Method for producing a dental multi-coloured glass-ceramic blank, multi-coloured glass-ceramic blank

Abstract

To provide a method for producing a multicolored glass-ceramic blank.SOLUTION: The dental glass ceramic blank (10) is produced from a first material powder (18) and a second material powder (20), wherein the first material powder and the second material powder have different colors, and wherein at least one of the first material powder and the second material powder comprises nanoparticles (14) and / or glass ceramic particles (16). In the course of the method, a first material powder and a second material powder are introduced into the mold 22 in order to form a powder mixture agglomerate 26. The powder mixture aggregate 26 is compacted by hot pressing to form a glass-ceramic blank. Furthermore, the invention relates to a multicoloured glass-ceramic blank. The invention relates to the use of a multicoloured glass-ceramic blank as dental material.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a method for producing a polychrome dental glass-ceramic blank. [Background technology]

[0002] The invention also relates to a multicolored glass-ceramic blank obtained by such a method. do.

[0003] The invention further relates to the use of such polychrome glass ceramic blanks as dental materials. Regarding.

[0004] In this connection, the use of glass ceramic blanks in dental technology is known. Colored glass ceramic blanks are more similar to natural tooth material, especially compared to single-colored glass ceramic blanks. The advantage is that the optical properties of the material can be reproduced very well. The blank is a highly aesthetically demanding dental material with excellent optical and mechanical properties. The optical properties in this case are not only the color but also the characteristics of the dental restorations. It also affects the translucency of the restoration. Summary of the Invention [Problem to be solved by the invention]

[0005] The object of the present invention is to further improve the known method for producing multicolored glass-ceramic blanks. More specifically, the multicolored glass ceramic blanks are produced in a readily manufacturable manner. It is possible to reproduce natural tooth materials very well, and ultimately achieve the desired dental restoration. It can be easily shaped by machine and has excellent mechanical and optical properties after molding. Easily produce multicolored glass-ceramic blanks that can be transformed into dental restorations The aim is to provide a possible method. [Means for solving the problem]

[0006] This problem is solved by a method for producing a multicolored dental glass ceramic blank. The lath ceramic blank is manufactured from at least a first material powder and a second material powder, The first material powder and the second material powder have different colors. At least one of the particles comprises nanoparticles and / or glass ceramic particles. A first powder material and a second powder material are introduced into a mold to form at least one powder mixture agglomerate. and compressing the powder mixture aggregate by hot pressing to obtain a glass forming a ceramic blank.

[0007] The method of the present invention includes several variations.

[0008] In a first variant of the method of the invention, the first material powder and the second material powder are each dried. Optionally, the first material powder and / or the second material powder are introduced into the mold in a pelletized state. In this case, the first material powder and the second material powder have different optical properties. and are metered into the mold to provide a defined sequential progression, in particular a sequential color progression. In this modified example, a powder formed from the first material powder and the second material powder is further The mixed aggregate is directly processed by hot pressing to obtain a glass-ceramic blank. Optionally, the powder mixture agglomerates can be processed through an intermediate step of heat treatment. In an intermediate step of the heat treatment, the glass ceramic blank is obtained. At least one component in the powder mixture agglomerate that is not required for the ceramic blank is thermally removed. For example, in this connection the binder can be removed by heat treatment. It will be removed.

[0009] In a second variant of the method of the invention, the powder of the first material and / or the powder of the second material is a suspension The suspension is in particular an aqueous suspension of powder of the first material and / or powder of the second material. In this variant, the powder mixture agglomerates are glass-ceramic blocks. It must always be dried before it is further processed to obtain rank. If necessary, a drying step is carried out. The dried powder mixture agglomerate is then It is then directly further processed to obtain a blank. As mentioned above in relation to the first variant In the second variant, the intermediate step for producing a green body (unsintered compact) is also It is possible to provide intermediate steps for producing the casing and / or the body in white.

[0010] In the third modification, the first material powder and the second material powder are The green body is introduced into the mold in the form of a green body containing the powder. In this context, powder mixture agglomerates are formed by green bodies. can be.

[0011] In the fourth modification, the first material powder and the second material powder are In this case, the body-in-white is introduced into the mold as a pre-prepared In this variant, the powder mixture agglomerates are formed by a body-in-white. It is done.

[0012] In all variants, the first material powder and / or the second material powder may be nanoparticles and / or Glass ceramic particles are included. This includes nine variations. Variation A In Variation B, the powder of the first material includes nanoparticles. In Variation B, the powder of the second material includes nanoparticles. In Variant C, both the first material powder and the second material powder contain nanoparticles. In the modification E, the first material powder contains glass ceramic particles. In variant F, both the first material powder and the second material powder contain glass ceramic particles. In variation G, the powder of the first material is a mixture of nanoparticles and glass ceramic particles. In Variant H, the powder of the second material contains both nanoparticles and glass ceramic particles. In Variation I, both the first material powder and the second material powder are included. includes nanoparticles and glass ceramic particles.

[0013] In contrast to the prior art, in any of the above-described modifications A to I, the first material powder and the second material powder are In this case, the first material powder and / or the second material powder are not both composed of glass powder. It is of course not excluded that the second material powder also includes glass powder. The use of molecules and / or nanoparticles simplifies the production of glass-ceramic blanks. The glass-ceramic particles already contain nucleation and / or crystallization sites, It is stable up to a certain temperature even under pressure. Therefore, compression may occur earlier than expected. This eliminates the possibility of unwanted gas contamination. In other words, they provide a relatively large surface area for a given volume. Therefore, the crystal structure can be formed in a relatively short time. In this way, the glass-ceramic particles and / or nanoparticles can be easily fused to other phases at a later stage. They are chosen to facilitate or actually enable the manufacturing process, as they provide nuclei for crystallization. Alternatively or additionally, the glass ceramic particles and / or nanoparticles may be have a desirable effect on the optical and / or mechanical properties of the glass-ceramic blank. In particular, glass ceramic particles and / or nanoparticles may be used, to provide a desired color progression and / or a desired translucency progression in the glass-ceramic blank; Furthermore, the glass ceramic particles and / or nanoparticles can provide the desired milky white color. It is possible to create a progression and / or a desired fluorescence progression. The glass ceramic particles and / or nanoparticles have suitable opalescent properties and / or suitable fluorescent properties. In this way, the optical properties of natural teeth can be reproduced particularly well. It is possible.

[0014] Nanoparticles in this specification are understood to mean particles having a diameter between 1 nm and 100 nm. can be.

[0015] In the context of the present invention, glass-ceramic particles include nucleated glass-ceramic particles and It is understood that this means that both crystallized glass-ceramic particles and glass-ceramic particles are included.

[0016] The glass-ceramic particles have a particle size of more than 100 nm and less than 2 mm.

[0017] In one embodiment, the first material powder and the second material powder are mixed in a mold with a locally different mixing ratio. This results in a color progression in the glass-ceramic blank. A continuous color progression can be easily and reliably produced in glass-ceramic blanks. The color progression may also vary locally within the glass-ceramic blank. As the powder is introduced into the mold, the color progression can be very precisely controlled.

[0018] In one variant, the powder mixture agglomerates are heat treated. This is particularly true for glass ceramics. This can be useful for thermally removing components in the powder mixture agglomerates that are undesirable for the block blank. This is also called baking. For example, such heat treatment can cause the powder mixture to solidify. It is possible to remove the binder from the aggregate. Furthermore, the heat treatment causes pre-sintering. It is possible.

[0019] In one variation, at least one of the first powder material and the second powder material is rounded. rounded glass particles, rounded nanoparticles, and / or rounded glass ceramics In this context, rounding includes glass particles, nanoparticles and / or glass This improves the free flow of ceramic particles, which is why the non-rounded particles This is particularly true in comparison. Rounding is performed by introducing the first material powder and the second material powder into a mold. This makes it easier to directly introduce the first and second powder materials into the mold. Therefore, it is particularly useful for preparing a green body and / or a body in white. This allows the preparation process to be omitted, which makes it possible to manufacture glass ceramic blanks more easily. The method is simplified.

[0020] The glass particles, nanoparticles and / or glass ceramic particles may be rounded, for example, mechanically. In this connection, glass particles, nanoparticles and / or glass ceramic particles may be used. Alternatively or additionally, glass particles, nanoparticles and / or The glass-ceramic particles can be thermally rounded. The particles, nanoparticles and / or glass-ceramic particles may be subjected to a plasma treatment.

[0021] In the context of the present invention, the glass particles used are glass ceramics produced by the fusion casting method. This may be a material system for forming lithium disilicate and / or metasilica. Suitable for forming lithium oxide.

[0022] The glass-ceramic particles may be selected from the group of glass particles mentioned above at different crystallization stages: It is possible to use compositions that are already crystallized. These may optionally contain pigments, e.g. The fluorescent pigments may include strontium aluminate doped with yttrium. Rhodium-doped strontium aluminate is disclosed in patent document 1 (European Patent Application Publication No. 36 No. 96150, which is incorporated herein by reference.

[0023] In the context of the present invention, the nanoparticles may also be pigments or opacifiers.

[0024] Furthermore, nanoparticles act as defects in the microstructure and act as catalysts in ceramic compositions to tailor processing properties. Examples of these include zirconium dioxide, aluminum oxide, Examples of silica include various modifications of silicon dioxide.

[0025] In addition, nanoparticles can be used as nucleating agents for heterogeneous nucleation (e.g., metal colloids, It is also possible for the crystal to take the form of other external crystals.

[0026] Furthermore, with regard to nanoparticles, particularly small particles from the group of glass particles or glass ceramic particles are preferred. It is also possible to use an electron beam, which helps to improve sinterability.

[0027] In the compression of powder mixture aggregates by hot pressing, the powder mixture aggregates are placed in a mold. That is, the hot pressing can be performed by mixing the first material powder to form a powder mixture agglomerate. The method of the present invention is therefore carried out in a mold into which a powder of the first material and a powder of the second material are introduced. and a second material powder is introduced and hot pressing is applied using only a single mold. This allows the method to proceed particularly efficiently.

[0028] When the powder mixture aggregate is compressed by hot pressing, the powder mixture aggregate first Both can be heated to a temperature of 700°C and then subjected to a compressive force. The powder mixture is heated to 700°C, which ensures degassing of the powder mixture. Only afterwards can the compressive force be applied. In this way, high quality glass It is possible to produce a ceramic blank. This is particularly the case when a powder of a first material and a powder of a second material are mixed. The raw material powder is introduced directly into the mold to form the green body and / or the white body. This is the case when intermediate steps for the purpose of

[0029] Achieving a temperature of at least 700°C is used as the trigger criterion for applying the compressive force. Therefore, the powder mixture agglomerate is monitored with respect to its temperature. It is based on the finding that the powder mixture agglomerates are sufficiently degassed when a temperature of 700°C is reached. In this way, the whole process and especially the hot pressing can be easily and reliably controlled. It is possible.

[0030] The powder mixture agglomerate is preferably hot-pressed to form a matrix of the first material powder and / or a second material powder. The two powder materials are compressed to a density of at least 99.9% of the base material density. The glass ceramic blank after compaction is a matrix of the first material powder and / or the second material powder. In this way, a glass having high mechanical quality can be obtained. A lath ceramic blank can be produced.

[0031] In one embodiment, a first material powder is mixed to form at least two powder mixture agglomerates. The powder of the first material and the powder of the second material are introduced into at least two separate locations in the mold. Using such a mold, at least two glass-ceramic particles can be obtained, one from each powder mixture agglomerate. Using such a mold, it is possible to manufacture a glass blank. Since it is possible to simultaneously produce a metal blank, such a mold is also called a multiple mold. In this way, a relatively large number of glass ceramic blanks can be produced in a relatively short time. It can be made.

[0032] Generally speaking, therefore, the method of the present invention is thus applicable to the production of a single mold, i.e., a single glass cell. In combination with a mold or multiple molds designed to produce a ceramic blank This can be implemented in the same way.

[0033] The compression of the powder mixture aggregate by hot pressing is performed at 650°C to 980°C, especially 700°C to 750°C, and The pressure can be particularly 5 MPa to 50 MPa, and preferably 10 MPa to 30 MPa. The result is a glass-ceramic blank of high mechanical and optical quality. Sometimes the temperature is too low from a material-specific point of view, and therefore does not allow compression or gas insufficiency. Temperatures that would result in undesired inclusions are avoided. Similarly, materials that may result in undesired crystal formation are avoided. The excessively high temperatures inherent are also avoided.

[0034] The powder mixture agglomerate is compressed by hot pressing for 0.1 to 10 minutes, preferably 0.3 to 5 minutes. That is, the molding by hot pressing can be completed in a relatively short time. In this case, it is possible to produce a glass ceramic blank in a relatively short time. It goes without saying that the mechanical and optical requirements for the ceramic blank are met simultaneously. do not have.

[0035] The compression of the powder mixture agglomerate by hot pressing is less than 0.1 bar, preferably 0.01 to 0.08 bar. In simple terms, hot pressing can be performed at atmospheric pressure. The condensation is carried out under reduced pressure, which reduces undesired reactions with the surrounding atmosphere or This also protects the type.

[0036] In one variant, the glass ceramic blank is a multi-layer blank. The glass ceramic blank is designed for use in two or more dental restorations This means that the glass-ceramic resin is used before, during or after the fabrication of the dental restoration. This means that the cube must be split into at least two pieces. The ceramic blank can be cut or split, for example. This is preferably done to form a dental restoration. The blank is milled or cut by a milling machine during or after the fabrication of the dental restoration. Separation may also occur in a grinding machine, in which case separation involves removal of material. By producing a large number of blanks, many glass ceramic blanks can be produced efficiently in a short time. Moreover, it is possible to manufacture it reliably.

[0037] The method also includes opening the mold and removing the glass-ceramic blank. In this case, the mold is opened while both the mold and the glass ceramic blank are still hot. In this context, it is also called hot demolding or demolding in a hot state. The glass ceramic blank is then removed by opening the mold. The mold is not cooled in a routine manner before being poured into the mold, which increases the efficiency of mold utilization. The glass ceramic blank is of course then cooled outside the mold.

[0038] The object of the present invention is to provide a polychrome glass-ceramic blank obtainable by the method of the present invention. As already explained, such glass ceramic blanks can be efficiently The glass ceramic blank is manufacturable, which includes particularly cost-effectiveness. Glass ceramic blanks are therefore ideal for the manufacture of dental restorations. In particular, such blanks can be further processed to obtain crowns, abutments, Abutments, crowns, inlays, onlays, veneers, bridges, and The glass ceramic blank can be used to make a bridge denture. Due to its mechanical and optical properties, dental restorations also have good mechanical and optical properties. do.

[0039] In addition, the subject of the present invention is the polychrome glass-ceramic brush of the present invention as a dental material. In particular, the polychrome glass ceramic blank of the present invention can be obtained by using a toothed lump. The glass ceramic blanks have good mechanical properties and are used to fabricate dental restorations. Due to the excellent mechanical and optical properties of the dental restorations, it is possible to produce dental restorations with good mechanical and optical properties. It is possible.

[0040] The invention will now be described with reference to various embodiments shown in the accompanying drawings. [Brief explanation of the drawings]

[0041] [Figure 1] 1 is an illustration of a polychrome glass-ceramic blank of the invention produced by the method of the invention and its use for making a dental restoration. FIG. [Figure 2] 2 is an explanatory diagram showing the sequence of the method of the present invention for producing the polychrome glass ceramic blank in FIG. 1. FIG. [Figure 3] FIG. 3 is an explanatory diagram showing a modified example of the method in FIG. 2. [Figure 4] FIG. 3 is an explanatory diagram showing a further modification of the method in FIG. 2. DETAILED DESCRIPTION OF THE INVENTION

[0042] FIG. 1 shows a multicolored glass-ceramic blank 10 .

[0043] The glass ceramic blank 10 comprises a glass ceramic main phase 12, nanoparticles 14 and glass Both lath ceramic particles 16 are embedded in the main phase 12 .

[0044] In FIG. 1, the nanoparticles 14 and glass ceramic particles 16 are shown merely symbolically and in an excessive manner. is shown in size.

[0045] The glass-ceramic particles 16 are glass-ceramic in that they were already present during the production of the main phase 12. This is different from the main phase 12 of the tetrahedral structure, which will be explained in more detail below.

[0046] The glass ceramic blank 10, i.e. in particular the main phase 12, is made from material powders of different colors. Therefore, the color of the glass ceramic blank 10 progresses continuously. are shown in FIG. 1 by hatching of different widths.

[0047] The glass ceramic blank 10 is used as a dental material for producing a dental restoration R. can be.

[0048] In this connection, a glass ceramic blank 10 is prepared in step (a). The tooth in Figure 1 is machined by removing material to obtain the shape of the dental restoration R. It goes without saying that the dental restorations are shown only diagrammatically.

[0049] In step (b) following step (a), the glass cell processed by removing material is The glass-ceramic blank 10 is heat-hardened. A crystallization process occurs, which establishes the mechanical properties of the glass-ceramic blank 10. will be done.

[0050] The dental restoration R thus produced can then be used on the patient.

[0051] The glass ceramic blank 10 is described below with reference to FIGS. 2, 3 and 4. It is produced by the method.

[0052] In the example according to FIG. 2, in a first method step A, a first powder material 18 and a second powder material 20 are mixed. is introduced into a mold 22.

[0053] The first powder material 18 and the second powder material 20 have different colors.

[0054] The first material powder 18 also contains nanoparticles 14 and glass particles 24 .

[0055] The powder of the second material 20 includes glass-ceramic particles 16 and glass particles 24 .

[0056] In this case, the glass particles 24, the nanoparticles 14, as well as the glass ceramic particles 16 are rounded. It is being done.

[0057] Furthermore, the first material powder 18 and the second material powder 20 are introduced into the mold 22 in locally different mixing ratios. do.

[0058] The glass particles 24, nanoparticles 144, and glass ceramic 16 in FIG. 2 are generally It goes without saying that the figures are shown in a greatly enlarged scale. The glass particles 24 of the first powder 18 are shown as squares, and the glass particles 24 of the second powder 20 are shown as circles. For clarity, only some particles are labeled with reference numbers. .

[0059] In the illustrated embodiment, the powder of the first material 18 is more abundant than the powder of the second material 20 in the lower region of the mold 22. The opposite is true for the upper region of Type 22.

[0060] Since the first powder material 18 and the second powder material 20 are different in color, this means that the first powder material 18 and the second powder material 20 are different in color. and the second material powder 20 into the mold 22. This color progression is maintained in the finished glass-ceramic blank 10. It will be held.

[0061] The powder mixture agglomerate 26 can optionally be compressed into a green body in a mold 22. .

[0062] Additionally, optionally, the powder mixture agglomerate 26 can be heat treated.

[0063] In a subsequent method step B, the powder mixture agglomerate 26 is compressed by hot pressing. In this manner, the glass-ceramic blank 10 is formed from the powder mixture agglomerate 26.

[0064] For this purpose, the powder mixture agglomerate 26 is left in the mold 22 .

[0065] In detail, during the hot pressing process, the powder mixture agglomerate 26 is first heated to 700 Only when the powder mixture agglomerate 26 reaches a temperature of 700°C is the compressive force increased. F is applied to the powder mixture agglomerate 26. In other words, reaching a temperature of 700° C. requires a compressive force F is the trigger criterion for adding

[0066] The compressive force F is selected so that the powder mixture agglomerate 26 is subjected to a pressure of 10 MPa to 30 MPa. In this example, the pressure is 20 MPa.

[0067] Furthermore, the temperature of the powder mixture agglomerate 26 is further increased while the compressive force F is being applied. In this example, the temperature is increased to 730°C.

[0068] In addition, the compression is performed in a vacuum chamber V. The pressure in the vacuum chamber V is 0.01 bar~0.08 bar.

[0069] In the illustrated embodiment, the above pressure and temperature are maintained for 4 minutes.

[0070] Thereafter, in method step C, the mold 22 is opened and the glass ceramic blank 10 is placed in the mold 22. This is essentially done immediately after method step B. There is no cooling operation.

[0071] The opening of the mold 22 in method step C is merely schematic and may be carried out in any other suitable manner. It goes without saying that it can be unlocked in a proper way.

[0072] The glass ceramic blank 10 thus manufactured is a glass ceramic blank 10 having a base material in the first material powder 18. Achieves 99.9% density of the material.

[0073] Regarding the geometric dimensions of the glass ceramic blank 10, the dimensions of the blank are as shown in FIG. 1. A single dental restoration R is made from the glass ceramic blank 10 by the method described above based on 1. These are dimensions that can be manufactured.

[0074] The glass ceramic blank 10 may be a crown blank, an inlay blank, or a bridge blank. Such blanks and corresponding dimensions are known. do.

[0075] For example, the crown blank has dimensions of 18.4 mm x 14.7 mm x 12.5 mm. The blank may have dimensions of 15 mm x 32 mm x 15 mm.

[0076] FIG. 3 shows a variation of the method in FIG.

[0077] In this case, only the differences from the method of FIG. 2 will be explained. are given the same reference numerals.

[0078] The inside of the mold 22 used in the variant according to FIG. 3 is the same as that of the mold 22 used in the method according to FIG. It is essentially twice as large as

[0079] Therefore, in the variant according to FIG. 3, the glass that can be produced by the method of FIG. Manufacture a glass-ceramic blank 10 at least twice as large as the glass-ceramic blank 10. It is possible.

[0080] The dimensions of the glass ceramic blank 10 produced by the method according to FIG. By the method described in 1, two dental restorations R from glass ceramic blanks 10 These are dimensions that can be manufactured.

[0081] Glass ceramic blanks 10 for producing more than two dental restorations R are also conceivable. Needless to say, there is.

[0082] Therefore, the glass ceramic blank 10 that can be produced according to the variant shown in FIG. It can also be called Rank 28.

[0083] A separation surface 30 may be provided within the multi-layer blank 28. The multi-layer blank 28 may include a separation surface 30. When divided along 30, two glass ceramic blanks 10 are obtained, the dimensions of which are shown in FIG. 1 corresponds to a glass ceramic blank 10 obtained by the method according to claim 2.

[0084] FIG. 4 shows a further variant of the method for producing a glass-ceramic blank 10 .

[0085] In this case too, only the differences with the method according to FIG. The elements are labeled with the same reference numbers.

[0086] Again, the difference concerns the type 22 used.

[0087] In the method according to FIG. 4, the mold 22 has two cavities 32, 34 and is made of glass ceramic. The powder mixture 26 for producing the blank 10 is contained in each of the cavities 32, 34. In other words, such a mold 22 allows two glass-ceramic plates to be formed. It is possible to simultaneously manufacture the block 10, the dimensions of which can be obtained by the method according to FIG. It is compatible with glass ceramic blanks 10.

[0088] Therefore, in the variant according to FIG. 4, in method step A, the powder of the first material 18 and the powder of the second material The raw material powder 20 is deposited in at least two separate locations (corresponding to the cavities 32 and 34) within the mold 22. In this way, two separate powder mixture agglomerates 26 are formed.

[0089] Such a mold 22 may also be referred to as a multiple mold 36 .

[0090] The above examples may be combined. In this regard, one possible variant is For example, the present method may be carried out using a multiple die designed to produce two or more multiple blanks. This makes it possible to carry out a process in particular for the simultaneous production of a large number of glass-ceramic blanks. It is possible to create [Prior art documents] [Patent documents]

[0091] [Patent Document 1] European Patent Application Publication No. 3696150 [Explanation of symbols]

[0092] 10 Glass ceramic blanks 12 Main phase 14 Nanoparticles 16 Glass ceramic particles 18 First material powder 20 2nd material powder 22-inch 24 Glass particles 26 Powder mixed aggregate 28 Multiple Blanks 30 separation plane 32 Cavity 34 Cavity 36 Multiplex type F Compression force R Dental restoration V Vacuum Chamber

Claims

1. A multicolored dental glass comprising at least a first powder material (18) and a second powder material (20). A method for manufacturing a ceramic blank (10), comprising: The material powders (20) have different colors, and the first material powder (18) and the second material powder (20) At least one of the particles includes nanoparticles (14) and / or glass ceramic particles (16). said method comprising: - mixing the powder of the first material (18) and the powder of the second material (18) to form at least one powder mixture agglomerate (26); and introducing the second material powder (20) into a mold (22); The glass ceramic is formed by compressing the powder mixture aggregate (26) by hot pressing. forming a ceramic blank (10); A method comprising:

2. 2. The method of claim 1, wherein the first powder material (18) and the second powder material (20) are introduced into the mold (22) in locally different mixing ratios, thereby A progression of colors occurs in rank (10), the way.

3. 3. The method of claim 1 or 2, further comprising the step of heat treating the powder mixture agglomerate (26). The method further comprises:

4. The method according to any one of claims 1 to 3, wherein the powder of the first material (18) and the At least one of the two material powders (20) is a rounded glass particle (24), a rounded glass particle (25), a rounded glass particle (26), a rounded glass particle (27), a rounded glass particle (28), a rounded glass particle (29), a rounded glass particle (30), a rounded glass particle (31), a rounded glass particle (32), a rounded glass particle (33), a rounded glass particle (34), a rounded glass particle (35), a rounded glass particle The glass ceramic particles (16) are made of glass-ceramic nanoparticles (14) and / or glass-ceramic particles (16). Hmm, a method.

5. The method according to any one of claims 1 to 4, wherein the powder mixture is agglomerated by hot pressing. the powder mixed agglomerate (26) is disposed within the mold (22) upon compaction of the agglomerate (26); method.

6. The method according to any one of claims 1 to 5, wherein the powder mixture is agglomerated by hot pressing. During compaction of the agglomerate (26), the powder mixture agglomerate (26) is first heated to a temperature of at least 700°C. A method of applying heat and then applying a compressive force (F).

7. 7. The method of claim 6, wherein the attainment of a temperature of at least 700°C is achieved by the compressive force (F) , which is used as a trigger criterion for adding

8. The method according to any one of claims 1 to 7, wherein the powder mixture agglomerate (26) is The base material of the first material powder (18) and / or the base material of the second material powder (20) are formed by top pressing. A method of compressing material to at least 99.9% of its density.

9. The method according to any one of claims 1 to 8, wherein at least two powder mixed agglomerates ( The first powder material (18) and the second powder material (20) are poured into the mold to form a powder (26). (22) into at least two separate locations within the

10. 10. The method according to any one of claims 1 to 9, wherein the powder mixture agglomerate (26) is mixed with a mixture of 650 ° C. to 780 ° C., in particular 700 ° C. to 750 ° C., and in particular 5 MPa to 50 MPa, preferably 10 MPa to 30 MPa A method of compressing by hot pressing under pressure.

11. The method according to any one of claims 1 to 10, wherein the powder mixture agglomerate (26) is 0. Compressing by hot pressing for 1 to 10 minutes, preferably 0.3 to 5 minutes. 。

12. The method according to any one of claims 1 to 11, wherein the powder mixture agglomerate (26) is 0. Compressing by hot pressing at atmospheric pressure of less than 1 bar, preferably 0.01 to 0.08 bar. 。

13. The method according to any one of claims 1 to 12, comprising the step of: The method is a multiple blank (28).

14. 14. The method according to any one of claims 1 to 13, comprising opening the mould (22) and removing the glass The method further includes removing the ceramic blank (10).

15. A polychrome glass-ceramic plate obtainable by the method according to any one of claims 1 to 14. nk (10).

16. Use of a polychrome glass ceramic blank (10) as dental material according to claim 15. The use of a polychrome glass ceramic blank (10) for producing a dental restoration (R) is particularly For.

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