Dental composite ceramic material and method of preparation

Abstract

The application discloses a kind of dental composite ceramic materials and preparation method, it is related to dental ceramic material technical field, the preparation method includes the following steps: zirconium oxide powder is mixed with ethyl silicate solution, and then is dried and pressed into block and high-temperature sintering, obtain dense zirconium oxide;Lithium-based glass powder is used to high-temperature permeation to the zirconium oxide, and then is carried out two-stage heat treatment, so that the lithium silicate glass that remains in the surface of zirconium oxide and penetrates into surface layer is crystallized to form lithium disilicate crystal, obtain dental composite ceramic material.The dental composite ceramic material of the application has excellent mechanical properties of zirconia ceramic and good optical properties of lithium disilicate glass ceramic simultaneously, compared with the weak binding force at interface of traditional zirconia-ceramic veneer double-layer structure and the low strength of ceramic veneer, the wide range of composite is formed between zirconia and lithium disilicate glass ceramic in this material, there is no interface, and the binding force is higher, it is a new type of dental ceramic material with great application potential.

Description

[0001] The application relates to the technical field of dental ceramic materials, and particularly relates to a dental composite ceramic material and a preparation method. BACKGROUND

[0002] Dental zirconia ceramic has excellent mechanical properties due to a phase transformation toughening mechanism, can be safely used as a dental restoration material due to stable chemical properties and good biocompatibility, and is one of the most widely used dental restoration materials for dental defects. However, the zirconia has poor permeability, and direct application cannot meet the aesthetic requirements of patients for the restoration. At present, a common restoration method is to use dense sintered zirconia as a restoration base to provide strength support, and to melt a veneer with excellent optical permeability on the surface of the zirconia to improve the aesthetic effect. However, the veneer has low strength and poor bonding effect with the zirconia, and thus is prone to cracking or peeling during use, resulting in a high clinical restoration failure rate.

[0003] Compared with the zirconia, lithium disilicate glass ceramic has comparable optical properties to the veneer, can meet the aesthetic requirements of the restoration, and can be directly used for aesthetic restoration of anterior teeth without melting a veneer on the surface. Meanwhile, the lithium disilicate glass ceramic has a strength much higher than that of the veneer, and can effectively avoid cracking and peeling during use. However, compared with the zirconia, the mechanical properties of the lithium disilicate glass ceramic are still insufficient to manufacture a multi-unit restoration, and the lithium disilicate glass ceramic is currently mainly used for single crown restoration. Therefore, the zirconia is still needed as a base to provide reliable strength support for the multi-unit restoration.

[0004] In summary, if the lithium disilicate glass ceramic and the zirconia ceramic can be compounded, the excellent mechanical properties of the zirconia and the good optical properties of the lithium disilicate glass ceramic can be combined, and a dental composite ceramic material with both strength and aesthetic properties can be obtained. However, since the zirconia has stable chemical properties, and the preparation schemes and processes of the two are quite different, there is no related report on the composite ceramic material at present. SUMMARY

[0005] The application provides a dental composite ceramic material and a preparation method, so as to solve the technical problems of poor aesthetic properties of the existing dental zirconia ceramic, cracking and peeling of the veneer, and insufficient strength of the lithium disilicate glass ceramic.

[0006] In a first aspect, the application provides a preparation method of a dental composite ceramic material, and the preparation method comprises the following steps:

[0007] The zirconia powder is mixed with a tetraethyl orthosilicate solution, and then is dried, pressed into a block and sintered at a high temperature to obtain dense zirconia.

[0008] The lithium-based glass powder is used to infiltrate the zirconia at high temperature, and then two-stage heat treatment is carried out, so that the lithium disilicate crystals are formed by crystallizing the silicon-lithium glass remaining on the surface of the zirconia and infiltrated into the surface layer, and a dental composite ceramic material is obtained.

[0009] The dental composite ceramic material comprises a zirconia layer, a lithium disilicate glass ceramic layer, and a composite layer with gradually changing composition between the zirconia layer and the lithium disilicate glass ceramic layer.

[0010] Further, the step of obtaining the dense zirconia by mixing the zirconia powder with the tetraethyl orthosilicate solution, then drying and pressing into a block, and high-temperature sintering comprises the following processes:

[0011] The water, ethanol, 28% ammonia water by weight, and zirconia powder are mixed, and magnetic stirring is carried out at a speed of 200-300 r / min for 1-2 h to obtain a mixed solution;

[0012] The tetraethyl orthosilicate is added to the mixed solution at a mass ratio of 1:3-30, and the mixed powder is obtained after magnetic stirring for 5-7 h and drying;

[0013] The mixed powder is pressed into a tablet by a tablet press at a pressure of 20-80 MPa, and then heated to 1400-1500℃ in a high-temperature electric furnace and kept for 1-3 h to obtain the dense zirconia.

[0014] Further, the mass ratio of the water, the ethanol, the 28% ammonia water by weight, and the zirconia powder is 1:5:6:4.

[0015] Further, the heating temperature in the high-temperature electric furnace is 1450℃, and the holding time is 2 h.

[0016] Further, the step of obtaining the dental composite ceramic material by infiltrating the zirconia with the lithium-based glass powder at high temperature, and then carrying out two-stage heat treatment to form lithium disilicate crystals by crystallizing the silicon-lithium glass remaining on the surface of the zirconia and infiltrated into the surface layer comprises the following processes:

[0017] The lithium-based glass powder and deionized water are mixed into a slurry at a weight ratio of 1:(1.5-2.5), and the slurry is coated on the surface of the dense zirconia at a thickness of 0.1 g / cm 2 ~0.4 g / cm 2 The zirconia-silicon-lithium glass composite material is obtained after heating to 1200-1500℃ and keeping for 1-3 h, and then cooling after high-temperature infiltration is completed;

[0018] The zirconium oxide-silicon lithium glass composite material is heated from room temperature to 600-750 DEG C and kept for 1-3 hours, and then heated to 800-950 DEG C and kept for 1-3 hours, so that the lithium disilicate crystals are formed by crystallizing the silicon lithium glass remaining on the surface of the zirconium oxide and infiltrating into the surface layer, and the dental composite ceramic material is obtained.

[0019] Further, the Li:Si in the lithium-based glass powder is 2:1.

[0020] Further, the temperature of the high-temperature infiltration is 1300 DEG C, and the time is 2 hours.

[0021] In the second aspect, the application provides a dental composite ceramic material prepared by the preparation method in any one of the first aspect.

[0022] Compared with the prior art, the application has at least the following beneficial effects:

[0023] 1. Aesthetics: the optical performance of the lithium disilicate glass ceramic layer is far superior to that of pure zirconia ceramic, and is equivalent to that of a veneer, so that the veneer does not need to be fused on the surface of the composite ceramic material to meet the aesthetic requirements of the restoration.

[0024] 2. Strength: the lithium disilicate glass ceramic layer in the dental composite ceramic material has a mechanical property far higher than that of the veneer, which can effectively avoid the veneer collapse of the restoration caused by insufficient strength of the veneer, and the zirconia layer meets the strength requirements of the multi-unit restoration.

[0025] 3. Bonding strength: a large range of transition layer is formed between the zirconia layer and the lithium disilicate glass ceramic layer, there is no interface, and the bonding strength is higher, which can effectively avoid the veneer peeling caused by insufficient bonding strength between the zirconia and the veneer.

[0026] In summary, the application discloses a new dental ceramic material which has excellent mechanical properties of zirconia and good optical properties of lithium disilicate glass ceramic, and has great application potential. BRIEF DESCRIPTION OF DRAWINGS

[0027] The drawings incorporated into the specification and forming a part thereof, illustrate embodiments consistent with the application and, together with the specification, serve to explain the principles of the application.

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced as follows, and obviously, other drawings can also be obtained by those skilled in the art without creative labor.

[0029] Figure 1A flow chart of a preparation method of a dental composite ceramic material provided in the embodiments of the present application is shown in the figure;

[0030] Figure 2 An SEM (scanning electron microscope) image of a zirconia-silicon lithium glass composite layer of zirconia treated by lithium-based glass powder infiltration provided in the embodiments of the present application is shown in the figure;

[0031] Figure 3 An SEM image of a zirconia-lithium disilicate glass ceramic composite layer in a dental composite ceramic material provided in the embodiments of the present application is shown in the figure;

[0032] Figure 4 An SEM image of a lithium disilicate glass ceramic layer in a dental composite ceramic material provided in the embodiments of the present application is shown in the figure. DETAILED DESCRIPTION

[0033] To make the objectives, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described below in connection with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of protection of the present application.

[0034] Unless otherwise specified, all the various raw materials, reagents, instruments and equipment used in the present application can be purchased from the market or prepared by existing methods.

[0035] Embodiments 1-4 provide a dental composite ceramic material and a preparation method, as shown in the figure, zirconia powder is mixed with tetraethyl orthosilicate solution, then dried, pressed into blocks and sintered at high temperature to obtain dense zirconia. Figure 1

[0036] Lithium-based glass powder is used to infiltrate the zirconia at high temperature, and then two-stage heat treatment is performed to crystallize the silicon lithium glass remaining on the surface of the zirconia and infiltrated into the surface layer to form lithium disilicate crystals, thereby obtaining a dental composite ceramic material.

[0037] The dental composite ceramic material includes a zirconia layer, a lithium disilicate glass ceramic layer and a composite layer with gradual change of composition between the zirconia layer and the lithium disilicate glass ceramic layer; and specifically includes the following processes:

[0038] Tetraethyl orthosilicate is quickly added to the mixed solution at a mass ratio of 1:3-30, and the mixed powder is obtained after magnetic stirring for 6 h and drying. The powder is pressed into shape by a tablet press with a pressure of 20-80 MPa, heated to 1400-1500 ℃ in a high-temperature electric furnace and then kept for 1-3 h to obtain dense zirconia. ​

[0039] Li-based glass powder with Li:Si=2:1 was mixed with deionized water in a mass ratio of 1:2 to form a slurry, and the slurry was coated on the surface of the dense zirconia at a thickness of 0.1 g / cm 2 ~ 0.4 g / cm 2 The dense zirconia was stacked on the surface of the dense zirconia, heated to 1200-1500°C and held for 1-3 h, and then cooled to obtain a zirconia-silicon lithium glass composite material. The composite material was heated from room temperature to 600-750°C and held for 1-3 h, and then heated to 800-950°C and held for 1-3 h, and the lithium disilicate crystal was formed by crystallization of the lithium disilicate glass, to obtain a zirconia-lithium disilicate glass-ceramic composite material (i.e., a dental composite ceramic material).

[0040] The specific parameters in the preparation method of the dental composite ceramic material provided in Examples 1-4 are shown in Table 1.

[0041] Table 1

[0042]

[0043] Test Example

[0044] In this example, the dental composite ceramic material obtained in Examples 1-4 was characterized and tested, and the test results are as follows. As can be seen from Figure 2 , Figure 3 and Figure 4 ,

[0045] 1. Strength performance test

[0046] A dental composite ceramic material with a thickness of 1.5 mm was prepared according to the method described in Examples 1-4, wherein the thickness of the dense zirconia was 1 mm, and the thickness of the composite layer and the lithium disilicate glass-ceramic layer was 0.5 mm.

[0047] Comparative Example: A zirconia-porcelain double-layer ceramic structure with a thickness of 1.5 mm was prepared using a traditional manual stacking method, wherein the thickness of the dense zirconia was 1 mm, and the thickness of the surface porcelain was 0.5 mm.

[0048] A vertical load test was performed on the glass-ceramic layer / porcelain layer using a universal mechanical testing machine, a 1 mm diameter circular loading head was selected, and the loading speed was 0.5 mm / min until the glass-ceramic layer / porcelain layer cracked, and the corresponding load was recorded.

[0049] 2. Bonding performance test

[0050] A dental composite ceramic material with a size of 12x3x3 mm was prepared according to the method described in Examples 1-4, wherein the thickness of the dense zirconia was 10 mm, and the thickness of the composite layer and the lithium disilicate glass-ceramic layer was 2 mm.

[0051] Comparative Example: Reference to Comparative Examples 1-4, a 2 mm thick veneer was applied to the surface of a dense zirconia having a thickness of 10 mm to obtain a zirconia-veneer bilayer structure having a total thickness of 12 mm.

[0052] A load test was performed along the interface between the glass-ceramic layer / veneer layer and the zirconia using a universal mechanical testing machine, a 1 mm wide strip-shaped loading head was selected, and loading was performed at a speed of 0.5 mm / min until the glass-ceramic layer / veneer layer and the zirconia were separated by fracture, and the corresponding values were recorded as shown in Table 2.

[0053] Table 2

[0054] Item Strength detection breaking load (N) Bonding force detection breaking load (N) Example 1 49.5±3.7 327.5±25.5 Example 2 52.5±4.1 351.5±43.7 Example 3 62.0±4.6 361.0±29.6 Example 4 53.5±5.3 334.0±48.4 Comparative example 30.0±5.7 240.5±49.5

[0055] Various embodiments of the present application can exist in a range of forms; it should be understood that the description in a range form is merely for the convenience and brevity, and should not be construed as a hard limitation on the scope of the present application; therefore, it should be considered that the range described has been specifically disclosed all possible sub-ranges and single values within the range. For example, it should be considered that the range description from 1 to 6 has been specifically disclosed sub-ranges, such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., as well as single numbers within the range, such as 1, 2, 3, 4, 5, and 6, regardless of the range. In addition, whenever a numerical range is indicated in this document, it refers to any cited number (fraction or integer) within the indicated range.

[0056] In this document, the orientation words such as "upper" and "lower" are specific to the orientation of the drawing surface in the drawings, unless otherwise stated. In addition, in the description of the present application, the terms "include", "contain" and the like mean "include but are not limited to". In this document, relational terms such as "first" and "second" and the like are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between the entities or operations. In this document, "and / or" describes the relationship between the associated objects, which means that there can be three relationships, for example, A and / or B can mean that A exists alone, A and B exist together, and B exists alone. Where A and B can be singular or plural. In this document, "one or more" means one or more, and "multiple" means two or more. "At least one", "at least one of the following", or the like, means any combination of the items, including single items or combinations of multiple items. For example, "at least one of a, b, or c", or "at least one of a, b, and c", can mean a, b, c, a-b (i.e. a and b), a-c, b-c, or a-b-c, where a, b, and c can be single or multiple.

[0057] The foregoing detailed description of the application has been presented for purposes of illustration and description. Various modifications and changes can be made to these embodiments without departing from the spirit and scope of the application. It is intended that the scope of the application should not be limited by the particular representative embodiments described above. Rather, the general scope of the application is to be determined by the appended claims and their equivalents.

Claims

1. A method for producing a dental composite ceramic material, characterized in that The preparation method comprises the following steps: water, ethanol, ammonia water with a weight concentration of 28%, and zirconium oxide powder are mixed, and magnetic stirring is performed at a rotating speed of 200-300 r / min for 1-2 h to obtain a mixed solution; tetraethyl orthosilicate is added into the mixed solution at a mass ratio of 1:3-30, and the mixture is dried after magnetic stirring for 5-7 h to obtain a mixed powder; the mixed powder is pressed into a compact by a tablet machine at a pressure of 20-80 MPa, and then heated to 1400-1500 ℃ in a high-temperature electric furnace and kept for 1-3 h to obtain dense zirconia; lithium-based glass powder is used for high-temperature infiltration of the zirconia, and then two-stage heat treatment is performed to crystallize the silicon-lithium glass remaining on the surface of the zirconia and infiltrated into the surface layer to form lithium disilicate crystals, thereby obtaining a dental composite ceramic material; the dental composite ceramic material comprises a zirconia layer, a lithium disilicate glass ceramic layer, and a composite layer with a gradual change in composition between the zirconia layer and the lithium disilicate glass ceramic layer.

2. The method of producing a dental composite ceramic material according to claim 1, characterized in that, The mass ratio of the water, the ethanol, the ammonia water with a weight concentration of 28%, and the zirconium oxide powder is 1:5:6:

4.

3. The method for preparing dental composite ceramic material according to claim 1, characterized in that, The heating temperature in the high-temperature electric furnace is 1450 ℃, and the holding time is 2 h.

4. The method for preparing dental composite ceramic material according to claim 1, characterized in that, The step of using lithium-based glass powder for high-temperature infiltration of the zirconia and then performing two-stage heat treatment to crystallize the silicon-lithium glass remaining on the surface of the zirconia and infiltrated into the surface layer to form lithium disilicate crystals, thereby obtaining a dental composite ceramic material, comprises the following process: The lithium-based glass powder and deionized water are mixed in a weight ratio of 1: (1.5-2.5) into a slurry, and the slurry is applied to the surface of the dense zirconia at a thickness of 0.1 g / cm 2 0.4 g / cm 2 The glass infiltration treatment is performed by stacking the dense zirconia on the surface of the dense zirconia, heating to 1200-1500 °C and holding for 1-3 h, and then cooling after the high-temperature infiltration is completed, to obtain a zirconia-silicon lithium glass composite material. the zirconia-silicon-lithium glass composite material is heated from room temperature to 600-750 ℃ and kept for 1-3 h, and then heated to 800-950 ℃ and kept for 1-3 h, so that the silicon-lithium glass remaining on the surface of the zirconia and infiltrated into the surface layer is crystallized to form lithium disilicate crystals, thereby obtaining a dental composite ceramic material.

5. The method of producing a dental composite ceramic material according to claim 4, characterized in that, The temperature of the high-temperature infiltration is 1300 ℃, and the time is 2 h.

6. A dental composite ceramic material, characterized in that, The dental composite ceramic material is obtained by the preparation method of any one of claims 1-5.

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