Multi-component adhesive composition for use in the production of dental restorations

Abstract

The present invention describes a multi-component adhesive composition for use in the production of dental restorations, to the method for producing dental restorations in which the multi-component adhesive composition is used as an adhesive, and to the provision of a controlled dispensing device for applying the multi-component adhesive.

Description

[0001] Multi-component adhesive composition for use in the manufacture of dental restorations

[0002] The present invention relates to a multi-component adhesive composition for use in the manufacture of dental restorations, the method for producing dental restorations in which said multi-component adhesive composition is used as an adhesive.

[0003] DE102005039590B4 describes a polymerizable dental composition with a two-component initiator system. The dental composition exhibits significantly increased initiation activity and is used for the production of dental resins.

[0004] DE102005041115A1 describes a sealing and filling composition for filling and / or sealing a dental root canal.

[0005] EP3280348B1 describes a method for producing partial or complete dentures using rapid prototyping.

[0006] EP4039220A1 discloses a dental material based on polymerizable thioureas.

[0007] US 4,792,577 discloses an orthodontic adhesive consisting of two components that become reactive and cure without mixing when two layers of the different components come into contact. The first component has a relatively low viscosity and contains an acrylic or methacrylic diester of ethoxylated bisphenol A, an acrylic or methacrylic diester of an alkanediol, and benzyl acrylate or methacrylate. The second component contains a filler and an acrylic or methacrylic diester of ethoxylated bisphenol A, an acrylic or methacrylic diester of an alkanediol, and benzyl methacrylate or acrylate, the filler being present in amounts ranging from 50 to 80% by weight based on the second component. One of said components contains a peroxide-based catalyst, and the other component contains a tertiary amine as an activator for the peroxide catalyst.EP 3 944 837 describes a method for producing a plate prosthesis comprising the steps of: preparing a prosthesis plate having a concave socket formed thereon and a vertical groove formed on a bottom surface of the socket; applying an adhesive material to the socket and the vertical groove; embedding a reinforcing structure in the vertical groove to which the adhesive material is applied; and arranging an artificial tooth in the socket to which the adhesive material is applied.

[0008] Removable and partially removable dentures usually consist of various components from different material classes. Combining these materials in the final dental restoration still requires complex manual work. For example, the elements that replicate the tooth and gingival structures primarily serve to faithfully replicate the appearance of these structures. These structures are usually made of polymer-based materials, which can include unfilled plastics and polymer-based composites. The elements that serve to fix the restoration to implant or residual tooth structures and / or stabilize the tooth and gingival replicas are usually made of metal alloys or high-performance polymers.

[0009] The commonly used procedure is to combine the above-mentioned structures, which consist of different material classes, usually by modeling the gingival elements on a plaster model from wax that bonds the previously fabricated tooth elements to the previously fabricated fixation elements. This wax is then modeled by hand to replicate the gingival shape. Once the final shape of the dental restoration has been defined in this way, a silicone mold is used to create an impression of the modeled shape of the wax and the position of the tooth element. The wax is then removed from the plaster model, fixation elements, and teeth using hot water or steam, the plaster model is insulated, the fixation elements are opaqued to prevent the often metallic color from shining through the gingiva and tooth portions, and the teeth are fixed in the silicone mold.The areas that previously defined the gingiva with wax are then filled with gingiva-colored cold or hot-curing polymer, which also creates the bond between the fixation elements and the teeth during polymerization. The excess polymerized resin is then removed and polished with rotating instruments.

[0010] Thus, state-of-the-art dental restoration consists of the following points:

[0011] - Production of the scaffolding

[0012] - Adaptation of the prefabricated teeth to the framework structure

[0013] - Fixation of prefabricated teeth using wax

[0014] - Modelling of the gingival parts using wax

[0015] - Impression of this model including teeth using silicone matrix

[0016] - Removal of wax

[0017] - Preparation of the framework (conditioning of the framework using, for example, corundum blasting and / or primer)

[0018] - Opacification of the framework

[0019] - Preparation of the teeth

[0020] - Preparation of the plaster model

[0021] - Fixing the teeth in the silicone matrix and placing the framework and the silicone matrix with the teeth on the plaster model

[0022] - Mixing a pink cold or hot polymer

[0023] - Flow of the liquid pink plastic into the silicone matrix

[0024] - Curing in a pressure pot

[0025] - Lifting the composite part from the model

[0026] - Removal of excess material using manual milling and manual polishing.

[0027] As a result, the current state of technology means that final dental restorations still require laborious manual work. Furthermore, the different material classes cannot be processed automatically, as the shape and appearance of the dental restorations are individually tailored to each patient and vary greatly in shape and appearance from patient to patient. Even if the gingiva and tooth elements were fabricated in advance, the fixation element must always be opaqued first, and in a subsequent step, this opaque element must be bonded to the gingiva or tooth material.

[0028] Consequently, there is a need in the state of the art to significantly simplify or reduce the manual work involved in dental restorations. Furthermore, the current state of the art uses various adhesives or polymers to bond the various materials used in dental restorations.

[0029] Furthermore, there is also a need in the state of the art for a suitable adhesive that both creates the bond between the fixation elements or the restoration part and, in the best case, covers the color of the fixation element and adapts it to the restoration part.

[0030] With regard to color, it is important that the substructure is covered before further use, as otherwise it will show through the semi-translucent resin that replicates the gingiva. The challenge here is to adjust the pigmentation so that the material provides coverage even in thin layers. In the prior art, opaques are applied in multiple layers, each layer being light-cured until the desired degree of coverage is achieved. However, within the scope of the present invention, the first layer must be sufficient, as the components are bonded in the same step, and no further adjustments are possible afterward.

[0031] Surprisingly, it has been shown that by a suitable design of the fixation element as well as the tooth and gingival parts in combination with the multi-component adhesive composition mentioned here, which creates the bond between the construction elements and also covers the substructure, the work steps in dental restoration can be significantly reduced.

[0032] Preferred embodiments of the multi-component adhesive composition for use in dental restoration are further described below, wherein all features can be combined with one another in any desired manner and do not limit the multi-component adhesive composition in the present invention.

[0033] The present multi-component adhesive composition for use in dental restorations provides that the adhesive corresponding to the multi-component adhesive composition both creates the bond between the fixing element and the restoration part and also covers the color of the fixing element and matches it to the color of the restoration part. Furthermore, the multi-component adhesive composition can achieve opacity and bonding in a single step. Furthermore, according to the present invention, a dosing device is provided that can be used to apply the multi-component adhesive.

[0034] In a first embodiment, the object underlying the present invention is achieved by providing a multi-component adhesive composition for use in the production of dental restorations comprising at least a first component A and a second component B, component A comprising at least the following: i. at least 35% by weight of a crosslinker, preferably urethane dimethacrylate (UDMA), ii. at least 5% by weight of polymerizable components based on (meth)acrylate, iii. at least 15% by weight of fillers, preferably organic fillers and / or inorganic fillers, which are optionally surface-functionalized, iv. optionally at least 0.5% by weight, preferably 5 to 20% by weight, particularly preferably 8 to 18% by weight, in particular 10 to 16% by weight of color pigments, v. optionally at least 1% by weight of a polymerizable component having at least one OH group and / or an -NR / R 2 Group, where R 1 and R 2, are each independently selected from the group consisting of H, C 1 -C 8 alkyl and C 5 -C 8 cycloalkyl, vi. at least 0.5 wt.% of a thiourea derivative vii. less than 1 wt.% of a transition metal-based catalyst viii. optionally one or more photoinitiator(s), preferably in an amount of at least 0.5 wt.%, more preferably from 2 to 14 wt.%, in particular 4 to 12 wt.% or 6 to 12 wt.%, where the weight data are in each case based on the total weight of component A and where component B comprises at least the following: i. optionally methyl methacrylate, ii. at least 30 wt.% of one or more mono- or multifunctional (meth)acrylate monomers, iii. at least 15 wt.% (in)organic fillers, iv. one or more hydroperoxide initiators, in particular cumene hydroperoxide, the weights being based on the total weight of component B.

[0035] The multi-component adhesive composition provided for use in the fabrication of dental restorations combines opaque bonding and bonding in a single process, eliminating several steps and resulting in significant cost savings. Furthermore, the use of only one material to fill the predefined bonding gap enables a significantly better fit. The definition of a bonding gap can be achieved by constructing spacers on the gingival portion or the fixation element.

[0036] According to the invention, component A in the present multi-component adhesive composition comprises at least 35% by weight of a crosslinker (hereinafter also: Ai).

[0037] The crosslinker may comprise one or more compounds.

[0038] The crosslinker is preferably present in an amount of 20 to 80 wt.% or 35 to 80 wt.%, more preferably 35 to 70 wt.%, particularly preferably 40 to 55 wt.%, in each case based on the total weight of component A.

[0039] Typically, crosslinkers are compounds that carry two or more radically polymerizable groups, in particular acrylate and / or methacrylate groups.

[0040] The crosslinkers preferably have one or two or more isocyanate groups (-NHCO-) ​​(urethane groups).

[0041] A particularly preferred class of crosslinkers, with which particularly good results in terms of biocompatibility and opacity have been achieved, are urethane dimethacrylates (UDMA). UDMA has proven to be a particularly suitable crosslinker in combination with the other components of the multi-component adhesive composition.

[0042] The preparation of suitable UDMA is known to the person skilled in the art and is shown schematically in the following Scheme 1: Scheme 1 :

[0043] MOI TOI CHMDI

[0044] A particularly preferred crosslinker is shown in the following formula 1:

[0045] formula 1

[0046] 7,7,9-(or 7,9,9-)trimethyl-4,13-dioxo-3,14-dioxa-5,12-diaza-hexadecane-1,16-diol dimethacrylate

[0047] In a preferred embodiment, the amount of UDMA is 20 to 80 wt.% or 35 to 80 wt.%, more preferably from 35 to 70 wt.%, especially preferably from 40 to 55 wt.%, in each case based on the total weight of component A. In a further preferred embodiment, the UDMA is present in an amount of at least 50 wt.%, in particular at least 65 wt.%, especially at least 75 wt.%, in particular at least 80 wt.%, in each case based on the total weight of the crosslinkers.

[0048] In a preferred embodiment of the multi-component adhesive composition, component A contains a crosslinker with n>2, where n corresponds to the polymerizable groups of the crosslinker. The crosslinkers are preferably selected from triethylene glycol dimethacrylate (TEDMA), UDMA, diethylene glycol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, butanediol di(meth)acrylate, 1,10-decanediol di(meth)acrylate, 1,12-dodecanediol di(meth)acrylate, and mixtures thereof. Other possible crosslinkers are familiar to the person skilled in the art and can be found in the prior art.

[0049] Further examples of crosslinkers are selected from the group consisting of diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, butylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 1,3-butanediol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, trimethylolethane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, trimethylolmethane tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, polybutylene glycol di(meth)acrylate, bisphenol A diglycidyl (meth)acrylate, di-2-(meth)acryloyloxyethyl 2,2,4-trimethylhexamethylene dicarbamate, l,3,5-tris[l,3-bis{(meth)acryloyloxy}-2-propoxycarbonylaminohexane] -l,3,5-(lH,3H,5H)triazine-2,4, 6-trione, 2,2-bis[4-(3-(meth)acryloyloxy-2-hydroxypropyl)phenyl]propane, N,N'-(2,2,4-trimethyl- hexamethylene)bis[2-(aminocarboxy)propane-1,3-diol]tetramethacrylate and the like.Two or more (meth)acrylate-based crosslinkers free of an acid group can be used in combination. Among them, 2-hydroxy-1,3-di(meth)acryloyloxypropane, di-2-(meth)acryloyloxyethyl 2,2,4-trimethylhexamethylene dicarbamate, ethylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, and UDMA are preferably used in view of the mechanical strength of the cured product of the dental polymerizable composition of the present embodiment.

[0050] It has been surprisingly shown that the use of UDMA, especially in combination with the other components, especially the fillers, leads to a desired pasty, spreadable consistency. In a further embodiment, the crosslinker Ai) is selected from the group consisting of 1,14-tetradecane dimethacrylate, dimethylol tricyclodecane diacrylate, glycerol diacrylate, glycerol triacrylate, ethylene glycol diacrylate, diethylene glycol diacrylate, triethylene glycol dimethacrylate, tetraethylene glycol di(meth)acrylate, 1,3-propanediol diacrylate, 1,3-propanediol dimethacrylate, trimethylolpropane tri(meth)acrylate, 1,2,4-butan- triotrimethacrylate, 1,4-cyclohexanediol diacrylate, 1,4-cyclohexanediol dimethacrylate, 1,6-hexanediol di(meth)acrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, pentaerythritol tetramethacrylate, Sorbitol hexacrylate, 2,2-bis[4-{2-hydroxy-3-acryloyloxypropoxy)phenyl]propane and 2,2-bis[4-(2-hydroxy-3-methacryloyioxypropoxy)phenyl]propane (Bis-GMA).

[0051] In a preferred embodiment, component A comprises at least two crosslinkers, in particular UDMA and triethylene glycol dimethacrylate (TEDMA). Component A particularly preferably comprises the crosslinkers UDMA and TEDMA in a weight ratio of UDMA to TEDMA of 20:1 to 1:1, preferably 15:1 to 2:1, further preferably 12:1 to 5:1, in particular 10:1 to 6:1.

[0052] Component A further comprises at least 0.5% by weight, preferably 5% by weight, of a further polymerizable (meth)acrylate-based constituent (hereinafter also A-ii)). Ai) and A-ii) differ chemically from one another. A-ii) is a polymerizable (meth)acrylate-based constituent. Polymerizable (meth)acrylate-based constituents are preferably mono- or multifunctional monomers with one or more polymerizable (meth)acrylate functions. A-ii) is preferably a radically polymerizable monomer. A-ii) is particularly preferably selected from radically polymerizable monomers with at least one mono- or at least 2 or at least 3 methacrylate groups.Preferred mono- or multifunctional (meth)acrylates are methyl, ethyl, 2-hydroxyethyl, butyl, benzyl, tetrahydrofurfuryl or isobornyl (meth)acrylate, p-cumylphenoxyethylene glycol methacrylate (CMP-1E), 2-(2-biphenyloxy)ethyl methacrylate, bisphenol A dimethacrylate, Bis-GMA (an addition product of methacrylic acid and bisphenol a diglycidyl ether), ethoxylated or propoxylated bisphenol A dimethacrylate, such as2-[4-(2-methacryloyloxyethoxyethoxy)phenyl]-2-[4-(2-methacryloyloxyethoxy)phenyl]propane) (SR-348c, Sartomer; contains 3 ethoxy groups) and 2,2-bis[4-(2-methacryloxypropoxy)phenyl]propane, V-380 (an addition product of a mixture of 0.7 mol of 2-hydroxyethyl methacrylate and 0.3 mol of 2-hydroxypropyl methacrylate with 1 mol of a,a,a',a'-tetramethyl-m-xylylene diisocyanate), di-, tri- or tetraethylene glycol dimethacrylate, trimethylolpropane trimethacrylate, pentaerythritol tetramethacrylate as well as glycerol di- and trimethacrylate, 1,4-butanediol dimethacrylate, 1,10-decanediol dimethacrylate (D3MA), Bis(methacryloyloxymethyl)tricyclo-[5.2.1.02,6]decane (DCP), polyethylene glycol or polypropylene glycol dimethacrylates, such as polyethylene glycol-200 or polyethylene glycol-400 dimethacrylate (PEG-200 or PEG-400-DMA) or 1,12-dodecanediol dimethacrylate, or a mixture thereof.Particularly preferred monomers are methyl methacrylate, triethylene glycol dimethacrylate and hydroxyethyl methacrylate (HEMA).

[0053] In a preferred embodiment, MMA can be used for bonding the plastics and for dilution. A preferred range for the use of MMA is 0 to 15 wt.% or 0.5 to 12 wt.%, particularly preferably 5 to 10 wt.%, based in each case on the total weight of component A.

[0054] Furthermore, in a preferred embodiment, HEMA can be used to stabilize a thiourea derivative and to stabilize the pigments. Preferred application ranges are 1 to 10 wt.%, especially 2 to 10 wt.% or 5 to 10 wt.%, each based on the total weight of component A.

[0055] Particularly preferably, A-ii) is a monomer having a (meth)acrylate group. A-ii is preferably selected from the group consisting of cyclohexyl (meth)acrylate, 4-tert-butylcyclohexyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, 2-phenoxyethyl (meth)acrylate, allyl acrylate, isobornyl (meth)acrylate, stearyl (meth)acrylate, phenoxybenzyl (meth)acrylate, o-phenylphenolethyl (meth)acrylate, Ethyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, hydroxypropyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, glycidyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypro- pyl(meth)acrylate, 2-methoxyethyl(meth)acrylate, 2-Ethoxyethyl (meth)acrylate, 2-methylhexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate and benzyl (meth)acrylate.

[0056] Particularly preferably, A-ii) comprises a C12-C16 methacrylic acid ester and / or 3,3,5 trimethyl cyclohexanol methacrylate (TMCHMA).

[0057] Component A also contains at least 15% by weight of fillers (hereinafter also referred to as A-iii)), whereby the weight is based on the total weight of component A.

[0058] Component A comprises, in particular, organic fillers and / or inorganic fillers, which may be surface-functionalized. Preferred inorganic fillers are oxides, such as SiO2 and ZrO2, or mixed oxides of SiO2, ZrO2, and / or ZnO, nanoparticulate or microfine fillers, such as fumed silica or precipitated silica. Particularly preferred fillers are acrylate-functionalized SiO2 and silanized SiO2. Depending on the surface functionalization and specific surface area, these have various functions, such as thickening the filler composition to achieve the desired pasty consistency and increasing the crosslinking rate and abrasion stability. Preferred ranges for the fillers are 5 to 80 wt.% or 10 to 80 wt.% or 15 to 75 wt.%, particularly preferred are 15 to 50 wt.% and 15 to 30 wt.%, each based on the total weight of component A.

[0059] In a further preferred embodiment of the multi-component adhesive composition, component A may contain a prepolymer and / or organic fillers. These may consist, for example, of methyl methacrylate, hydroxyethyl methacrylate, triethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, UDMA, or bisphenol glycdiyl methacrylate, as well as mixtures thereof.

[0060] Furthermore, a preferred embodiment is characterized in that the inorganic fillers in component A of the multi-component adhesive composition are surface-functionalized. This serves to improve the bond between the filler particles and the crosslinked polymerization matrix. Preferred surface functionalizations are functionalized silica particles, particularly preferably (meth)acrylate or silazated silica particles. These are structurally modified silicas that have been post-treated with hexamethyldisilazane, with a specific surface area in the range of 100-200 m². 2 / g, but preferably 120-190 m 2 / g, and a carbon content of 1-5 wt.% based on the total weight of the silica, is particularly preferred. Another particularly preferred silica is methacrylsilane-treated fumed silica, which has a specific surface area in the range of approximately 10-100 m 2 / g, but preferably 20-50 m2 / g, and a carbon content of 0.5-5 wt.% based on the total weight of the silica. The functional groups on the surface ensure rapid crosslinking. They also serve to adjust the rheology. The HMDS-functionalized inorganic filler is preferably a filler described as "low-thickening." Due to the HDMS functionalization, it remains in the dispersion and bonds well with the polymer matrix. However, it does not actively intervene in the polymerization process and ensures a higher filler content without excessive thickening. Thus, the use of differently thickening and differently functionalized fillers can influence both the rheology and the crosslinking behavior. According to the invention, the inorganic fillers used are intended to achieve the desired pasty consistency and increase the hardness and abrasion resistance of the material.

[0061] Component A optionally further comprises color pigment (hereinafter also A-iv)). According to the invention, this preferably makes up at least 5 wt.% based on the total weight of component A. In an alternative embodiment, it is also possible to provide the pigments separately and add them to the multi-component adhesive composition.

[0062] In a further preferred embodiment, component A comprises color pigments, in particular inorganic and / or organic color pigments. Commonly used color pigments include titanium oxide, Indian blue, or iron oxides. Other color pigments are known to those skilled in the art and can also be used. In a preferred embodiment, the color pigment mixture can also be added later as a premix to the multi-component adhesive composition. Furthermore, the preferred color pigment mixture can comprise inorganic fillers and / or acrylates. Dispersing aids, such as Disperbyk, can also be used.

[0063] Furthermore, inorganic pigments are particularly preferred because they are chemically more stable, less susceptible to fading and have high opacity.

[0064] In a preferred embodiment, component A comprises one or more color pigments in an amount of 1 to 25 wt.%, preferably 5 to 20 wt.%, more preferably 8 to 20 wt.% or 10 to 20 wt.%, particularly preferably 10 to 16 wt.% or 8 to 18 wt.%, in each case based on the total weight of component A.

[0065] In a further preferred embodiment, the component comprises at least 3, preferably at least 4, in particular at least 5 chemically different pigments. Furthermore, component A can optionally contain at least 1 wt.% of a polymerizable component having at least one OH group and / or an -NR / R 2 Group, where R 1 and R 2, each independently selected from the group consisting of H, C1-C8-alkyl and C5-C8-cycloalkyl (hereinafter also Av)), such as HEMA. Av) differs chemically from Ai) and A-ii). The component Av is radically polymerizable. Examples of radically polymerizable monomers bearing amino groups are 2-dimethylaminoethyl methacrylate or 2-methylaminoethyl methacrylate. A radically polymerizable component with at least one -NR X R 2 Group, where R 1 and R 2 , are each independently selected from the group consisting of H, C1-C6-alkyl and C3-C6-cycloalkyl, are preferably those which also contain a (meth)acrylate group. The substituent R 1 and R 2 is preferably independently selected from methyl, ethyl, propyl, i-propyl, butyl, i-butyl, tert-butyl, pentyl and hexyl.

[0066] Av is preferably present in an amount of 0.2 to 8 wt.%, particularly preferably in an amount of 0.5 to 6 wt.% and especially in an amount of 0.8 or at least 1 wt.% to 4 or 5 wt.%, in each case based on the total weight of component A.

[0067] Furthermore, other dispersing agents available on the market, such as DISPERBYK®, can be used.

[0068] Component A preferably also contains at least 0.5 wt.% of a thiourea derivative (hereinafter also A-vi)). Its use has been shown to have a particularly beneficial effect on polymerization behavior.

[0069] Suitable examples are N-benzoylthiourea. Further preferred thiourea derivatives are selected from the group consisting of ethylenethiourea, N-methylthiourea, N-ethylthiourea, N-propylthiourea, N-butylthiourea, N-laurylthiourea, N-phenylthiourea, N-cyclohexylthiourea, N,N-dimethylthiourea, N,N-diethylthiourea, N,N-dipropylthiourea, N,N-dibutylthiourea, N,N-dilaurylthiourea, N,N-diphenylthiourea, N,N-dicyclohexylthiourea, trimethylthiourea, tetramethylthiourea, N-acetylthiourea, N-benzoylthiourea, l-Allyl-3-(2-hydroxyethyl)-2-thiourea, l-(2-tetrahydrofurfuryl)-2-thiourea, N-tert-butyl-N'-isopropylthiourea, 2-pyridylthiourea, and the like. Two or more types of thiourea derivatives can be used in combination.Among them, N-benzoylthiourea is preferably used in view of the curability of the dental polymerizable composition of the present embodiment.

[0070] Particularly suitable are also 2,3-difluorophenyl)thiourea and / or N-allylthiourea and / or benzoylthiourea, which provide particularly positive results with regard to polymerizability.

[0071] The thiourea derivative can also be present as a mixture of two or more thiourea derivatives. The thiourea derivative is preferably present in an amount of 0.5 to 5 wt.%, preferably 0.6 to 3 wt.%, in particular 0.8 to 2.5 wt.%, for example 1.1 to 2.0 wt.%, based in each case on the total weight of component A.

[0072] Component A preferably further comprises a transition metal catalyst (hereinafter also A-vii). This is typically present in an amount of less than 1 wt. %, based on the total weight of component A. Particularly preferred catalysts are selected from copper or vanadium acetate, 2-ethylhexanoate, laurate, acetylacetonate, or other common carboxylic acid ligands known to the person skilled in the art.

[0073] In a preferred embodiment, the multi-component adhesive composition also comprises one or more copper and / or vanadium compounds within component A, wherein the amount of these compounds amounts to at most 1 wt.% of the total weight of component A. These transition metal compounds are preferably transition metal catalysts used to increase the polymerization rate.

[0074] Particularly preferred catalysts are selected from copper or vanadium acetate, 2-ethylhexanoate, laurate, acetylacetonate, or other common carboxylic acid ligands known to the person skilled in the art.

[0075] Copper ethylhexanoate is especially preferred.

[0076] Component A-vii) is preferably present in an amount of 0.001 to 0.5 wt.%, particularly preferably 0.005 to 0.1 wt.% and in particular 0.008 to 0.05 wt.%, in each case based on the total weight of component A.

[0077] Furthermore, component A may comprise one or more photoinitiators (hereinafter also A-viii)). Further examples of photopolymerization initiators according to A-viii) are selected from the group consisting of phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine, benzyl ketal, diacetyl ketal, benzyldimethyl ketal, benzyldiethyl ketal, benzylbis(2-methoxyethyl) ketal, 4,4'-dimethyl (benzyldimethyl ketal), anthraquinone, 1-chloroanthraquinone, 2-chloroanthraquinone, 1,2-benzanthraquinone, 1-hydroxyanthraquinone, 1-methylanthraquinone, 2-ethylanthraquinone, 1-bromoanthraquinone, thio2-methylthioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2,4-diisopropylthioxanthone, 2-Chloro-7-trifluoromethylthioxanthone, thioxanthone 10,10-dioxide, thioxanthone 10-oxide, benzoin methyl ether, benzoin ethyl ether, benzoin isopyl ether, benzoin isobutyl ether, benzophenone, bis(4-dimethylaminophenyl) ketone, 4,4'-bis(diethylamino)benzophenone and the like.Two or more types of photopolymerization initiators can be used in combination.

[0078] Particularly preferred initiators are selected from the group consisting of phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide, 2-hydroxy-2-methyl propiophenone, 1-hydroxycyclohexyl phenyl ketone, ethyl(3-benzoyl-2,4,6-trimethylbenzoyl)(phenyl)phosphinate.

[0079] It has surprisingly been found that, for the present invention, a higher amount of one or more photoinitiators is advantageous for the polymerization. Preferably, two or more photoinitiators are used.

[0080] The preferred amount of photoinitiator(s) is 1 to 16 wt.%, particularly preferably 4 to 15 wt.%, in particular 6 to 14 wt.%, especially 8 or 10 to 13 wt.%, in each case based on the total weight of component A.

[0081] The photoinitiator particularly preferably comprises a mixture of phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide and 2-hydroxy-2-methylpropiophenone, in particular in a weight ratio of phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide to 2-hydroxy-2-methylpropiophenone of 1:10 to 1:1, in particular 1:5 to 1:2, especially 1:4 to 1:2.5.

[0082] The multi-component adhesive composition of the present invention comprises at least one further component B, which is spatially separated from component A. The multi-component adhesive composition according to the invention contains component B, which preferably comprises methyl methacrylate (MMA), which serves to improve the adhesive bond of the plastics and to dilute them.

[0083] Component B preferably comprises MMA (hereinafter also Bi)) in an amount of up to 60 wt.% and particularly preferably from 5 to 40 wt.% based on the total weight of component B.

[0084] Component B further preferably contains at least 30% by weight, based on the total weight of component B, of one or more mono- or multifunctional (meth)acrylate monomers (hereinafter also B-ii)), for example triethylene glycol dimethacrylate, diethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, ethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, butanediol dimethacrylate, hexanediol dimethacrylate, decanediol dimethacrylate, dodecanediol dimethacrylate, bisphenol A dimethacrylate, trimethylolpropane trimethacrylate, ethoxylated bisphenol A dimethacrylate, but also bis-GMA (2,2-bis-4-(3-methacryloxy-2-hydroxypropyl)phenylpropane) and the reaction products of isocyanates, in particular di- and / or triisocyanates and OH-group-containing methacrylates.In a particularly preferred embodiment, one or more at least bifunctional monomers are selected from diethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, ethylene glycol dimethacrylate, and / or mixtures thereof. Bi) and B-ii) differ chemically from one another.

[0085] Preferably, the components used as B-ii) are those already listed above under Ai) and A-ii). B-ii particularly preferably comprises a mixture of triethylene glycol dimethacrylate and UDMA.

[0086] B-ii is preferably present in an amount of 30 to 70 wt.%, particularly preferably 45 to 65 wt.%, in each case based on the total weight of component B.

[0087] Furthermore, component B comprises at least 15 wt. %, based on the total weight of component B, of (in)organic fillers. These are preferably selected from the same substances as already described above for (A-iii)) and have the same function. The fillers are preferably present in an amount of 15-70 wt. %, particularly preferably from 20 to 55 wt. %, in each case based on the total weight of component B. Furthermore, component B comprises one or more free radical initiators, preferably hydroperoxide initiators, in particular cumene hydroperoxide (hereinafter also B-iv). Also preferred are organic peroxides, which are preferably selected from the group consisting of benzoyl peroxide, cumene hydroperoxide, t-butyl hydroperoxide, t-amyl hydroperoxide, 1,1,3,3-tetramethylbutyl hydroperoxide, 2,5-dimethyl-2,5-di(hydroperoxy)hexane, p-diisopropylbenzene, monohydroperoxide, p-methane hydroperoxide, pinane hydroperoxide and the like.Two or more types of organic peroxides can be used in combination. Among them, cumene hydroperoxide is preferably used in view of the curability of the dental polymerizable composition of the present embodiment.

[0088] The radical initiators (B-iv) are preferably present in an amount below 4 wt.%, in particular in the range from 0.1 to 3 wt.%, especially from 0.5 to 2 wt.%.

[0089] Other photoinitiators or radical initiators are also possible, preferably selected from champherquinone, benzoin methyl ether, 2-hydroxy-2-methyl-l-phenyl-l-propanone, diphenyl-2,4,6-trimethylbenzoylphosphine oxide, benzoin methyl ether, benzophenone, 9,10-anthraquinone, and derivatives thereof. Furthermore, the initiator can be selected from benzoyl peroxide, 2-butanone peroxide, lauroyl peroxide, and tert-butyl peroxide. Other initiators are known to the person skilled in the art and are also possible.

[0090] In a further preferred embodiment, component A in the multi-component adhesive composition according to the invention contains methyl methacrylate. This serves primarily to bond the plastics.

[0091] In a further preferred embodiment, the multi-component adhesive composition contains one or more photoinitiators in either component A and / or component B. Photoinitiators or radical initiators are preferably selected from champferquinone, benzoin methyl ether, 2-hydroxy-2-methyl-1-phenyl-1-propanone, diphenyl 2,4,6-trimethylbenzoylphosphine oxide, benzoin ethyl ether, benzophenone, 9,10-anthraquinone, and derivatives thereof. Other photoinitiators are known to the person skilled in the art and are also possible. In a further preferred embodiment, component A of the multi-component adhesive contains a dispersion stabilizer. Dispersants are also known to the person skilled in the art, for example, under the terms emulsifiers, protective colloids, wetting agents, detergents, etc.

[0092] In a further preferred embodiment, the multi-component adhesive composition contains a prepolymer and / or organic fillers in component B.

[0093] Component A and / or component B preferably contain polymerization inhibitors which stabilize the polymerization mixtures.

[0094] Examples of polymerization inhibitors include dibutylhydroxytoluene, 6-tert-butyl-2,4-xylenol, 2,6-di-tert-butyl-p-cresol, 2,6-di-tert-butyl-4-methylphenol (BHT), and the like. Two or more types of polymerization inhibitors can be used in combination.

[0095] Components A and B are spatially separated from each other and are each produced by mixing their individual components. Before the bonding process, components A and B are combined and mixed.

[0096] The weight ratio of component A to component B is usually 10:1 to 1:10, preferably 5:1 to 1:5, in particular 2:1 to 1:2 and especially 1.5:1 to 1:1.5.

[0097] The viscosity of component A is preferably in the range from 1 to 100 Pas, particularly preferably in the range from 3 to 80 Pas, especially in the range from 4 to 75 or 5 to 35, for example 5 to 25 Pas.

[0098] The viscosity of component A is preferably in the range from 1 to 100 Pas, particularly preferably in the range from 3 to 80 Pas, especially in the range from 4 to 75 or 5 to 35, for example 5 to 25 Pas.

[0099] The viscosities were determined using an Anton Paar Physica MCR101 rheometer, PP25 measuring system; measuring gap d = 0.1 mm, measuring temperature 23°C, shear rate d(gamma) = 100 1 / s, measuring point duration 10 s.

[0100] In a preferred embodiment, component A and / or B is thixotropic. The invention also provides a method for producing dental restorations. This comprises at least the following steps: a) providing a fixing element, b) providing an anatomically shaped restoration part with a gingiva / tooth-colored portion, c) bonding the fixing element to the anatomically shaped restoration part, characterized in that the bonding takes place with an adhesive, wherein the adhesive corresponds to the multi-component adhesive composition according to the invention, and the adhesive both creates the bond between the fixing element and the restoration part and covers the color of the fixing element and adapts it to the color of the restoration part.

[0101] The method according to the invention is described below, whereby only the essential points are listed here and further points can be added.

[0102] First, the individual components of the dental restoration are designed using suitable CAD software and configured so that they can be assembled without undercuts. The gingiva is fabricated from only one piece per saddle. The manual work is then limited to applying a primer, if necessary, to the fixation elements, also known as the (tooth) framework, and bonding them to the tooth or gingival portions. An inventive opaque (pink or tooth-colored) adhesive, corresponding to the multi-component adhesive composition, opaques the framework and bonds the fixation elements to the tooth or gingival structures in a single step, with the tooth elements being bonded from above and the gingival elements being bonded from below.The framework is preferably designed so that it is free of undercuts and has a defined insertion direction in the direction of the element that defines the teeth (occlusal / incisal direction), and also free of undercuts and has a defined insertion direction in the direction of the element that reproduces the mucous membrane (basal direction). The insertion directions can vary. Thus, the essential points of the invention can be summarized below:

[0103] - Production of the scaffolding

[0104] - Production of the gingival part

[0105] - Fabrication of the tooth portion - Preparation of the framework (possibly corundum blasting, application of primer)

[0106] - Preparation of the gingival part (possibly corundum blasting, application of primer)

[0107] - Preparation of the tooth elements (possibly corundum blasting)

[0108] - Manufacturing and preconditioning of the prosthetic components

[0109] - Joining the individual components, whereby the multi-component adhesive both creates the connection and ensures opacity and

[0110] - Mixing of the adhesive (depending on the construction, opaque tooth-colored) for fixing tooth elements and gingival part

[0111] - Joining the gingival part and the tooth elements

[0112] - Removal of any excess adhesive

[0113] - Mixing the pink opaque glue

[0114] - Application of the pink opaque adhesive to the framework and / or gingival part

[0115] - Joining the framework and the gingival part

[0116] - Removal of any excess pink opaque adhesive

[0117] - Curing of the two adhesives

[0118] - Final processing of the restoration, polishing.

[0119] A further subject of the present invention is a method for producing a dental prosthesis comprising the following steps: a) manufacturing and preconditioning the prosthesis components, b) joining the individual components, wherein in at least one step an opacity and simultaneous joining by means of the multi-component adhesive according to the present invention takes place.

[0120] The methods of the present invention significantly reduce processing because the gingival structures can be prepared in advance. Processing, particularly manual work, is limited to assembling and securing the elements. A key advantage of the present invention is that the adhesive has an opaque effect. Due to the advantageous use of MMA in the formulation, only the securing elements require chemical pretreatment. The formulation for the multi-component adhesive is stable, pasty, and easy to spread. Thus, in the method according to the invention, production can be designed so that only three elements per saddle need to be connected. Furthermore, the invention provides a dosing device for applying the multi-component adhesive.The dosing device for applying a multi-component adhesive composition is characterized in that (a) the multi-component adhesive composition comprises at least a first component A and a second component B, component A comprises at least the following: i. at least 35% by weight of a crosslinker, preferably urethane dimethacrylate (UDMA), ii. at least 5% by weight of a polymerizable component based on (meth)acrylate, iii. at least 15% by weight of fillers, preferably organic fillers and / or inorganic fillers, which are optionally surface-functionalized, iv. optionally at least 0.5% by weight, preferably 5 to 20% by weight, particularly preferably 8 to 18% by weight, in particular 10 to 16% by weight of color pigments, v. optionally at least 1% by weight of a polymerizable component having at least one OH group and / or one -NR / R. 2 Group, where R 1 and R 2, are each independently selected from the group consisting of H, C 1 -C 8 alkyl and C 5 -C 8 cycloalkyl, vi. at least 0.5 wt.% of a thiourea derivative vii. less than 1 wt.% of a transition metal-based catalyst viii. optionally one or more photoinitiator(s), preferably in an amount of at least 0.5 wt.%, more preferably from 2 to 14 wt.%, in particular 4 to 12 wt.% or 6 to 12 wt.%, wherein the weight data are in each case based on the total weight of component A and wherein component B comprises at least the following: i. optionally methyl methacrylate, ii. at least 30 wt.% of one or more mono- or multifunctional (meth)acrylate monomers, iii. at least 15 wt.% (in)organic fillers, iv. one or more hydroperoxide initiators, in particular cumene hydroperoxide, wherein the weight data are in each case based on the total weight of component B; and (b) the dosing device has a chamber for each component.In a further preferred embodiment, the dosing device is characterized in that it comprises two chambers, so that the multi-component adhesive composition comprises the at least two components A and B, component A in the first chamber and component B in the second chamber.

[0121] The following embodiments demonstrate the present invention and do not limit the subject matter of the invention thereto.

[0122] 1. Example composition for component A of the multi-component adhesive composition:

[0123] To produce the example formulations for component A and component B listed in Table 1 and Table 2, the individual components are mixed together.

[0124] Two-component adhesives are manufactured by filling component A separately from component B in a two-chamber dosing device. The combinations of A0 with each of B1 to B3, A1 with each of B1 to B3, A2 with each of B1 to B3, A3 with each of B1 to B3, and A4 with each of B1 to B3 are tested. Before the bonding process, component A is mixed with component B in the two-chamber dosing device by combining the two components. All mixtures demonstrated excellent opacity and very good adhesive behavior, so that the manual labor required to manufacture the prostheses could be significantly reduced.

[0125] Table 1 : Example formulations for component A

[0126]

[0127]

[0128] Table 2: Example formulations for component B

[0129] Table 3: Information on the ingredients used

[0130]

[0131]

Claims

Patent claims 1. Multi-component adhesive composition for use in the production of dental restorations, comprising at least a first component A and a second component B, component A comprising at least the following: i. at least 35% by weight of a crosslinker, preferably urethane dimethacrylate (UDMA), ii. at least 5% by weight of a polymerizable component based on (meth)acrylate, iii. at least 15% by weight of fillers, preferably organic fillers and / or inorganic fillers, which are optionally surface-functionalized, iv. optionally at least 0.5% by weight, preferably 5 to 20% by weight, particularly preferably 8 to 18% by weight, in particular 10 to 16% by weight of color pigments, v. optionally at least 1% by weight of a polymerizable component having at least one OH group and / or an -NR / R 2 Group, where R 1 and R 2, are each independently selected from the group consisting of H, C1-C6-alkyl and C5-C6-cycloalkyl, vi. at least 0.5 wt.% of a thiourea derivative vii. less than 1 wt.% of a transition metal-based catalyst viii. optionally one or more photoinitiator(s), preferably in an amount of at least 0.5 wt.%, more preferably from 2 to 14 wt.%, in particular 4 to 12 wt.% or 6 to 12 wt.%, wherein the weight data are in each case based on the total weight of component A and wherein component B comprises at least the following: i. optionally methyl methacrylate, ii. at least 30 wt.% of one or more mono- or multifunctional (meth)acrylate monomers, iii. at least 15 wt.% (in)organic fillers, iv. one or more hydroperoxide initiators, in particular cumene hydroperoxide, the weights being based on the total weight of component B.

2. Multi-component adhesive composition according to claim 1, characterized in that component A contains one or more crosslinkers with n>2, where n corresponds to the polymerizable groups of the crosslinker.

3. The multi-component adhesive composition according to at least one or more of claims 1 to 2, characterized in that component A contains methyl methacrylate.

4. The multi-component adhesive composition according to at least one or more of claims 1 to 3, characterized in that component A and / or component B contains one or more photoinitiators.

5. Multi-component adhesive composition according to at least one or more of claims 1 to 4, characterized in that component A contains a prepolymer and / or organic fillers.

6. Multi-component adhesive composition according to at least one or more of claims 1 to 5, characterized in that the inorganic fillers in component A are surface-functionalized.

7. Multi-component adhesive composition according to at least one or more of claims 1 to 6, characterized in that the color pigments in component A are inorganic and / or organic color pigments.

8. The multi-component adhesive composition according to at least one or more of claims 1 to 7, characterized in that the components contain one or more dispersion stabilizers.

9. Multi-component adhesive composition according to at least one or more of claims 1 to 8, characterized in that component A contains one or more copper and / or vanadium compounds, these constituting at most 1 wt.% of the total weight of component A 10. Multi-component adhesive composition according to at least one or more of claims 1 to 9, characterized in that component B contains a prepolymer and / or organic fillers.

11. A method for producing dental restorations, comprising the following steps: a) providing a fixing element, b) providing an anatomically shaped restoration part with a gingiva / tooth-colored portion, c) bonding the fixing element to the anatomically shaped restoration part, characterized in that the bonding takes place with an adhesive, wherein the adhesive corresponds to the multi-component adhesive composition preferably according to at least one or more of claims 1 to 10, and the adhesive both creates the bond between the fixing element and the restoration part and covers the color of the fixing element and adapts it to the color of the restoration part.

12. A method for producing dental restorations according to claim 11, wherein the fixing element is preferably designed such that it is designed in the direction of the element that defines the teeth (in the occlusal / incisal direction) without undercuts with a defined insertion direction and that it is The direction of the element that reproduces the mucous membrane (in the basal direction) is also designed without undercuts and with a defined insertion direction.

13. Dosing device for applying a multi-component adhesive composition, characterized in that (a) the multi-component adhesive composition comprises at least a first component A and a second component B, wherein Component A comprises at least the following: i. at least 35% by weight of a crosslinker, preferably urethane dimethacrylate (UDMA), ii. at least 5% by weight of a polymerizable component based on (meth)acrylate, iii. at least 15% by weight of fillers, preferably organic fillers and / or inorganic fillers, which are optionally surface-functionalized, iv. optionally at least 0.5% by weight, preferably 5 to 20% by weight, particularly preferably 8 to 18% by weight, in particular 10 to 16% by weight of color pigments, v. optionally at least 1% by weight of a polymerizable component having at least one OH group and / or one -NR X R 2 Group, where R 1 and R 2, are each independently selected from the group consisting of H, C1-C6-alkyl and C5-C6-cycloalkyl, vi. at least 0.5 wt.% of a thiourea derivative vii. less than 1 wt.% of a transition metal-based catalyst viii. optionally one or more photoinitiator(s), preferably in an amount of at least 0.5 wt.%, more preferably from 2 to 14 wt.%, in particular 4 to 12 wt.% or 6 to 12 wt.%, wherein the weight data are in each case based on the total weight of component A and wherein component B comprises at least the following: i. optionally methyl methacrylate, ii. at least 30% by weight of one or more mono- or multifunctional (meth)acrylate monomers, iii. at least 15% by weight of (in)organic fillers, iv. one or more hydroperoxide initiators, in particular cumene hydroperoxide, the weights being based in each case on the total weight of component B; and (b) the dosing device has a chamber for each component.

14. Dosing device according to claim 13 which comprises two chambers, characterized in that the multi-component adhesive composition comprises the two components A and B, wherein the first chamber contains component A and the second chamber contains component B.

15. A method for producing a dental prosthesis comprising the following steps: a) manufacturing and preconditioning the prosthesis components, b) joining the individual components, wherein in at least one step an opaque coating and simultaneous joining by means of the multi-component adhesive according to one of the preceding claims takes place.

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