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US-12617711-B2 - Pre-sintered ceramic block for dental restoration, preparation method therefor and use thereof

US12617711B2US 12617711 B2US12617711 B2US 12617711B2US-12617711-B2

Abstract

Disclosed is a pre-sintered ceramic block for a dental restoration, which has a low pre-sintering temperature, contains a silica main crystal phase, but does not contain or contains a small amount of lithium metasilicate crystal phase. The pre-sintered ceramic block has a low hardness, with a Vickers hardness of 0.5-3 GPa, which is significantly lower than that of a ceramic block containing a lithium metasilicate crystal phase, and same is suitable for dry machining and also wet machining when being machined into a dental restoration.

Inventors

  • Lingling He
  • Guoyi SONG
  • Cheng HOU
  • CHENGWEI HAN
  • Zhongliang ZHAO
  • Jialing Li

Assignees

  • SHENZHEN UPCERA DENTAL TECHNOLOGY CO., LTD.

Dates

Publication Date
20260505
Application Date
20190415

Claims (18)

  1. 1 . A pre-sintered ceramic block for a dental restoration, wherein the pre-sintered ceramic block comprises the following components: SiO 2 : 55-85% wt, Li 2 O: 12-25% wt, ZrO 2 : 0-10% wt, Al 2 O 3 : 0.3-8% wt, La 2 O 3 : 0-7% wt, ZnO: 0-10% wt, K 2 O: 0.1-10% wt, GeO 2 : 0.1-7% wt, nucleating agent: 0-10% wt, colorant: 0-10% wt, and other additives: 0-15% wt; wherein the nucleating agent is one of or a combination of at least two of P 2 O 5 , TiO 2 , V 2 O 5 , Cr 2 O 3 , and Fe 2 O 3 ; the other additives are one of or a combination of at least two of B 2 O 3 , F, Na 2 O, BaO, SrO, CaO, and MgO; and wherein the pre-sintered ceramic block contains a silica main crystal phase, has a Vickers hardness of 0.5-3 GPa, and is opaque.
  2. 2 . The pre-sintered ceramic block according to claim 1 , wherein the pre-sintered ceramic block has a three-point bending strength of 10-110 MPa.
  3. 3 . The pre-sintered ceramic block according to claim 1 , wherein the pre-sintered ceramic block does not contain a lithium metasilicate crystal phase.
  4. 4 . The pre-sintered ceramic block according to claim 1 , wherein the colorant is a glass colorant or a ceramic colorant.
  5. 5 . A method for preparing the pre-sintered ceramic block according to claim 1 , comprising the steps of: (1) preparing a matrix glass powder; (2) putting the prepared matrix glass powder into a mould, and carrying out pressing molding to obtain a matrix glass body; and (3) pre-sintering the matrix glass body under a vacuum condition to obtain the pre-sintered ceramic block, wherein a sintering temperature during pre-sintering is 530-590° C.
  6. 6 . The method for preparing the pre-sintered ceramic block according to claim 5 , wherein the matrix glass powder comprises the following components: SiO 2 : 55-85% wt, Li 2 O: 12-25% wt, ZrO 2 : 0-10% wt, Al 2 O 3 : 0.3-8% wt, La 2 O 3 : 0-7% wt, ZnO: 0-10% wt, K 2 O: 0.1-10% wt, GeO 2 : 0.1-7% wt, nucleating agent: 0-10% wt, colorant: 0-10% wt, and other additives: 0-15% wt; wherein the nucleating agent is one of or a combination of at least two of P 2 O 5 , TiO 2 , V 2 O 5 , Cr 2 O 3 , and Fe 2 O 3 ; the other additives are one of or a combination of at least two of B 2 O 3 , F, Na 2 O, BaO, SrO, CaO, and MgO.
  7. 7 . The method for preparing the pre-sintered ceramic block according to claim 5 , wherein the sintering temperature during pre-sintering is 530-560° C.
  8. 8 . The method for preparing the pre-sintered ceramic block according to claim 5 , wherein a holding time for pre-sintering is 20-240 min.
  9. 9 . A pre-sintered ceramic block for a dental restoration, wherein the pre-sintered ceramic block comprises the following components: SiO 2 : 55-85% wt, Li 2 O: 12-25% wt, ZrO 2 : 0-10% wt, Al 2 O 3 : 0.3-8% wt, La 2 O 3 : 0-7% wt, ZnO: 0-10% wt, K 2 O: 0.1-10% wt, GeO 2 : 0.1-7% wt, nucleating agent: 0-10% wt, colorant: 0-10% wt, and other additives: 0-15% wt; wherein the nucleating agent one of or a combination of at least two of P 2 O 5 , TiO 2 , V 2 O 5 , Cr 2 O 3 , and Fe 2 O 3 , the other additives are one of or a combination of at least two of B 2 O 3 , F, Na 2 O, ZrO 2 , BaO, SrO, CaO, and MgO; and wherein the pre-sintered ceramic block contains a silica main crystal phase, has a Vickers hardness of 0.5-3 GPa, is opaque, and exhibits a gradual transmittance and/or color after dense-sintering of 800-1100° C.
  10. 10 . The pre-sintered ceramic block according to claim 9 , wherein the pre-sintered ceramic block has a three-point bending strength of 10-110 MPa.
  11. 11 . The pre-sintered ceramic block according to claim 9 , wherein the pre-sintered ceramic block does not contain a lithium metasilicate crystal phase.
  12. 12 . The pre-sintered ceramic block according to claim 9 , wherein the colorant is a glass colorant or a ceramic colorant.
  13. 13 . A method for preparing the pre-sintered ceramic block according to claim 9 , comprising the steps of: (1) preparing at least two matrix glass powders with different transmittance and/or color; (2) putting the prepared at least two matrix glass powder into a mould in the order of transmittance and/or color gradient, and carrying out pressing molding to obtain a matrix glass body; and (3) pre-sintering the matrix glass body under a vacuum condition to obtain the pre-sintered ceramic block, wherein a sintering temperature during pre-sintering is 530-590° C.
  14. 14 . The method for preparing the pre-sintered ceramic block according to claim 13 , wherein the matrix glass powder comprises the following components: SiO 2 : 55-85% wt, Li 2 O: 12-25% wt, ZrO 2 : 0-10% wt, Al 2 O 3 : 0.3-8% wt, La 2 O 3 : 0-7% wt, ZnO: 0-10% wt, K 2 O: 0.1-10% wt, GeO 2 : 0.1-7% wt, nucleating agent: 0-10% wt, colorant: 0-10% wt, and other additives: 0-15% wt; wherein the nucleating agent is one of or a combination of at least two of P 2 O 5 , TiO 2 , V 2 O 5 , Cr 2 O 3 , and Fe 2 O 3 ; the other additives are one of or a combination of at least two of B 2 O 3 , F, Na 2 O, BaO, SrO, CaO, and MgO.
  15. 15 . The method for preparing the pre-sintered ceramic block according to claim 13 , wherein the sintering temperature during pre-sintering is 530-560° C.
  16. 16 . The method for preparing the pre-sintered ceramic block according to claim 13 , wherein a holding time for pre-sintering is 20-240 min.
  17. 17 . A method for preparing a ceramic block for a dental restoration, comprising the steps of: preparing the pre-sintered ceramic block of claim 1 ; and dense-sintering the pre-sintered ceramic block under a vacuum condition; wherein a temperature during dense-sintering is 800-1100° C.
  18. 18 . A method for preparing a dental restoration, comprising the steps of: preparing the pre-sintered ceramic block of claim 1 ; processing the pre-sintered ceramic block into a dental restoration shape to obtain a restoration body; and dense-sintering the restoration body under a vacuum condition to obtain a dental restoration; wherein a temperature during dense-sintering is 800-1100° C.

Description

CROSS REFERENCE TO RELATED APPLICATION This application is a national stage application under 35 U.S.C. § 371 of International Patent Application No. PCT/CN2019/082763, filed on Apr. 15, 2019, and entitled “Pre-Sintered Ceramic Block for Dental Restoration, Preparation Method Therefor and Use Thereof.” The entirety of the aforementioned application is incorporated herein by reference. FIELD OF INVENTION The present application relates to the technical field of a dental restoration, in particular to a pre-sintered ceramic block for a dental restoration, a preparation method, and use thereof. BACKGROUND OF THE INVENTION The ChairSide restorative system is a dental restorative system formed by introducing computer-aided design and manufacture into the field of restorative dentistry. The ChairSide restorative system, which is convenient and rapid, and breaks through traditional denture manufacturing procedures such as teeth grinding, mold fabricating, wax carving, and porcelain, allows a 3D camera to directly capture the teeth image immediately after the teeth are ground and trimmed by a dentist, and then transfers the image to the computer in real-time, and processes the ceramic blocks into a dental restoration by the automatic ceramic block grinder with the assistance of the computer. Since the emergence of ChairSide restorative systems, the development of dental restorative materials suitable for ChairSide restorative systems has become the focus of researchers at home and abroad. It has been found that dental restorations made from lithium disilicate glass-ceramic materials have both outstanding aesthetic effects and good mechanical properties. However, lithium disilicate glass-ceramic materials have high hardness and poor processability, making it difficult to apply in ChairSide repair system. In order to solve the problem, the prior art discloses that lithium metasilicate glass ceramics with lithium metasilicate as a main crystal phase are obtained through pre-sintering at a lower temperature, then is subjected to mechanical processing to obtain a restoration shape, and then to dense-sintering at a higher temperature, to finally obtain a glass ceramic restoration with lithium disilicate as a main crystal phase; since the hardness of lithium metasilicate is lower than that of lithium disilicate, the processability is improved. Even so, the Vickers hardness of the ceramic block with lithium metasilicate as the main crystal phase still reaches 5-6 GPa, the ceramic block is only suitable for being machined by a wet method and is not suitable for dry machining, if the lithium metasilicate glass ceramic is machined by a dry method, the problem of incomplete edge or incomplete processing or even the problem of the ceramic block damage may occur, and the machine needle can be easily damaged; therefore, how to develop a pre-sintered ceramic block with lower hardness and suitable for dry machining has become a crucial problem. SUMMARY OF THE INVENTION The present application provides a pre-sintered ceramic block for a dental restoration, which is used for solving the problem that lithium metasilicate glass ceramic has high hardness and not suitable for dry machining. Correspondingly, the present application provides a method of preparing a pre-sintered ceramic block for a dental restoration. The present application also provides a method of preparing a ceramic block for the dental restoration and a method of preparing a dental restoration. Specific technical solutions are as follows: According to a first aspect of the present application, there is provided a pre-sintered ceramic block for a dental restoration, wherein the pre-sintered ceramic block contains a silica main crystal phase, has a Vickers hardness of 0.5-3 GPa, preferably 1-2.5 GPa, and is opaque. In some embodiments of the first aspect of the present application, the pre-sintered ceramic block does not contain a lithium metasilicate crystal phase. In some embodiments of the first aspect of the present application, the pre-sintered ceramic block has a three-point bending strength of 10-110 MPa; preferably 10-90 MPa; more preferably 30-70 MPa. In some embodiments of the first aspect of the present application, the pre-sintered ceramic block comprises the following components: SiO2 55-85% wt, preferably 55-80% wt, more preferably 60-80% wt, most preferably 64-75% wt,Li2O: 10-25% wt, preferably 12-25% wt, more preferably 13-17% wt,ZrO2 0-10% wt, preferably 0-8% wt, more preferably 0-6% wt, most preferably 0-4% wt,Al2O3: 0.3-8% wt, preferably 0.5-6% wt, more preferably 0.5-5% wt, most preferably 0.5-4% wt,La2O3: 0-7% wt, preferably 0-5% wt, more preferably 0-4.5% wt, most preferably 0-4% wt,ZnO: 0-10% wt, preferably 0-8% wt, more preferably 0-7% wt, most preferably 0.1-5% wt,K2O: 0.1-10% wt, preferably 0.1-9% wt, more preferably 0.1-7% wt, most preferably 0.5-4.5% wt,GeO2: 0.1-7% wt, preferably 0.1-6% wt, more preferably 0.3-5% wt, most preferably 0.5-4% wt,