or more embodiments of the invention allow a dentist to adjust a dental veneer and/or a blank of dental veneer on site to match the geometric requirements of the tooth and/or the tooth stump of the patient. In one or more embodiments of the invention, the dentist has the chance to select a bonding material according to its color, thereby he/she can perform the desired color matching on site. A particular embodiment of the invention provides a set (or kit) of several dental veneers with various sizes and/or differently shapes. The set (or kit) additionally comprises at least one liquid or pasty bonding material and several different dyes for coloring the bonding material. In an alternative embodiment, the set (or kit) includes several differently colored, liquid or pasty bonding materials. The provided bonding materials are suitable to fasten or adhere the dental veneer to a tooth and/or a tooth stump.
Having a set of dental veneers as noted above allows the dentist to select a blank of dental veneer that most closely resembles the natural situation of the tooth or tooth stump to be treated. The remaining adjustment can then be performed by processing and/or cutting this blank on site. For this purpose, the dentist can use the cutting tools usually available. Further, the dentist can select the suitable dye and/or the appropriately colored fastening (or bonding) material, by which the dental veneer is fastened or adhered to the tooth stump and/or tooth, so that the desired coloring is achieved in the dental veneer fastened to the tooth and/or tooth stump. In one or more embodiments, the set (or kit) may comprise at least one bonding material and several different dyes by which the bonding material is colored by the dentist. In other embodiments, the set already comprises several differently colored bonding materials, in which the dye no longer needs to be mixed into the bonding material by the dentist. The bonding material may be pasty, i.e. mushy and/or thickly viscous. Organic pigments and/or the inorganic whitener TiO2 may be used as colorants to dye the bonding material.
In order to allow processing smaller fissures it is also possible to provide a liquid bonding material in the set. Particularly preferred embodiments of the set according to the invention provide that the bonding material, preferably provided in a pasty form, comprises the same or similar composite as the dental veneer of the set, however still in the pasty consistency. Further, it is beneficial when the bonding means, particularly provided in a liquid form, comprises the same organic binder as the dental veneer of the set, however still in a liquid form.
Advantageous embodiments of the set according to the invention additionally provide that the set comprises at least one adhesive agent, preferably at least two different adhesive agents, and/or at least one etchant. An adhesive agent serves to create a bond between the hydrophilic tooth and the hydrophobic composite of the dental veneer and/or the bonding means. In a prefer embodiment, the adhesive agent may also compensate shrinking forces of the bonding material. When at least two different adhesive agents are provided, one of them may be used as an adhesive agent between the tooth and the bonding means, and the other adhesive agent may be used between the bonding means and the dental veneer. Non-limiting examples of suitable adhesive agents include the products of the company Indigodental GmbH & Co. KG in Pinneberg, Germany, marked REF 2050 and REF 2051. The product REF 2050 may be used as an adhesive agent between the tooth stump and the bonding material. It includes methacrylated polyacrylic acid in a Bis-GMA based matrix. The product REF 2051 may be used as an adhesive agent between the bonding material and the dental veneer. This also relates to a Bis-GMA based methacrylate.
In one or more embodiments, the etchant is in the form of a corrosive gel, which serves to etch away the residual lubricants caused by the drill of the dentist and to expose the tubuli. Examples of suitable etchants include, but are not limited to, 15-37% concentrated phosphoric acid or the product REF 2052 of the above-mentioned company. It is also possible to use prepared mixtures of etchants and adhesive agents. Generally, the adhesive agents may include low-molecular methacrylates. Additionally, polymers showing a hydrophilic and a hydrophobic end may be used, such as methacrylated polyacrylic acid.
For example, the product of the company Indigodental GmbH & Co. KG in Pinneberg, Germany, available under the name REF 2061, may be used as the composite for the production of dental veneers as well as the bonding means. This product includes tri-ethylene glycol-dimethacrylate, urethane dimethacrylate, Bis-GMA, and ethoxylated biphenol A dimethacrylate. The product REF 2050 of said company, already mentioned with regards to adhesive agents, may be used as the organic binder.
Reference is now made to the drawings.
Accordingly, a relatively small number of sets of blanks is sufficient in practice. In one embodiment, they may be offered in three different size levels for the upper jaw and two different size levels for the lower jaw.
In the end section 4, the dental veneers 1 shown in a longitudinal cross-section are embodied as hook-shaped or graduated, at least at the back. In this configuration, the cutting edge 5, when the dental veneer 1 is applied to the tooth stump 10, forms the entire cutting edge of the tooth reconstructed in this manner. As is discernible in
For a large-area bonding, the bonding material 9b and 9c preferably comprise both the organic binder 2 as well as the solid particles 3. However, this material is relatively mushy and/or pasty as compared to more highly filled composites used to make the veneers. In order to allow the processing of very delicate surface structures, instead of this bonding material 9b and 9c, another bonding material 9a may also be used, which comprises, in addition to the dye, exclusively the organic binder 2 or at least a lower portion of solid particles 3. For instance, the bonding material 9a in one embodiment has 60 to 70% binder by volume. This bonding material 9a may comprise the same organic binder, preferably on a methacrylate basis. The bonding material 9a also has the same type and mixture of solid particles but at a lower concentration than the composite of the finished dental veneer 1.
In one or more preferred embodiment, an adhesive agent 11 is applied between the bonding material 9a, b, or c and the dental veneer 1. It is particularly preferred when this represents an adhesive agent 11 different from the adhesive agent 12. Suitable examples for adhesive agents have been described above.
One aspect of the invention relates to a dental set that allow a dentist to adjust and mount the dental veneer 1 to the tooth stump 10 during a single treatment session.
In addition to the dental veneers 1, the dental set according to
The bonding materials 9b and 9c represent differently dyed pasty bonding materials. Preferably, they comprise the composite of the dental veneer 1 in a not yet cured consistency. The bonding materials 9b and 9c therefore comprise both the organic binder 2 as well as the solid particles 3.
With the help of a color key 14 the dentist can select the appropriately dyed bonding material 9a, b, or c and use it in the manner indicated in
In the exemplary embodiment shown, the dental set (or kit) according to
Additionally, the set according to
Another aspect of the invention relates to methods for manufacturing the dental veneers 1 from the composite material mentioned above.
Specifically, in one or more embodiments of the invention, the composite comprising the organic binder 2 and the solid particles 3 is first injected into a cartridge. The composite is heated to an appropriate temperature, which softens the composite for processing and molding. The composite may also be pressurized to a pressure between about 80-100 bars. Light curing of the composite is performed by shining light through a transparent side of the mold with a suitable LED light.
In one or more embodiments of the invention, the suitable LED light is characterized, for example, by a wavelength from about 450 nanometers (nm) to about 480 nm. In one or more embodiments of the invention, the composite may comprise one or more photo initiators to facilitate the light curing process. Examples of suitable photo initiators include benzophenone, benzoin and derivatives thereof and a-diketones and derivatives thereof, such as 9,10-phenanthrenequinone, 1-phenyl-propan-1,2-dione, diacetyl and 4,4-dichlorobenzil. Camphorquinone, 2,2-methoxy-2-phenyl-acetophenone or a-diketones, each in combination with amines as reduction agents, such as e.g. 4-(dimethylamino)-benzoic acid esters, N,N-dimethylaminoethyl-methacrylate, N,N-dimethyl-sym.-xylidine or triethanolamine, as well as monobenzoyl- or dibenzoyl germanium derivatives, are preferably used.
The blank of the dental veneer 1 is removed from the tooth mold. In one or more preferred embodiments of the invention, a continuously cured layer as the surface of the dental veneer 1 is formed. Care is taken in the process to prevent this cured layer from delaminating from underlying composite. In one or more embodiments of the invention, this layer is provable by a cross-section through the dental veneer 1 and preferably has a thickness ranging from about 10 to about 20 μm.
In one or more embodiments of the invention, the mold for shaping the veneer is at least partially cup shaped.
In a preferred embodiment of the invention, the mold is transparent on the side shaping the facial surface of the dental veneer 1. The transparent side of the mold allows for light curing of the composite at the facial surface, and can be made of transparent materials such as inorganic or organic glasses.
In one or more embodiments of the invention, it is advantageous to use a filler according to the invention based on a silanized glass in order to improve the mechanical properties of the cured dental material. The term “silanization” used herein means the functionalization of the glass surface with polymerizable silanes, such as by reaction with (meth)acrylate-functionalized silanes, e.g. (meth)acryloyloxyalkyl-trialkoxysilanes, usually 3-(methacryloyloxy)propyl-trimethoxy-silane, 3-(methacryloyloxy)-propyltriethoxysilane, 3-(methacryloyloxy)-propyltrichlorosilane, methacryloyloxymethyltrimethoxysilane, methacryloyloxymethyltriethoxysilane, 3-(methacryloyloxy)-propylmethyldichlorosilane or 3-(methacryloyloxy)-propylmethyl-dimethoxy silane. Among the examples of silanes above, 3-(methacryloyloxy)-propyltrimethoxysilane is preferred. The silanization of the glasses takes place in conventional manner and is known to a person skilled in the art. Although it may be preferably to silanize all the filler particles, it may be desirable to not silanize nano-sized particles to prevent or minimize agglomeration.
Finally, cutting or post-processing of the cured composite may occur to yield the final product. The final processing may include, but are not limited to, cutting the veneer to achieve correct size and shape, grinding and/or smoothing edges and surface, and creating minute surface texture to achieve a realistic look instead of a perfectly uniform but fake look.
The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.
Claims
1. A tooth front veneer, wherein the veneer consists of a composite material, the composite material containing at least one organic binder, preferably with methacrylate, and filler particles, preferably inorganic filler particles, as solid.
2. A tooth front veneer according to claim 1, wherein the veneer is curved in a shell-shaped configuration, at least regionally.
3. A tooth front veneer according to claim 1, wherein the solid particles of the filler comprise or consist of glass or a mixture of different types of glasses and/or that the filler contains solid particles of different grain sizes, preferably grain sizes of between 0.01 μm and 3 μm.
4. A tooth front veneer according to claim 1, wherein the solid particles of the filler constitute at least 75% by volume, preferably at least 82% by volume, of the composite material of the tooth front veneer.
5. A tooth front veneer according to claim 1, wherein the veneer is translucent, preferably exhibiting a translucency between 28% and 39%, and/or has an L value of 59 to 69 and/or has an “a” value of −0.35 to −3.2 and/or has a “b” value of −0.4 to −6.95.
6. A tooth front veneer according to claim 1, wherein at one of an end region, the veneer having a cutting edge, preferably with a thickness between 1 mm and 1.3 mm, and/or the tooth front veneer having a maximum thickness of 0.6 mm outside of the end region with the cutting edge and/or the tooth veneer running out flat at an end opposite to the cutting edge.
7. A kit comprising several tooth front veneers of claim 1, the kit additionally comprising at least one, preferably liquid or pasty, fastening material and several different colors for coloring the fastening material and/or several differently colored, preferably liquid or pasty, fastening materials, the at least one fastening material or the several differently colored fastening materials being suitable for fastening, preferably adhering, the tooth front veneer to a tooth stump.
8. A kit according to claim 7, wherein the fastening material contains the same composite material or the same organic binder as the tooth front veneer.
9. A kit according to claim 7, wherein the kit comprises at least one adhesion promoter, preferably at least two different adhesion promoters, and/or at least one etching material.
Type: Application
Filed: Sep 13, 2016
Publication Date: Jan 19, 2017
Inventor: Stephan Lampl (Kriessern)
Application Number: 15/264,217