Method, apparatus and system for producing dental prostheses by jet printing

Abstract

The invention relates to a method, an apparatus and a system for producing dental prostheses by jet printing. The invention provides a method for producing a dental restoration 100 by jet printing, comprising the steps of: jet printing (S101) one or more layers of a dental restoration by means of a ceramic slurry; and jet printing (S102) a coloring solution onto the one or more layers.

Description

Technical Field

[0001] The present invention relates to a method for producing dental restorations by inkjet printing and a production device for producing dental restorations by inkjet printing. Background Art

[0002] Differently colored solvent-based ceramic slurries, such as slurries made of zirconia, can be selectively applied drop by drop in a large number of layers using a jetting process (inkjet process). However, processing highly filled ceramic slurries places high demands on the print head used in terms of particle size, filling level, as well as viscosity and wear. Inkjet printing (jetting) of aqueous ceramic slurries is an alternative to solvent-based slurries. Here, the jetted material layer is dried without cracks. Summary of the Invention

[0003] The technical task of the present invention is to improve the multicolor 3D printing process using ceramic slurry inkjet.

[0004] This task is solved by the subject matter according to the present invention.

[0005] According to a first aspect, this technical task is solved by a method for producing dental restorations by inkjet printing, the method comprising the steps of: inkjet printing one or more layers of the dental restoration with a ceramic slurry; and inkjet printing a coloring solution onto the one or more layers. This allows the selective application process of the slurry and the selective coloring process to be separated from each other. The same or different print heads can be used for the application process and the coloring process.

[0006] On the other hand, if pre-colored slurries are used, which also have different translucencies and / or different mechanical properties, each of these slurries is assigned its own print head. In contrast, the method can reduce the number of print heads used for applying the slurry, since the coloring is carried out separately by subsequent inkjet printing of the coloring solution from the slurry accumulation.

[0007] In a technically advantageous embodiment of the method, the one or more layers are dried before inkjet printing the coloring solution. This achieves technical advantages such as less diffusion of the coloring solution and improved local uniformity of the coloring.

[0008] In a further technically advantageous embodiment of the method, the applied coloring solution is fixed by means of an alkaline solution. The alkaline solution can be applied to the layer after or before applying the coloring solution. This achieves technical advantages such as reducing the flow of the coloring solution.

[0009] In a further technically advantageous embodiment of the method, the ceramic slurry has an alkaline pH. This achieves technical advantages such as the coloring solution being automatically fixed by the slurry.

[0010] In a technically advantageous embodiment of the method, the coloring solution is jet-printed onto one or more wet layers. This achieves technical advantages such as precipitation reactions occurring in the coloring solution and the method being able to proceed more quickly.

[0011] In a further technically advantageous embodiment of the method, the coloring solution is fixed by contact with the ceramic slurry. This achieves technical advantages such as the method being carried out more effectively.

[0012] In a further technically advantageous embodiment of the method, one or more wet layers are dried together with the applied coloring solution. This achieves technical advantages such as the next layer being able to be applied immediately.

[0013] In a further technically advantageous embodiment of the method, the steps of producing the dental restoration are repeated. This achieves technical advantages such as the entire dental restoration being able to be constructed and colored.

[0014] In a further technically advantageous embodiment of the method, the dental restoration is sintered in a sintering furnace. This achieves technical advantages such as a dental restoration with high strength being able to be produced.

[0015] In a further technically advantageous embodiment of the method, before the sintering process, a drying and / or debinding step is carried out on the produced dental restoration. The drying and / or debinding step can be carried out in a separate heat treatment or can be an upstream treatment step in the sintering process. Drying is usually carried out at a temperature of 25 °C to 200 °C, preferably 30 °C to 180 °C, and particularly preferably 40 °C to 150 °C. Additionally, the humidity can be adjusted between 10% and 90%, preferably 15% and 85%, and particularly preferably 20% and 80%. Debinding is usually carried out at the following temperatures: 50 °C to 600 °C, preferably between 100 °C and 600 °C, and particularly preferably 200 °C to 600 °C. The heating rate is between 0.1 and 10 K / min, preferably between 0.2 and 10 K / min, and particularly preferably between 0.5 and 10 K / min.

[0016] According to a second aspect, this technical task is solved by a production device for producing dental restorations by jet printing, the production device comprising a first print head for jet-printing one or more layers of a dental restoration by means of a ceramic slurry; and a second print head for jet-printing a coloring solution onto one or more layers. The production device achieves the same technical advantages as the method according to the first aspect.

[0017] In a technically advantageous embodiment of the production device, the first print head and the second print head are integrated in a common print module. This achieves technical advantages such as simplifying the design of the production device.

[0018] In a further technically advantageous embodiment of the production device, the first print head and the second print head are independently controllable. This enables technical advantages such as, for example, the slurry and the coloring solution can be applied independently of each other.

[0019] In a further technically advantageous embodiment of the production device, the production device includes a dithering module for calculating intermediate color values by mixing at least two coloring solutions. This enables technical advantages such as, for example, further improving the realistic appearance of dental restorations.

[0020] In a further technically advantageous embodiment of the production device, the dithering module is configured to use different two-dimensional dithering patterns in successive layers of the dental restoration. This enables technical advantages such as, for example, preventing the formation of streaks or moiré patterns in dental restorations.

[0021] According to a third aspect, this technical task is solved by an inkjet printing system comprising a production device for producing dental restorations by inkjet printing; at least one ceramic slurry for inkjet printing one or more layers of a dental restoration; and a coloring solution for inkjet printing onto one or more layers. The inkjet printing system enables the same technical advantages as the method according to the first aspect.

[0022] In a technically advantageous embodiment of the inkjet printing system, at least one ceramic slurry and / or the coloring solution is stored in a container. This enables technical advantages such as, for example, the ceramic slurry and / or the coloring solution can be stored reliably.

[0023] In a further technically advantageous embodiment of the inkjet printing system, the container is replaceable. This enables technical advantages such as, for example, the solution can be easily exchanged. Description of the Drawings

[0024] Exemplary embodiments of the present invention are shown in the drawings and described in more detail below, wherein:

[0025] Figure 1 A diagram showing different regions of an incisor is shown;

[0026] Figure 2 A schematic diagram of a dental restoration is shown;

[0027] Figure 3 A schematic diagram of a production device for producing dental restorations is shown;

[0028] Figure 4 A schematic diagram of a method for producing dental restorations by inkjet printing is shown;

[0029] Figure 5Schematic diagram showing an additional method for producing dental restorations by inkjet printing;

[0030] Figure 6 Table showing the composition of different coloring solutions; and

[0031] Figure 7 Block diagram showing a method for producing dental restorations by inkjet printing. Detailed Description

[0032] Figure 1 Illustration showing different regions of tooth 105. Tooth 105 includes an inner dentin core 101 and an outer tooth enamel 103. Optionally, an intermediate region 115 is present between the dentin core 101 and the tooth enamel 103, and this intermediate region can also be assigned a ceramic slurry 109 and a coloring solution 107 of its own choice.

[0033] The opaque dentin core 101 is responsible for the basic coloring of tooth 105. It emits light through the incisal tooth enamel 103. Tooth enamel 103 is naturally translucent. Translucency is the partial light transmittance of an object. In order to make the dental restoration look as realistic as possible, this structure of tooth 105 is also used for artificial dental restorations. For this purpose, materials with different optical properties are used in the production of dental restorations.

[0034] Figure 2 Schematic diagram showing dental restoration 100. Dental restoration 100 is used as a dental prosthesis and is formed, for example, by a dental bridge, a dental crown, a veneer, an inlay, an onlay, an abutment, a complete or partial prosthesis. Dental restoration 100 is constructed, for example, using different ceramic slurries 109. The ceramic slurry includes partially stabilized ZrO 2 and / or Al 2 O 3 particles. Al 2 O 3 may have been incorporated in the same way as the stabilizing ions. Partial stabilization is generally achieved by incorporating CaO, MgO, Y 2 in ZrO 2 O 3 La 2 O 3 CeO 2 or CeO 2 O 3 and mixtures thereof. Preferred embodiments contain Y

[0035] 2 O 3 as a stabilizer in an amount ranging from 1 to 10 mol%, particularly preferably in an amount ranging from 2 to 8 mol%, and even more particularly preferably in an amount ranging from 2.5 to 6 mol%. For this purpose, during the spatial production of dental restoration 100 by means of an inkjet printing process, these slurries 109 are selectively used in the respective regions.The dental prosthesis 100 is constructed from successive layers printed on top of each other. The ceramic powder of the slurry 109 may already be provided with a predetermined translucency. Mixing these slurries 109 results in the dental prosthesis 100 having a desired translucency in the corresponding spatial regions.

[0036] After selectively applying a layer of the slurry 109 using an inkjet printing process, the layer is dried by evaporating the solvent or water acting as a binder without cracking. What remains is a porous white body layer with a layer thickness of 1 µm to 50 µm and a density of at least 2.5 g / cm³. This process is repeated until the entire dental prosthesis 100 is spatially built up in layers.

[0037] In the case of ZrO 2 For the slurry 109, different yttrium-doped ceramic powders (3 mol% yttrium - 3Y-TZP, 4 mol% yttrium - 4Y-TZP, 5 mol% yttrium - 5Y-TZP) can also be used for different strengths.

[0038] 3Y-TZP = low translucency / high strength

[0039] 4Y-TZP = medium translucency / medium strength

[0040] 5Y-TZP = high translucency / low strength

[0041] However, if different pre-colored slurries 109 are used, and all of these pre-colored slurries also have different translucencies and / or mechanical properties, then each of these slurries 109 is assigned a separate print head 111-1. For example, if a common four-color scheme such as CMKY (cyan, magenta, yellow, key / white) is used to cover the entire color space, and slurries with different translucencies or strengths are also used in three variants, then 3 x 4 = 12 slurries 109 are included in 12 print heads. The production of these different slurries 109 is also complex. These large quantities of slurries 109 are kept and maintained as different items.

[0042] Figure 3 A schematic view of a production apparatus 200 for producing a dental prosthesis 100 by inkjet printing of an aqueous-based or solvent-based slurry 109 is shown. For additive manufacturing of ceramic, dental multi-materials, and multi-color prostheses 100 by means of inkjet printing, the base slurry 109 is processed.

[0043] The production apparatus 200 includes a plurality of receiving containers 119-1, in which a base slurry 109 and a support material 110 having different optical properties are arranged. Additionally, the production apparatus 200 includes at least several receiving containers 119-2, in which a coloring solution 107 and an alkaline solution 108 for fixing the coloring solution are accommodated. A production apparatus for producing a dental prosthesis by inkjet printing; at least one ceramic slurry; and a coloring solution for jet-printing a printing solution together form an inkjet printing system.

[0044] The ceramic slurries 109 are each applied drop by drop in a plurality of layers 117-1, …, 117-n by means of a designated print head 111-1 in order to spatially layer-build a dental prosthesis 100. The print head 111-1 is movable in two directions so that the slurry 109 can be printed at any position. The slurry 109 having a droplet volume typically of 10 to 100 pL is used for selective material application, and the use of this slurry eliminates a time-consuming debinding process. For example, an electro-controlled piezoelectric element is used to eject droplets. A bubble jet technique can also be used to eject slurry droplets. At least one additional print head 111-3 is used to apply the support material 110, by which the support material 110 can be selectively applied.

[0045] To apply the coloring solution 107, at least one additional print head 111-2 is used, by which the coloring solution 107 can be jet-printed onto one or more of the layers 117-1, …, 117-n. The print head 111-2 is also movable in two directions so that the coloring solution 107 can be printed at any position.

[0046] Optionally, at least one additional print head 111-4 is used to apply the alkaline solution 108 to fix the coloring solution 107, by which the alkaline solution 108 can be jet-printed onto one or more of the layers 117-1, …, 117-n. The print head 111-2 is also movable in two directions so that the alkaline solution 108 can be printed at any position. The print heads 111-1, 111-2, 111-3, and 111-4 can be independently controlled or integrated in a common print module.

[0047] The production apparatus 200 provides a reduced number of possible pre-colored and yttrium-doped neutral base slurries 109 to minimize the number of print heads 111-1 and 111-2 and still achieve aesthetic and functional results of the dental prosthesis 100. The final coloring is completed individually by selectively applying the coloring solution 107.

[0048] The desired tooth color is composed of and mixed from different coloring solutions 107. A subtractive color system is used, which spans a limited dental color space (dental color gamut). Then, these coloring solutions 107 are created by color mixing, three-dimensional halftoning, or dithering at various ratios within the limited dental color space (color gamut), which covers common tooth colors but not all colors.

[0049] When doing so, the different coloring solutions 107 are selectively applied to layers 117-1, …, 117-n using a 3D dithering algorithm performed by a dithering module. For this purpose, the dithering module includes a processor for performing the 3D dithering algorithm and a digital data memory for storing the calculated mixing ratios and the dithering algorithm. The processor includes any hardware system, component, or mechanism for processing data, signals, or other information. The processor can include a system having a central processing unit (CPU), multiple data processing units (MPU), a dedicated circuit for implementing functions, or other systems. The data memory can include a hard disk, a flash card, a random access memory (RAM), or a read-only memory (ROM).

[0050] During dithering, using an inkjet printing process, the different coloring solutions are selectively applied at certain ratios onto a printing plane and form a two-dimensional printing pattern. The 3D dithering algorithm also calculates different two-dimensional dithering patterns to be applied in multiple layers 117-1, …, 117-n on top of each other. This can prevent optical artifacts such as stripes or moiré patterns from appearing on vertical surfaces. These coloring solutions 107 are created by color mixing, three-dimensional halftoning, or dithering at various ratios within the limited dental color space (color gamut), which covers common tooth colors but not all colors.

[0051] When using a highly viscous slurry 109 with a viscosity greater than 100 mPas and highly filled, special requirements are posed on the printhead 111-1 and its fluid system. The printhead 111-1 is compatible with the binder and / or the carrier material of the slurry 109 used, such as being compatible with water in the case of an aqueous slurry, to avoid incompatibilities and consequences such as corrosion on the printhead.

[0052] After selectively applying the slurry 109 to layers 117-1, …, 117-n by means of an inkjet printing process, the layers 117-1, …, 117-n are dried without cracks by evaporating the solvent or water acting as the binder. The ceramic powder of the slurry 109 can have been colored to a certain color, such as a base color or a tooth color. What remains is a porous white body layer with a layer thickness of 1 μm to 50 μm and a density of at least 2.5 g / cm 3 and the process is repeated until the entire dental prosthesis 100 is spatially built up in layers.

[0053] If there are two slurries 109 with different opacities, the high-strength and opaque slurry 109 can be used for the dentin core, and the normal-strength and highly translucent slurry 109 can be used for the incisal edge. After the application of 1 - n layers 117 - 1, ……, 117 - n of the material, a coloring solution, such as a nitrate solution (acid), is selectively jet-printed according to the corresponding color coding or color information for selective coloring.

[0054] Figure 4 A schematic diagram of a method for producing a dental prosthesis 100 by jet printing is shown. In step S201, first, layer-by-layer selective material application of the slurry 109 is carried out by means of a jet printing process (inkjet process). In step S102, the applied slurry layer is dried, for example, by supplying hot air. In step S203, the first to nth applied layers 117 - 1, ……, 117 - n (green layers) of the slurry 109 are selectively colored with a coloring solution. Here, the coloring solution is also printed onto the first to nth applied layers 117 - 1, ……, 117 - n by means of jet printing. In step S204, the printed coloring solution is locally fixed with an alkaline solution 108 having a pH greater than 7. Subsequently, steps S201 to S204 are repeated until the dental prosthesis 100 is completely constructed in space.

[0055] For this method, aqueous-based slurries or solvent-based slurries 109 can be processed. Here, the selective material application (step S201) and the selective coloring (step S203) are carried out separately.

[0056] Figure 5 A schematic diagram of another method for producing a dental prosthesis 100 by jet printing is shown. In step S301, first, layer-by-layer selective material application of an alkaline slurry 109 is carried out by means of a jet printing process (inkjet process).

[0057] The alkaline slurry 109 has a pH greater than 7. Conventional alkaline slurries 109 contain H 2 O, a dispersion aid, such as 0 to 5% by weight, preferably 0.01 to 5% by weight of a carboxylic acid derivative (citric acid) or 0 to 5% by weight of ammonium polyacrylate (NH 4 PAA), preferably 0.01 to 5% by weight. The pH (8 - 11) can be adjusted with NH 4 OH. The alkaline adjustment of the slurry 109 has the following advantage: The ceramic slurry 109 is less aggressive with respect to corrosion of the metal components of the print head.

[0058] In addition, the slurry may contain small amounts, such as 0 to 5% by weight, preferably 0.001 to 5% by weight of a thickening agent to adjust the viscosity and / or sedimentation behavior, such as polyvinylpyrrolidone, cellusol derivatives or xanthan gum. The sedimentation behavior ensures that the suspension remains stable over a longer period of time and counteracts sedimentation.

[0059] In step S302, the still wet and undried applied layers 117-1, …, 117-n (green layers) of the slurry 109 are selectively colored by means of the coloring solution. This causes a precipitation reaction to occur as soon as the coloring solution (nitric acid) comes into contact with the wet slurry 109. The dissolved ions of the 3d and 4f elements precipitate in the form of hydroxides due to the change in pH when contacting the wet layer. This results in the formation of, for example, Fe(OH) 3 or Er(OH) 3 .

[0060] In step S303, the coloring solution is automatically fixed by contacting the alkaline slurry 109. In step S304, the wet-on-wet colored layers 117-1, …, 117-n are dried, for example by supplying hot air, without cracks. Then steps S301 to S304 are repeated until the dental prosthesis 100 is spatially constructed.

[0061] For this method, an aqueous-based slurry or a solvent-based slurry 109 can be processed. The selective material application (step S301) and the selective coloring (step S302) are carried out separately.

[0062] Figure 6 A table showing compositions with different coloring solutions 107 is presented. The coloring solution 107 has a low viscosity and can be jet-printed using an inkjet print head with DOD technology or bubble jet technology. The print head can be integrated with multiple color channels for multi-color printing. The print head can apply the coloring solution to the layers 117-1, …, 117-n at a high resolution of ≥720 dpi.

[0063] In the case of six available print heads, only one print head is used for the medium translucency slurry 109 and one print head for the support material 110. For seven available print heads, two print heads are used for the opaque slurry 109 and the highly translucent slurry 109 respectively, and one print head for the support material 110. The other four print heads are used for the coloring solution 107.

[0064] The coloring solution 107 is an aqueous-based nitrate or chloride salt solution. The coloring solution 107 includes various metal salts (e.g., Fe(NO 3 ) 3 *9H 2 O; Pr(NO3 ) 3 *6H 2 O; Tb(NO 3 ) 3 *5H 2 O; Er(NO 3 ) 3 *5H 2 O; Mn(NO 3 ) 2 *4H 2 O; Co(NO 3 ) 2 *6H 2 O; Cr(NO 3 ) 3 *9H 2 O; Mg(NO 3 ) 2 *6H 2 O; Al(NO 3 ) 3 *9H 2 O; Cu(NO 3 ) 2 *3H 2 O; Zn(NO 3 ) 2 *6H 2 O; Y(NO 3 ) 3 *6H 2 O; La(NO 3 ) 3 *6H 2 O; Ce(NO 3 ) 3 *6H 2 O; Nd(NO 3 ) 3 *6H 2 O; Sm(NO 3 ) 3 *6H 2 O; Gd(NO 3 ) 3 *6H 2 O; Yb(NO 3 ) 3 *6H 2 O; Ni(NO 3 ) 2 *6H 2 O; Co(NO 3 ) 2 *6H 2 O; Ga(NO 3 ) 3 *x H 2 O; In(NO3 ) 3 xH 2 O is dissolved to different concentrations. The concentration depends on the desired color intensity but should not exceed the solubility limit of the salt. However, depending on the desired composition, the coloring solution 107 can also be significantly more concentrated. However, increasing the ion concentration increases the viscosity or shifts the pH into the acidic range (<7). The higher viscosity of the coloring solution is advantageous to reduce the depth of penetration or the diffusion depth of the coloring solution into the dry layer.

[0065] Water and nitric acid (HNO 3 ) can be used as the base acid. This means that only four nitrate solutions (Fe(NO 3 ) 3 .9H 2 O, Er(NO 3 ) 3 .5H 2 O, Cr(NO 3 ) 3 .9H 2 O, Mn(NO 3 ) 2 *4H 2 O, Tb(NO 3 ) 3 *5H 2 O and Pr(NO 3 )3.6H 2 O) are used as the coloring solution 107 to produce tooth colors. At least only three nitrate solutions (Fe yellow, Er pink, Cr gray) are required. Other salts are used for finer color adjustment.

[0066] Additionally, variable components of yttrium or ytterbium in the coloring liquid can be used to adjust the opacity of the slurry 109 of the dental restoration 100. For example, the elements yttrium, ytterbium, neodymium, and europium are used as translucency enhancers, and aluminum and silicon are used as opaque liquids. A suitable coloring solution can be used to increase the yttrium content. In this way, different opacity values can be achieved in the dental restoration 100, such as being opaque for the dentin core and translucent for the incisal edge.

[0067] Figure 7 A block diagram of a method for producing a dental restoration 100 by inkjet printing is shown. In step S101, one or more layers 117-1,..., 117-n of the dental restoration 100 are inkjet printed with the ceramic slurry 109. In step S102, the coloring solution 107 is then inkjet printed onto the layers 117-1,..., 117-n.

[0068] If the penetration depth of the coloring solution 107 is greater than the thickness of the single layers 117-1, …, 117-n, the coloring can only be carried out after applying the multi-layer slurry 109. The penetration or diffusion depth of the coloring solution 107 can also be controlled by adjusting the viscosity. This is done by adding a suitable thickener that is stable within the pH range of the coloring solution. A suitable thickener is, for example, polyvinylpyrrolidone (PVP). The penetration or diffusion depth of all coloring solutions used can reach a uniform level to achieve as stable a process as possible.

[0069] It makes sense to use different printhead technologies because the slurry 109 and the coloring solution 107 have different rheological properties. The slurry 109 is highly viscous (10 - 1000 mPas, depending on the shear rate) and contains an abrasive filler in the form of ceramic particles in a high weight / volume ratio. A low viscosity of the slurry 109 between 10 - 500 mPas is advantageous, and a viscosity between 10 - 100 mPas is even more advantageous. The higher the viscosity of the slurry 109, the more difficult it is to process using an inkjet printhead based on MEMS technology.

[0070] On the other hand, the coloring solution 107 has a low viscosity (0.5 - 50 mPas). Additionally, the volume to be processed is different in each case, with the volume ratio of the slurry 109 being approximately 98% and the volume ratio of the coloring solution 107 being approximately 2%. The main volume to be processed is the slurry 109, while the volume of the coloring solution 107 to be processed is smaller. The coloring solution 107 and the slurry 109 can be stored in accommodation containers 119-1 and 119-2 of different sizes.

[0071] The coloring solution 107 can be inkjet printed after the applied layers 117-1, …, 117-n have dried or on the wet layers 117-1, …, 117-n (wet-on-wet). When the coloring solution 107 is inkjet printed onto the dried layers 117-1, …, 117-n, the penetration depth of the coloring solution 107 should be controllable.

[0072] The fully formed dental restoration 100 is then sintered in a sintering furnace. The slurry 109 together with the coloring solution 107 can be adjusted to obtain a uniform sintering behavior. The sintering kinetics can be set uniformly by adjusting the coloring solution 107.

[0073] By adding a sintering activator or a sintering inhibitor to the coloring solution in a targeted manner, the sintering behavior of each layer can be adjusted. Sintering activators such as Zn 2+ 、Al 3+ or Mg 2+ ions, which can be in the form of soluble salts (such as Zn(NO 3 ) 2 *6H 2O, Al(NO 3 ) 3 *9H 2 O or Mg(NO 3 )*H 2 O) is added to the coloring solution. The sintering inhibitor is, for example, La 3+ or Y 3 + , which can be added to the coloring solution in the form of a soluble salt (e.g., La(NO 3 ) 3 *9H 2 O or Y(NO 3 ) 3 *6H 2 O).

[0074] All features explained and shown in connection with the various embodiments of the present invention can be provided in different combinations in the subject matter of the present invention in order to achieve their advantageous effects simultaneously.

[0075] All method steps can be implemented by means suitable for performing the respective method steps. All functions performed by the features of the subject matter can be method steps of a method.

[0076] The scope of protection of the present invention is given by the claims and is not limited to the features explained in the description or shown in the drawings.

[0077] List of reference numerals

[0078] 100 Dental prosthesis

[0079] 101 Dentin core

[0080] 103 Tooth enamel

[0081] 105 Tooth

[0082] 107 Coloring solution

[0083] 108 Alkaline solution

[0084] 109 Slurry

[0085] 110 Support material

[0086] 111-1, 111-2, 111-3, 111-4 Print heads

[0087] 115 Intermediate region

[0088] 117-1, 117-2, 117-n Layers

[0089] 119-1, 119-2 Receiving containers

[0090] 200 production device.

Claims

1. A method for producing a dental restoration by jet printing, comprising the following steps: - printing one or more layers of the dental restoration by means of ceramic slurry jetting; as well as - Jet printing a colouring solution onto the one or more layers.

2. The method according to claim 1, wherein: The one or more layers are dried prior to jet printing the coloring solution.

3. A method according to any one of the preceding claims, wherein: The applied coloring solution is fixed with the aid of an alkaline solution.

4. A method according to any one of the preceding claims, wherein: The ceramic slurry has an alkaline pH.

5. The method according to claim 4, wherein: The coloring solution is fixed by contacting with the ceramic slurry.

6. The method according to claim 4 or 5, wherein: The one or more wet layers are dried together with the applied coloring solution.

7. A method according to any one of the preceding claims, wherein: The steps for producing the dental restoration are repeated.

8. A method according to any one of the preceding claims, wherein: Prior to the sintering process, the produced dental restoration is subjected to a drying and / or degreasing step.

9. A method according to any one of the preceding claims, wherein: The dental restoration is sintered in a sintering furnace.

10. A production device for producing a dental restoration by jet printing, comprising: - a first print head for jet printing one or more layers of the dental restoration by means of a ceramic slurry; as well as - a second print head for jet printing a colouring solution onto the one or more layers.

11. The production device according to claim 10, wherein: The production device includes a holding container for the slurry and a holding container for the coloring solution.

12. The production device according to claim 10 or 11, wherein: The first print head and the second print head are integrated in a common printing module.

13. The production device according to any one of claims 10 to 12, wherein: The first print head and the second print head are independently controllable.

14. The production device according to any one of claims 10 to 13, wherein: The production device comprises a dithering module for calculating intermediate color values ​​by mixing at least two coloring solutions.

15. The production device according to claim 13, wherein: The dithering module is configured to use different two-dimensional dithering patterns in successive layers of the dental restoration.

16. Inkjet printing system, including: - a production device for producing dental restorations by inkjet printing; - at least one ceramic slurry for jet printing one or more layers of said dental restoration; as well as - A colouring solution for jet printing onto the one or more layers.

17. The jet printing system according to claim 16, wherein: The at least one ceramic slurry and / or coloring solution is stored in a container.

18. The jet printing system according to claim 17, wherein: The container is replaceable.

Images