Hardenable X-ray visible material

Description

[0001] The present invention relates to a curable and radiopaque material, a material producible therefrom by polymerization, a process for producing the curable material and the cured material, and the use of the curable material and the cured material, respectively. The curable material and the cured material can be used, inter alia, in orthopedics as so-called bone cement, but in particular as a dental filling material, dental cement, dental base material, flowable composite material (flowable material), crown and bridge material, for the fabrication of inlays, onlays, and core build-up materials, as well as in radiographic diagnostics as a surgical guide. Furthermore, the present invention relates to the use of the curable material more generally as a construction material in an additive manufacturing process using a digital data model.

[0002] Over the past few decades, a wide range of applications for curable (radiopaque) materials have been developed in modern medicine, for example in orthopedics and dentistry. Bone cements and filling or restorative materials are just a few representative examples. These materials are based on organic polymers, with the bone cement mixture containing polymerizable monomers and an initiator and / or activator to trigger polymerization, resulting in hardening via cold polymerization.

[0003] For example, a widely used organic bone cement is based on polymethyl methacrylate (PMMA), which is obtained by polymerizing the monomer methyl methacrylate (MMA). Commercial PMMA bone cements are offered as two-component systems that need to be mixed.

[0004] In orthopedic and especially dental practice, it is often crucial to be able to clearly distinguish non-natural (i.e., artificial) material from previously treated bone or tooth from the remaining natural bone or tooth material. Such a distinction is made possible, for example, by a radiographic examination. X-rays can be used, for instance, to detect marginal gaps during filling therapy. In particular, this enables the dentist to identify even small marginal gaps between a composite filling (as an example of a non-natural or artificial dental material) and the surrounding natural tooth material and—if necessary—to excavate them precisely.For this to be effective, however, the filling composite (and, more generally, artificial materials used in osteosynthesis alongside dental materials) must possess sufficiently high radiopacity to absorb X-rays adequately during the X-ray examination. This absorption provides the necessary contrast in an X-ray image, ultimately allowing differentiation between natural tooth structure and the filling composite (or artificial dental material). The filling composite (or, more generally, bone or tooth components made of artificial dental material) is typically identifiable in an X-ray image by its lower degree of blackness. Sufficient radiopacity of the artificial dental material thus very often allows for a reliable distinction between artificial dental material and natural bone or tooth structure.

[0005] The natural radiopacity of a human tooth is typically 2 mm of aluminum (Al) or less (dentin approx. 1.5 mm Al, enamel approx. 2 mm Al). Therefore, a radiopaque, artificial dental material should generally have a value greater than 2.5 mm Al. For example, a value of 10 mm Al means that a 1 mm thick specimen of radiopaque, artificial, hardened dental material will produce an effect on an X-ray film identical to that produced by a 10 mm thick aluminum specimen.

[0006] Particularly preferred radiopaque values ​​lie in the range between 3.0 and 5.0 mm Al. The higher the radiopaque value of an artificial dental material (e.g., a composite filling), the better it can be distinguished from natural tooth structure in an X-ray image. A well-known, but also controversial, suitable artificial dental material is amalgam, whose radiopaque value can exceed 10 mm aluminum (Al).

[0007] Significant progress has been made in the field of X-ray diagnostics in recent years, allowing for an increasingly precise differentiation between artificial osteosynthetic material or dental material and surrounding natural materials.

[0008] In recent years, a procedure known as digital volume tomography (DVT) has become particularly established in dental practices. A DVT device essentially consists of an X-ray source and an opposing detector (e.g., a flat-panel detector). During DVT, the object being examined is penetrated by a cone-shaped or pyramidal, usually pulsed, X-ray beam (X-ray flash). This is why the term CBCT (cone beam computed tomography) has become common in English-speaking countries. On the side opposite the X-ray source, the signals attenuated by the object being examined are detected as a two-dimensional projection on the detector. During the examination, the unit consisting of the X-ray source and detector (gantry) rotates around the object being examined to acquire numerous individual images. In each individual image, attenuated grayscale X-ray images are obtained as a 2D projection.From these individual images, a three-dimensional reconstruction (grayscale coordinate image, volumetric graphic) is calculated using back projection, which depicts the anatomical structures of the object under investigation in the form of voxels of different grayscale levels. The resulting three-dimensional reconstruction can be viewed either as individual, two-dimensional cross-sectional images (tomograms) or in a 3D view.

[0009] CBCT-generated images have proven particularly advantageous in dental implantology. They allow for especially precise planning of implants and their placement, taking into account the available bone volume. CBCT-generated images have also proven highly reliable in locating wisdom teeth in preparation for surgical procedures.

[0010] For example, the use of barium-containing glasses or poorly soluble ytterbium fluoride particles for X-ray contrasting of highly viscous composite materials - such as those used as dental filling / restoration material - is known from the state of the art.

[0011] German patent application DE 24 46 547 A1 discloses the use of barium silicate glass as a "microfiller" to achieve X-ray opacity in synthetic resin compounds. European patent EP 0 717 976 B1 teaches the use of a barium aluminum borosilicate glass microfiller with a particle size in the range of 0.7 µm.

[0012] Induced by the fact that the barium ions released from the glasses proved to be toxic, barium-free glasses were subsequently developed, in which, among other things, strontium compounds are used as contrast agents.

[0013] In addition, German patent DE 43 23 143 C1 discloses the use of strontium silicates as microfillers. Furthermore, European patent EP 0 511 868 A2 teaches the use of strontium phosphate / strontium apatite systems with a particle size of 10 µm.

[0014] In addition, oxide mixtures and mixed oxides of elements such as lanthanum, tungsten and zirconium have been proposed in the prior art for specifically barium-free radiopaque dental glasses - as in the international patent application WO 2007 / 048670 A2.

[0015] Furthermore, strontium / zinc / zirconium silicates were used as fillers or fillers - e.g. according to the teaching of the German patent DE 19 849 388 C2.

[0016] In addition, the prior art also discloses the use of pure mixed oxides in highly viscous systems – as, for example, according to the teachings of German patent application DE 34 21 155 A1, which discloses the use of oxides of a strontium / lanthanum / tungsten combination microfiller. However, with such use, the hardened composites often become opaque and generally lose fracture toughness as well as advantageous properties of other mechanical characteristics. Reducing the size of the filler particles into the upper nanometer range only provides an improvement with regard to optical properties and polishing.

[0017] As an alternative to the glasses, according to European patent application EP 0 238 025 A2, sparingly soluble complex fluoride compounds are also proposed - such as BaZrF 6 and SrZrF 6 as well as YF 3 - in addition to sparingly soluble rare earth fluorides, as disclosed, for example, in European patent application EP 0 189 540 A2.

[0018] Furthermore, international patent application WO 2002 / 055028 A2 discloses the use of lanthanide oxides as radiopaque microfillers, while German patent application DE 24 58 380 A1 uses La, Hf, Sr, and Ta oxides and their carbonates in glasses to achieve satisfactory radiolucency. According to the teaching of German patent application DE 29 35 810 A1, thorium and / or tantalum oxide are proposed in dental filling materials. However, this approach has not been established in practical application due to the radioactivity of thorium in addition to its heavy metal toxicity.

[0019] Furthermore, European patent application EP 0 143 362 A2 and German patent application DE 44 19 386 A1 disclose the use of reactive (acrylic) monomers containing covalently bonded bromine or iodine, which can generate some X-ray visibility.

[0020] According to the latest state of the art, nanoparticles are increasingly being used in the composite systems in question, as their decreasing particle size has less and less of a negative impact on optical properties. For example, European patent application EP 1 711 433 discloses the synthesis and use of nanoparticulate mixed flame oxides based on silicon dioxide (SiO₂) and rare earth oxides in dental composites, while according to German patent application DE 10 2006 045 628 A1, these mixed flame oxides have already been used in a radiopaque dental adhesive.

[0021] German patent application DE 10 2015 220 373 A1 also discloses the use of particles made of barium sulfate and ytterbium fluoride with a particle size of 25 - 120 nm in the form of an X-ray opaque filler in curable dental materials and further teaches the use of such a material for the field of additive manufacturing, preferably using 3D printing.

[0022] EP 1 366 774 A discloses a bone cement mixture formed from a polymer component containing a radiopaque contrast agent and a monomer component, wherein the radiopaque contrast agent is formed as a polymer with chemically bonded compounds of radiopaque elements (e.g. zirconyl dimethacrylate).

[0023] However, the filler-containing systems discussed above, described in the prior art, carry the risk that when transferred to low-viscosity resins – such as those used in additive manufacturing using the STL or DLP process – they may settle over time due to gravity and / or a concentration gradient may develop, which subsequently leads to the final product not having reproducible properties, particularly with regard to X-ray opacity.

[0024] Similar to classical X-ray diagnostics, radiopacity plays a crucial role in modern orthopedics and dentistry for differentiating between artificial dental and bone materials and natural tooth and bone material. Therefore, there is a constant need to be able to advantageously adjust the radiopacity of curable dental and bone materials, which are further processed into the corresponding cured, artificial dental and bone materials by polymerizing suitable polymerizable monomers.

[0025] The problem underlying the present invention is solved according to the invention by the composition claimed in claim 1, which provides a hardenable and radiopaque material. Furthermore, the present invention relates to a hardened material that can be produced from the hardenable material by polymerization, to methods for producing the hardenable and the hardened material, and to the use of the hardenable and the hardened material, i.e., the material.

[0026] The hardenable material can be used, among other things, in orthopedics as so-called bone cement, but especially also in dentistry as dental filling material, dental cement, dental base material, flowable composite material (flow material), crown and bridge material, for the production of inlays, onlays and as a core build-up material, as well as in radiographic diagnostics as a drilling template.

[0027] In addition, it was found that the materials according to the invention also stand out due to properties that make them highly interesting for use in the field of optical devices.

[0028] In a particular application, the curable material can be used as a building material in an additive manufacturing process using a digital data model, preferably in 3D printing, and in particular for the production of a product for use in the field of optics, preferably for the production of lenses and / or filters.

[0029] The hardenable material according to the invention for the production of a material can be produced by mixing the following starting materials: one or more polymerizable monomer(s), one or more strontium, zirconium, lead, barium, bismuth or rare earth compound(s) soluble in the monomer(s) or in the monomer mixture, one or more curing initiators, one or more auxiliary substances, characterized in that the auxiliary substance is an aromatic carboxylic acid or an aralkyl carboxylic acid, wherein the aralkyl carboxylic acid is a substituted or unsubstituted, saturated or unsaturated carboxylic acid, wherein the carboxylic acid is preferably phenylacetic acid or 3-phenylpropionic acid or trans-cinnamic acid.

[0030] Preferably, at least one of the polymerizable monomers is selected from the group of radically curable monomers, among which at least one of the polymerizable monomers is particularly preferably selected from the group of acrylic acid, acrylates, methacrylic acid or methacrylates or from their derivatives.

[0031] Examples of suitable radical-curable monomers of acrylic acid or...of methacrylic acid are: methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, 2-hydroxyethyl methacrylate, 3-hydroxypropyl methacrylate, 2-hydroxy-1,3-dimethacryloxypropane, n-butyl methacrylate, isobutyl methacrylate, hydroxypropyl methacrylate, glycidyl methacrylate, 2-methoxyethyl methacrylate, 2-Ethylhexyl methacrylate, benzyl methacrylate, 2,2-bis-(methacryloxyphenyl)propane, 2,2-bis-[4-(2-hydroxy-3-methacryloxypropoxy)phenyl]propane, 2,2-bis-(4-methacryloxydiethoxy-phenyl)propane, 2,2-bis-(4-methacryloxypolyethoxyphenyl)propane, Ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, butylene glycol dimethacrylate, Neopentyl glycol dimethacrylate, 1,3-butanediol dimethacrylate, 1,4-butanediol dimethacrylate, 1,6-hexanediol dimethacrylate, trimethylolpropane trimethacrylate, trimethylolethane trimethacrylate, pentaerythritol trimethacrylate, trimethylolmethane trimethacrylate, pentaerythritol tetramethacrylate and methacrylates having a urethane bond in their derivatized compound.

[0032] The following curable materials or dental materials are particularly preferred, selected from the group comprising methacrylic acid, butyldiglycol methacrylate, urethane dimethacrylate, iso-Bomyl methacrylate, tetrahydrofurfuryl methacrylate, 1,4-butanediol dimethacrylate, 2-[[(Butylamino)carbonyl]oxy]ethyl acrylate, bisphenol A dimethacrylate and / or methyl methacrylate.

[0033] The aforementioned monomers are used as the main component of, for example, dental materials for polymerization, mixed with at least one curing initiator for radical polymerization and, if necessary, with additional monomers, and with one or more strontium, zirconium, lead, barium, bismuth, or rare earth compounds described below, and possibly with additives. The mixtures thus obtained can be cured by radical polymerization.

[0034] Both the hardenable compositions and the hardened products - materials - are the subject of the present invention.

[0035] The rare earth metals of the periodic table include the chemical elements of group 3 (with the exception of actinium) and the lanthanides – a total of 17 elements. According to the definitions of inorganic nomenclature, this group of chemically similar elements is also called rare earth metals. The compounds derived therefrom are, among other things, the subject of the present invention according to claim 1. The rare earth compounds used according to the invention are derived, on the one hand, from the lighter rare earth metals – such as scandium (Sc, 21), lanthanum (La, 57), cerium (Ce, 58), praseodymium (Pr, 59), neodymium (Nd, 60), promethium (Pm, 61), samarium (Sm, 62) and europium (Eu, 63) – and, on the other hand, from the so-called heavier rare earth metals – such as yttrium (Y, 39), gadolinium (Gd, 64), terbium (Tb, 65), dysprosium (Dy, 66), holmium (Ho, 67), erbium (Er, 68), thulium (Tm, 69), ytterbium (Yb, 70), lutetium (Lu, 71).

[0036] In addition, the present invention comprises compounds of the elements strontium (Sr, 38), zirconium (Zr, 40), lead (Pb, 82), barium (Ba, 56) and bismuth (Bi, 83) soluble in the monomer or in the monomer mixture.

[0037] Suitable initiators for radical polymerization include those well-known from the prior art for hot, cold, and photocuring. Suitable initiators are listed, for example, in the Encyclopedia of Polymer Science and Engineering, Vol. 13, Wiley-Interscience Publishers, New York 1988.

[0038] Common thermal initiators include azo compounds such as azobis(isobutyronitrile) (AIBN) or azobis(4-cyanovaleric acid) or peroxides such as dibenzoyl peroxide, dilauryl peroxide, tert-butyl peroctoate, tert-butyl perbenzoate or di(tert-butyl) peroxide.

[0039] In accordance with the present invention, preferred UV curing initiators are embodied by compounds from the group of phosphine oxides, preferably diphenyl-(2,4,6-trimethylbenzoyl)phosphine oxide (TPO) and / or 2,4,6-trimethylbenzoylphenylphosphinate (TPO-L) and / or bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide (BAPO) and / or camphorquinone and / or a compound from the group of thioxanthones.

[0040] For the purposes of the present invention, the term auxiliary substances is understood to mean organic acids, wherein the organic acid is embodied by an aromatic carboxylic acid or by an aralkyl carboxylic acid.

[0041] The aralkylcarboxylic acid can be represented by a branched or unbranched carboxylic acid, or by a substituted or unsubstituted, saturated or unsaturated carboxylic acid.

[0042] Aralkylcarboxylic acids selected from the group comprising phenylacetic acid, 3-phenylpropionic acid and trans-cinnamic acid are particularly preferred.

[0043] Conveniently, the strontium, zirconium, lead, barium, bismuth and / or rare earth compound(s) are provided in the form of compounds from which in-situ The corresponding compounds soluble in the monomers are formed in concentrations in the subsequent polymer that allow X-ray visibility.

[0044] In a preferred embodiment, the lead, barium, bismuth, and / or rare earth compound(s) are already provided in the form of their compounds or complexes, which are soluble in the monomers or monomer mixture(s). The presence of metal ions in solution eliminates the problem of sedimentation at the low viscosity required for additive manufacturing, as occurs, for example, when using fillers. Consequently, the solutions or printing materials can be stored without problems, thus preventing the risk of printer nozzle clogging by agglomerated particles in inkjet-based systems.

[0045] Furthermore, the materials do not contain any particles that could disrupt photopolymerization by absorbing and scattering the incident light.

[0046] The resulting polymerized or hardened materials are crystal clear and contain no particles that could be considered defects and thus impair their mechanical properties. Fig. 1 proven for various elements (nickel and copper are not part of the present invention).

[0047] Furthermore, the macromolecular materials obtained after polymerization can be polished to an excellent standard, as they do not contain any disruptive filler particles.

[0048] The X-ray contrast agents dissolved in the polymer are always homogeneously distributed in the resin mixture and the polymerized materials, thus ensuring excellent reproducibility, which is further enhanced by Fig. 2 is documented.

[0049] In Fig. 2The first series shows X-ray images (taken with a voltage of 55 kV applied to the X-ray tube) of exemplary samples (labeled accordingly). The first series of images of the samples begins with standard aluminum (Al), followed by a sample with no metal content (0). These are followed by images of samples with a content of 5 and 10 wt% praseodymium (labeled 5 Pr and 10 Pr accordingly).

[0050] The second series shows X-ray images of test specimens containing 5 and 10 wt% erbium (5 Er 5 and 10 Er), followed by images of samples containing 5 wt% ytterbium (5 Yb) and barium (5 Ba).

[0051] The last row shows, among other things, the X-ray image of a sample containing 5 wt% lead (5 Pb).

[0052] This makes it possible to create complex radiographically visible structures that can be produced using traditional manual techniques, e.g., with autopolymerizing resins.

[0053] The additively manufactured structures fit as intended because the polymerization shrinkage that occurs is taken into account or factored in beforehand by the CAD / CAM software.

[0054] The use of polymerizable strontium, zirconium, barium, lead, bismuth or rare earth compounds significantly reduces migration.

[0055] Ultimately, the systems or curable materials according to the invention have an adjustable, low viscosity in the range of 500 - 3,000 mPas, whereas the composites known from the prior art are located well above 40,000 mPas. Examples:

[0056] 1. Production of an X-ray visible, praseodymium-containing polymer for the production of boron stencils on a DLP printer at 385 nm. (not according to the invention) 1.21 g praseodymium carbonate 5.03 g methacrylic acid 2.03 g butyl diglycol methacrylate 6.96 g urethane dimethacrylate 0.31 g TPO-L The mixture yields a clear, green solution which, after polymerization, produces a crystal-clear, green platelet. The X-ray visibility is approximately 70% A1 at slightly less than 5% Pr. 2. Production of radiopaque, europium-containing polymer 1,22 g Europium carbonate 4,06 g 3-Phenylpropionic acid 2,18 g Methacrylic acid 2,60 g ISO -Bornylmethacrylat 5,32 g Urethane dimethacrylate 0,37 g TPO-L The mixture yields a clear, slightly yellow solution which, after polymerization, produces a crystal-clear, yellowish platelet. The X-ray visibility is approximately 73% A1 at slightly less than 5% Eu. 3. Production of radiopaque, erbium-containing polymer 2,34 g Erbium carbonate 2,51 g 3-Phenylpropionic acid 2,91 g Phenyleacetic acid 3,01 g Methacrylic acid 2,00 g ISO -Bornylmethacrylat 3,17 g Butyl glycol methacrylate 0,27 g TPO The mixture yields a clear, pink solution which, after polymerization, produces a crystal-clear, pink platelet. The X-ray visibility is approximately 85% A1 at 10% Er. 4. Production of radiopaque lead-containing polymer for use as a printing material, e.g. for the production of x-ray-absorbing windows. 3,28 g lead oxide 3,02 g 3-Phenylpropionic acid 3,24 g Methacrylic acid 0,66 g ISO -Bornylmethacrylat 4,93 g Urethane dimethacrylate 0,33 g TPO-L The mixture yields a clear, slightly brownish solution which, after polymerization, produces a crystal-clear, slightly brown-tinted platelet. The X-ray visibility is 162% A1 with a lead content of slightly less than 20%. 5. Production of radiopaque, barium-containing polymer I 1,26 g Anhydrous barium hydroxide 2,99 g Methacrylic acid 0,99 g trans-cinnamic acid 4,03 g Butyl diglycol methacrylate 2,08 g Methacrylic acid anhydride 7,78 g Urethane dimethacrylate 0,36 g TPO The mixture yields a clear, slightly yellowish solution which, after polymerization, produces a crystal-clear, slightly yellowish-colored platelet. The X-ray visibility is approximately 70% A1 with slightly less than 5% Ba. 6. Production of radiopaque, barium-containing polymer II 2,49 g Anhydrous barium hydroxide 6,03 g Methacrylic acid 0,54 g Phenyleacetic acid 6,67 g Urethane dimethacrylate 0,36 g TPO The mixture yields a clear, slightly yellowish solution which, after polymerization, produces a crystal-clear, slightly yellowish disc through which reading is easily possible. The X-ray visibility is approximately 100% A1 at slightly less than 10% Ba. 7. Production of holmium-containing polymer suitable for applications in optics and surface coating 1,19 g Holmium carbonate 4,04 g 3-Phenylpropionic acid 2,17 g Methacrylic acid 0,66 g ISO -Bornylmethacrylat 5,88 g Urethane dimethacrylate 0,36 g TPO-L The mixture yields a clear, yellowish solution which, after the polymerization reaction, produces a clear, yellowish-colored platelet. The X-ray visibility is approximately 67% A1 at slightly less than 5% Ho. Upon exposure to artificial light, the monomer mixture and platelet are distinctly pink, while in daylight they appear only pale yellow ( Fig. 1 , test specimen G) appear. 8. Production of a zirconium-containing polymer (not according to the invention) 2,27 g Zirconium(IV) methacrylate 3,29 g Tetrahydrofurfuryl methacrylate 1,06 g Methacrylic acid 2,05 g Triethylene glycol dimethacrylate 7,41 g Phenylglycerol dimethacrylate 0,36 g TPO-L The mixture yields a clear, yellowish solution which, after the polymerization reaction, produces a clear, yellowish-colored platelet. 9. Production of a strontium-containing polymer (not according to the invention) 0,28 g Strontium hydroxide 4,39 g Tetrahydrofurfuryl methacrylate 2,04 g Methacrylic acid 2,71 g Mono-2-methacryloyloxyethyl succinate 5,95 g Bisphenol A glycidyl methacrylate 0,32 g TPO-L

[0057] The mixture yields a clear, almost colorless solution which, after the polymerization reaction, produces a clear platelet.

[0058] Thus, the present invention relates to a hardenable, radiopaque material for the production of a material, producible by mixing starting materials, wherein the following are used as starting materials to be mixed: one or more polymerizable monomer(s), one or more strontium, zirconium, lead, barium, bismuth or rare earth compound(s) soluble in the monomer(s) or in the monomer mixture, one or more curing initiator(s) and one or more auxiliary substances, characterized in that the auxiliary substance is an aromatic carboxylic acid or an aralkyl carboxylic acid, wherein the aralkyl carboxylic acid is a substituted or unsubstituted, saturated or unsaturated carboxylic acid, wherein the carboxylic acid is preferably phenylacetic acid or 3-phenylpropionic acid or trans-cinnamic acid.

[0059] Preferably, the present invention relates to a curable material in which at least one of the polymerizable monomers is selected from the group of radically curable monomers.

[0060] Furthermore preferably, the present invention relates to a curable material in which at least one of the polymerizable monomers is selected from the group consisting of acrylic acid, acrylates, methacrylic acid or methacrylates or from their derivatives.

[0061] Furthermore preferably, the present invention relates to a curable material, wherein the acrylic acid derivative and / or the methacrylic acid derivative is selected from the group comprising acrylic acid esters, methacrylic acid esters, acrylamide or methacrylamide.

[0062] Furthermore preferably, the present invention relates to a curable material, wherein the acrylic acid and / or methacrylic acid derivative is selected from the group comprising methacrylic acid, butyl diglycol methacrylate, urethane dimethacrylate, iso-boron methacrylate, tetrahydrofurfuryl methacrylate, 1,4-butanediol dimethacrylate, 2-[[(Butylamino)carbonyl]oxy]-ethyl acrylate, bisphenol A dimethacrylate and / or methyl methacrylate.

[0063] The present invention more preferably relates to a hardenable material, wherein the lead, barium, bismuth or rare earth compound is a polymerizable strontium, zirconium, lead, barium, bismuth or rare earth compound and / or an inorganic or organic rare earth salt or a complex compound.

[0064] The present invention more preferably relates to a hardenable material in which the lead, barium, bismuth and / or rare earth compound is contained in a concentration that enables X-ray visibility.

[0065] Furthermore preferably, the present invention relates to a curable material, wherein the curing initiator is a UV curing initiator.

[0066] Furthermore preferably, the present invention relates to a curable material, wherein the curing initiator consists of a redox-2 component system and contains as an auxiliary a powdered component which, after mixing with the liquid component, yields a self-curing material.

[0067] Furthermore, the present invention preferably relates to a curable material, wherein the UV initiator is from the group of phosphine oxides, preferably diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (TPO) and / or 2,4,6-trimethylbenzoylphenyl phosphinate (TPO-L) and / or bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide (BAPO) and / or camphorquinone and / or a compound from the group of thioxanthones.

[0068] The auxiliary substance in the curable material of the present invention is an aromatic or an aralkylcarboxylic acid.

[0069] Furthermore preferably, the present invention relates to a curable material wherein the carboxylic acid derivative is phenylacetic acid and / or 3-phenylpropionic acid and / or trans-cinnamic acid.

[0070] Furthermore preferably, the present invention relates to a curable material in which the polymerizable partial structure is represented by at least one radically polymerizable group.

[0071] The present invention more preferably relates to a curable material, wherein the complexing agent is selected from the group comprising 2-methacryloyloxyethylacetoacetate (AAEMA), bis(2-methacryloyloxyethyl) pyromellitate, methacryloyloxyethyl phthalate, methacryloyloxyethyl maleate, methacryloyloxyethyl succinate and / or their derivatives.

[0072] The present invention more preferably relates to a curable material, wherein the complexing agent, or more preferably the curable mixture as a whole, has a vapor pressure of less than 1 mbar at 20 °C at room temperature, particularly preferably less than 0.3 mbar at 20 °C and most preferably less than 0.1 mbar at 20 °C.

[0073] Furthermore preferably, the present invention relates to a curable material, wherein the curable material, after polymerization, yields a material that is transparent to electromagnetic waves in the visible light range and may be colored due to the metal ions contained.

[0074] The present invention more preferably relates to a curable material for use in a method for the surgical or therapeutic treatment of the human or animal body and / or for use in a diagnostic method performed on the human or animal body, preferably for specific applications in a therapeutic procedure for the temporary or permanent filling of a dental cavity, as well as in a therapeutic procedure as a dental filling material, dental cement, dental base material, as a flowable composite material (flow material), as a crown material, as an inlay and / or onlay, as a drilling template and / or as a core build-up material and / or in a diagnostic procedure as a drilling template or radiopaque contrast agent.

[0075] Furthermore, the present invention relates to a method for producing a hardenable material comprising the following steps: (i) Producing or providing the starting materials as defined in any one of claims 1 to 21, or producing or providing intermediate products from the starting materials as defined above; (ii) Mixing the starting materials produced or provided according to step (i) or the intermediate products produced or provided according to (i) such that the curable material is obtained in each case.

[0076] Furthermore, the present invention preferably relates to the use of a curable material - as defined above - in 3D printing.

[0077] Furthermore, the present invention particularly preferably relates to the use of a hardenable material - as defined above - as a building material in an additive manufacturing process using a digital data model.

[0078] Furthermore, the present invention particularly preferably relates to the use of the hardenable material - as defined above - for the manufacture of a dental product, preferably for the manufacture of a dental product selected from the group consisting of artificial teeth, inlays, onlays, crowns, bridges, milling blanks, implants and dental components as well as drilling templates.

[0079] Furthermore, the present invention relates to the use of a hardenable material for the manufacture of a product for use in the field of optics, preferably for the manufacture of lenses and / or filters.

[0080] Furthermore, the present invention relates to a method for manufacturing a dental product using a generative manufacturing process employing a digital data model, comprising the following steps: (i) Manufacturing or providing a curable dental material as defined above, preferably manufacturing it according to the method mentioned above, and (ii) processing the manufactured or provided curable dental material in the additive manufacturing process using a digital data model, resulting in the dental product or a precursor to the dental product. wherein the dental product is preferably selected from the group consisting of artificial teeth, inlays, onlays, crowns, bridges, milling blanks, implants, drilling templates and dental components.

[0081] Furthermore, the present invention relates to a hardened material or a material obtainable by polymerization of polymerizable monomers in a hardenable material as defined above.

[0082] Furthermore, the present invention relates to a kit comprising one or more than one syringe and (i) one, two or more than two curable materials as defined above and / or (ii) one, two or more than two base pastes and one, two or more catalyst pastes, wherein a curable material - as defined above - is obtainable by mixing a base paste and the associated catalyst paste.

Claims

1. Curable X-ray visible material for producing a material, which can be produced by mixing starting materials, wherein the following starting materials are used for mixing: - one or more polymerisable monomer(s), - one or more strontium, zirconium, lead, barium, bismuth or rare earth compounds which are soluble in the monomer or in the monomer mixture, - one or more curing initiators, and - one or more auxiliary substances, characterised in that the auxiliary material is an aromatic carboxylic acid or an aralkyl carboxylic acid, wherein the aralkyl carboxylic acid is a substituted or unsubstituted, saturated or unsaturated carboxylic acid, wherein the carboxylic acid is preferably phenylacetic acid or 3-phenylpropionic acid or trans-cinnamic acid.

2. Curable material according to claim 1, characterised in that at least one of the polymerisable monomers is selected from the group consisting of acrylic acid, acrylates, methacrylic acid or methacrylates or theirderivatives, wherein preferably the acrylic acid derivative or the methacrylic acid derivative is selected from the group comprising acrylic acid esters, methacrylic acid esters, acrylamide or methacrylamide, whereby the acrylic acid or methacrylic acid derivative is preferably selected from the group comprising methacrylic acid, butyldiglycol methacrylate, urethane dimethacrylate, iso-bornyl methacrylate, tetrahydrofurfuryl methacrylate, 1,4-butanediol dimethacrylate, 2-[[(butylamino)carbonyl] oxy] ethyl acrylate, bisphenol-A-dimethacrylate and methyl methacrylate.

3. Curable material according to claim 1 or 2, characterised in that the strontium, zirconium, lead, barium, bismuth or rare earth compound is a polymerisable strontium, zirconium, lead, barium, bismuth or rare earth compound or an inorganic or organic rare earth salt or a complex compound, whereby the strontium, zirconium, lead, barium, bismuthor rare earth compound is preferably contained in a concentration that enables X-ray visibility, and preferably the curing initiator is a UV curing initiator, or preferably the curing initiator consists of a redox-2-component system and contains a powdered component as an auxiliary material, which, after mixing with the liquid component, produces a self-curing material.

4. Curable material according to any one of claims 1 to 3, characterised in that the UV initiator is selected from the group comprising phosphine oxides, thioxanthones and camphorquinone, preferably the UV initiator is selected from the group comprising diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (TPO), 2,4,6-trimethylbenzoyl / phenylphosphinate (TPO-L) and bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide (BAPO).

5. Curable material according to any one of claims 1 to 4, characterised in that the monomer mixture has a vapour pressure at room temperature of less than 1 mbar / 20 °C, and preferably the curable mixture has a vapour pressure at room temperature of less than 0.3 mbar / 20 °C, and preferably the curable mixture has a vapour pressure at room temperature of less than 0.1 mbar / 20 °C.

6. Curable material according to claims 1 to 5, characterised in that after polymerisation, the curable material yields a material that is transparent to electromagnetic waves in the visible light range, colourless or coloured.

7. Curable material according to one of claims 1 to 6 for use in a method for the surgical or therapeutic treatment of the human or animal body and / or for use in a diagnostic method performed on the human or animal body, preferably for specific use. - in a therapeutic procedure for temporarily or permanently filling a dental cavity, as well as in a therapeutic procedure as - dental filling material, - dental cement, - dental underfill material, - as a flowable composite material (flow material), - as a crown material, - as an inlay or onlay, - as a drilling template - or as a core build-up material and / or in a diagnostic procedure as - drilling template - X-ray contrast medium.

8. Method for producing a curable dental material according to one of claims 1 to 6, comprising the following steps: (i) producing or providing the starting materials as defined in one of claims 1 to 6, or producing or providing preliminary products from the starting materials as defined in one of claims 1 to 7 (ii) mixing the starting materials produced or provided in accordance with step (i) or the preliminary products produced or provided in accordance with (i) so that the curable dental material results in each case.

9. Use of a curable material according to one of claims 1 to 6 as a building material in a generative manufacturing process using a digital data model, and preferably in 3D printing or preferably for the manufacture of a dental product, preferably for the manufacture of a dental product selected from the group consisting of artificial teeth, inlays, onlays, crowns, bridges, milling blanks, implants and prefabricated dental parts, preferably for the manufacture of a product for use in the field of optics, and preferably for the manufacture of lenses and / or filters.

10. Method for manufacturing a dental product by means of a generative manufacturing process using a digital data model, comprising the steps: (i) producing or providing a curable material according to one of claims 1 to 6, (ii) processing the manufactured or provided curable material in the generative manufacturing process using a digital data model so that the dental product or a precursor of the dental product results, and preferably the dental product is selected from the group consisting of artificial teeth, inlays, onlays, crowns, bridges, milling blanks, implants, drilling templates and prefabricated dental parts.

11. Cured material obtainable by polymerisation of polymerisable monomers in a curable material according to any one of claims 1 to 6.

12. Kit comprising - one or more syringes and (i) one, two or more than two curable materials according to any one of claims 1 to 6 and / or (ii) one, two or more than two base pastes and one, two or more catalyst pastes, wherein a curable material according to any one of claims 1 to 6 can be obtained by mixing a base paste and the corresponding catalyst paste.