DENTAL GRADIENT COLOR-RESIN CERAMIC RESTORATION MATERIAL AND PREPARATION METHOD THEREOF

Abstract

Disclosed are a dental gradient color-resin ceramic restoration material and a preparation method thereof. The method includes: preparing at least two paste materials with different colors, respectively dispersing the paste materials with different colors at a certain speed and under a vacuum of -0.01-0.1 MPa to obtain at least two granular materials with different colors having an average size of 0.1 mm to 5 mm; spreading the at least two granular materials with different colors to be flat in a mould in sequence to obtain at least two layers, and then tightly combining the at least two layers at a pressure of 0.5-5 MPa to obtain a semi-finished product of a gradient color-resin ceramic restoration material; polymerizing and curing the semi-finished product at 60-200° C. and 2-50 MPa to obtain a multilayer gradient color-resin ceramic restoration material.

Claims

1. A method for preparing a dental gradient color-resin ceramic restoration material, comprising: step 1, preparing at least two paste materials with different colors, and respectively dispersing the paste materials with different colors to obtain at least two granular materials with different colors; step 2, spreading the at least two granular materials with different colors to be flat in a mould in sequence to obtain at least two layers, and then tightly combining the at least two layers to obtain a semi-finished product of a gradient color-resin ceramic restoration material; and step 3, polymerizing and curing the semi-finished product obtained in the step 2 to obtain a multilayer gradient color-resin ceramic restoration material.

2. The method of claim 1, wherein in step 1, each of the paste materials is independently prepared by a process comprising: adding a polymerizable monomer, an initiator, an inorganic filler and a colorant into a mixing device, and stirring to be uniform to obtain the paste material; or adding a polymerizable monomer, an initiator, an inorganic filler and a colorant into a mixing device in batches, and stirring to be uniform to obtain the paste material; and the at least two granular materials with different colors obtained in step 1 each independently have a particle size of 0.1 mm to 5 mm.

3. The method of claim 1, wherein the dispersing in step 1 is conducted at a rotating speed of 20 r/min to 150 r/min, preferably 60 r/min to 120 r/min; the dispersing in step 1 is conducted under a vacuum degree of -0.01 MPa to -0.1 MPa, preferably -0.07 MPa to -0.09 MPa; the tightly combining the at least two layers in step 2 is conducted at a pressure of 0.5 MPa to 5 MPa, preferably 1 MPa to 3 MPa; the polymerizing and curing in step 3 is conducted at a pressure greater than that of the tightly combining the at least two layers in step 2, preferably 2 MPa to 50 MPa, and further preferably 10 MPa to 30 MPa; and the polymerizing and curing in step 3 is conducted at a temperature of 60° C. to 200° C., preferably 100° C. to 150° C.

4. The method of claim 2, wherein a weight ratio of the polymerizable monomer to the inorganic filler in raw materials for preparing the at least two paste materials with different colors is in a range of 10: 90 to 90: 10, preferably 15: 85 to 40: 60; a weight percentage of the initiator to a total amount of the polymerizable monomer and the inorganic filler is in a range of 0.01 wt% to 10 wt%, preferably 0.1 wt% to 5 wt%; and a weight percentage of the colorant to a total amount of the polymerizable monomer and the inorganic filler is in a range of 0.01 wt% to 3 wt%, preferably 0.1 wt% to 1 wt%.

5. The method of claim 1 wherein raw materials for preparing the at least two paste materials with different colors further comprise an additive, and the additive is at least one selected from the group consisting of an accelerator, a crosslinking agent, a fluorescent agent, a polymerization inhibitor, an antibacterial agent, an ultraviolet absorber, an anti-tarnishing agent, a viscosity regulator, a wetting agent, an antioxidant, a stabilizer, and a diluent; and a weight percentage of the additive to a total amount of the polymerizable monomer and the inorganic filler is in a range of 0 wt% to 5 wt%, preferably 0.01 wt% to 1 wt%.

6. The method of claim 1 wherein the polymerizable monomer is a free radical resin monomer, and the free radical resin monomer comprises at least one selected from the group consisting of a monofunctional group-monomer compound, a bifunctional group-monomer compound and a monomer compound with at least three functional groups, wherein the monofunctional group-monomer compound comprises at least one selected from the group consisting of methyl methacrylate, ethyl methacrylate, isobutyl methacrylate, tert-butyl methacrylate, iso-amyl methacrylate, benzyl methacrylate, glycidyl methacrylate, dodecyl methacrylate, tetrahydrofurfuryl methacrylate, 2-(N,N-dimethylamino) ethyl methacrylate, 2,3-dibromopropyl methacrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 6-hydroxyhexyl methacrylate, 10-hydroxydecyl methacrylate, triethylene glycol mono monomethacrylate, propylene glycol monomethacrylate, ethylene glycol methacrylate, diethylene glycol methacrylate, methoxy diethylene glycol methacrylate, polyethylene glycol methacrylate, N-methylol methacrylamide, N-succinyl methyl acrylamide, and 10-methacryloyloxydecyl dihydrogen phosphate; the bifunctional group-monomer compound comprises at least one selected from the group consisting of ethylene glycol dimethacrylate, propylene glycol dimethacrylate, neopentanediol dimethacrylate, butanediol dimethacrylate, hexanediol dimethacrylate, poly(ethylene glycol) dimethacrylate, triethylene glycol dimethacrylate, urethane dimethacrylate, bisphenol A glycerolate dimethacrylate (2,2-bis(4-(3-methacryloyloxy-2-hydroxypropoxy)phenyl)propane), 2,2-bis(4-methacryloyloxyethoxyphenyl)propane, 2,2-bis(4-methacryloyloxydiethoxyphenyl)propane, and 2,2-bis(4-methacryloyloxypolyethoxyphenyl)propane; and the monomer compound with at least three functional groups comprises at least one selected from the group consisting of trimethylolpropane trimethacrylate, trimethylolethane trimethacrylate, trimethylolpropane trimethacrylate, tetramethylolmethane trimethacrylate, pentaerythritol tetramethylacrylate, bis-trimethylolpropane tetramethacrylate, dipentaerythritol tetramethacrylate, dipentaerythritol hexamethacrylate, and N,N′-(2,2,4-trimethylhexamethylene)bis(2-(aminocarboxyl) propane-1,3-diol) tetramethylacrylate.

7. The method of claim 1 wherein the polymerizable monomer after polymerizing has a refractive index of 1.52 to 1.58, preferably 1.53 to 1.55.

8. The method of claim 1 wherein the inorganic filler comprises an inorganic filler A and an inorganic filler B, wherein the inorganic filler A has an average particle size of 0.1 .Math.m to 10 .Math.m, and the inorganic filler B has an average particle size of 10 nm to 40 nm; the inorganic filler A comprises at least one selected from the group consisting of silica, aluminum silicate, aluminium oxide, titanium dioxide, zirconium oxide, fluorine glass, borosilicate glass, sodium glass, barium glass, barium aluminum silicate glass, strontium or zirconium containing glass, glass ceramic, fluoroaluminosilicate glass, synthetic glass obtained by sol-gel method, fumed silica, calcium fluoride, strontium fluoride, calcium carbonate, kaolin, clay, mica, aluminum sulfate, calcium sulfate, barium sulfate, titanium oxide, calcium phosphate, hydroxyapatite, calcium hydroxide, strontium hydroxide, and zeolite; the inorganic filler B comprises at least one selected from the group consisting of silica, zirconium oxide, titanium oxide, zirconium oxide, zinc oxide, calcium phosphate, and hydroxyapatite; and the inorganic filler A has a refractive index of 1.52 to 1.58, and the inorganic filler B has a refractive index of 1.43 to 1.50.

9. The method of claim 1 wherein the inorganic filler is a surface treated inorganic filler using a surface treatment agent; the surface treatment agent comprises at least one selected from the group consisting of y-methacryloxy propyl trimethoxyl silane, y-methacryloxypropyltriethoxysilane, and y-aminopropyltrimethoxysilane, and preferably y-methacryloxy propyl trimethoxyl silane; the surface treatment agent is used in an amount of 0.1-50 parts by weight, preferably 1-30 parts by weight, based on 100 parts by weight of the inorganic filler; the initiator is at least one selected from the group consisting of dicumyl peroxide, tert-butyl peroxide, benzoyl peroxide, tert-butyl peroxyacetate, and tert-butyl peroxybenzoate; and the colorant is at least one selected from the group consisting of zinc white, titanium dioxide, antimony oxide, vermilion, cadmium red, iron(lll) oxide, chromium oxide, cerium praseodymium yellow, lemon yellow, lead sulfochromate yellow, zinc chrome yellow, iron oxide yellow, bismuth yellow, barium chromate, zirconium vanadium yellow, iron oxide black, carbon black, and graphite.

10. A dental gradient color-resin ceramic restoration material prepared by the method of claim 1 9.

11. The dental gradient color-resin ceramic restoration material of claim 10, wherein in step 1, each of the paste materials is independently prepared by a process comprising: adding a polymerizable monomer, an initiator, an inorganic filler and a colorant into a mixing device, and stirring to be uniform to obtain the paste material; or adding a polymerizable monomer, an initiator, an inorganic filler and a colorant into a mixing device in batches, and stirring to be uniform to obtain the paste material; and the at least two granular materials with different colors obtained in step 1 each independently have a particle size of 0.1 mm to 5 mm.

12. The dental gradient color-resin ceramic restoration material of claim 10, wherein the dispersing in step 1 is conducted at a rotating speed of 20 r/min to 150 r/min, preferably 60 r/min to 120 r/min; the dispersing in step 1 is conducted under a vacuum degree of -0.01 MPa to -0.1 MPa, preferably -0.07 MPa to -0.09 MPa; the tightly combining the at least two layers in step 2 is conducted at a pressure of 0.5 MPa to 5 MPa, preferably 1 MPa to 3 MPa; the polymerizing and curing in step 3 is conducted at a pressure greater than that of the tightly combining the at least two layers in step 2, preferably 2 MPa to 50 MPa, and further preferably 10 MPa to 30 MPa; and the polymerizing and curing in step 3 is conducted at a temperature of 60° C. to 200° C., preferably 100° C. to 150° C.

13. The dental gradient color-resin ceramic restoration material of claim 11, wherein a weight ratio of the polymerizable monomer to the inorganic filler in raw materials for preparing the at least two paste materials with different colors is in a range of 10: 90 to 90: 10, preferably 15: 85 to 40: 60; a weight percentage of the initiator to a total amount of the polymerizable monomer and the inorganic filler is in a range of 0.01 wt% to 10 wt%, preferably 0.1 wt% to 5 wt%; and a weight percentage of the colorant to a total amount of the polymerizable monomer and the inorganic filler is in a range of 0.01 wt% to 3 wt%, preferably 0.1 wt% to 1 wt%.

14. The dental gradient color-resin ceramic restoration material of claim 10, wherein raw materials for preparing the at least two paste materials with different colors further comprise an additive, and the additive is at least one selected from the group consisting of an accelerator, a crosslinking agent, a fluorescent agent, a polymerization inhibitor, an antibacterial agent, an ultraviolet absorber, an anti-tarnishing agent, a viscosity regulator, a wetting agent, an antioxidant, a stabilizer, and a diluent; and a weight percentage of the additive to a total amount of the polymerizable monomer and the inorganic filler is in a range of 0 wt% to 5 wt%, preferably 0.01 wt% to 1 wt%.

15. The dental gradient color-resin ceramic restoration material of claim 10, wherein the polymerizable monomer is a free radical resin monomer, and the free radical resin monomer comprises at least one selected from the group consisting of a monofunctional group-monomer compound, a bifunctional group-monomer compound and a monomer compound with at least three functional groups, wherein the monofunctional group-monomer compound comprises at least one selected from the group consisting of methyl methacrylate, ethyl methacrylate, isobutyl methacrylate, tert-butyl methacrylate, iso-amyl methacrylate, benzyl methacrylate, glycidyl methacrylate, dodecyl methacrylate, tetrahydrofurfuryl methacrylate, 2-(N,N-dimethylamino) ethyl methacrylate, 2,3-dibromopropyl methacrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 6-hydroxyhexyl methacrylate, 10-hydroxydecyl methacrylate, triethylene glycol mono monomethacrylate, propylene glycol monomethacrylate, ethylene glycol methacrylate, diethylene glycol methacrylate, methoxy diethylene glycol methacrylate, polyethylene glycol methacrylate, N-methylol methacrylamide, N-succinyl methyl acrylamide, and 10-methacryloyloxydecyl dihydrogen phosphate; the bifunctional group-monomer compound comprises at least one selected from the group consisting of ethylene glycol dimethacrylate, propylene glycol dimethacrylate, neopentanediol dimethacrylate, butanediol dimethacrylate, hexanediol dimethacrylate, poly(ethylene glycol) dimethacrylate, triethylene glycol dimethacrylate, urethane dimethacrylate, bisphenol A glycerolate dimethacrylate (2,2-bis(4-(3-methacryloyloxy-2-hydroxypropoxy)phenyl)propane), 2,2-bis(4-methacryloyloxyethoxyphenyl)propane, 2,2-bis(4-methacryloyloxydiethoxyphenyl)propane, and 2,2-bis(4-methacryloyloxypolyethoxyphenyl)propane; and the monomer compound with at least three functional groups comprises at least one selected from the group consisting of trimethylolpropane trimethacrylate, trimethylolethane trimethacrylate, trimethylolpropane trimethacrylate, tetramethylolmethane trimethacrylate, pentaerythritol tetramethylacrylate, bis-trimethylolpropane tetramethacrylate, dipentaerythritol tetramethacrylate, dipentaerythritol hexamethacrylate, and N,N′-(2,2,4-trimethylhexamethylene)bis(2-(aminocarboxyl) propane-1,3-diol) tetramethylacrylate.

16. The dental gradient color-resin ceramic restoration material of claim 10, wherein the polymerizable monomer after polymerizing has a refractive index of 1.52 to 1.58, preferably 1.53 to 1.55.

17. The dental gradient color-resin ceramic restoration material of claim 10, wherein the inorganic filler comprises an inorganic filler A and an inorganic filler B, wherein the inorganic filler A has an average particle size of 0.1 .Math.m to 10 .Math.m, and the inorganic filler B has an average particle size of 10 nm to 40 nm; the inorganic filler A comprises at least one selected from the group consisting of silica, aluminum silicate, aluminium oxide, titanium dioxide, zirconium oxide, fluorine glass, borosilicate glass, sodium glass, barium glass, barium aluminum silicate glass, strontium or zirconium containing glass, glass ceramic, fluoroaluminosilicate glass, synthetic glass obtained by sol-gel method, fumed silica, calcium fluoride, strontium fluoride, calcium carbonate, kaolin, clay, mica, aluminum sulfate, calcium sulfate, barium sulfate, titanium oxide, calcium phosphate, hydroxyapatite, calcium hydroxide, strontium hydroxide, and zeolite; the inorganic filler B comprises at least one selected from the group consisting of silica, zirconium oxide, titanium oxide, zirconium oxide, zinc oxide, calcium phosphate, and hydroxyapatite; and the inorganic filler A has a refractive index of 1.52 to 1.58, and the inorganic filler B has a refractive index of 1.43 to 1.50.

18. The dental gradient color-resin ceramic restoration material of claim 10, wherein the inorganic filler is a surface treated inorganic filler using a surface treatment agent; the surface treatment agent comprises at least one selected from the group consisting of y-methacryloxy propyl trimethoxyl silane, y-methacryloxypropyltriethoxysilane, and y-aminopropyltrimethoxysilane, and preferably y-methacryloxy propyl trimethoxyl silane; the surface treatment agent is used in an amount of 0.1-50 parts by weight, preferably 1-30 parts by weight, based on 100 parts by weight of the inorganic filler; the initiator is at least one selected from the group consisting of dicumyl peroxide, tert-butyl peroxide, benzoyl peroxide, tert-butyl peroxyacetate, and tert-butyl peroxybenzoate; and the colorant is at least one selected from the group consisting of zinc white, titanium dioxide, antimony oxide, vermilion, cadmium red, iron(III) oxide, chromium oxide, cerium praseodymium yellow, lemon yellow, lead sulfochromate yellow, zinc chrome yellow, iron oxide yellow, bismuth yellow, barium chromate, zirconium vanadium yellow, iron oxide black, carbon black, and graphite.

Description

DETAILED DESCRIPTION OF THE EMBODIMENTS

[0048] The technical solution of the present disclosure will be further illustrated by the following specific embodiments. It should be understood to those skilled in the art that the described embodiments are only to help understand the present disclosure, and should not be regarded as specific limitation of the present disclosure.

[0049] The following shows compounds used in the examples of the present disclosure and abbreviated symbols thereof. [0050] UDMA: urethane dimethacrylate [0051] Bis—GMA— 2,2-bis(4-(3-methacryloyloxy-2-hydroxypropoxy) phenyl) propane [0052] TEGDMA: triethylene glycol dimethacrylate [0053] BPO: benzoyl peroxide [0054] γ-MPS: γ-methacryloxy propyl trimethoxyl silane

[0055] Inorganic filler: [0056] 1: amorphous barium boroaluminosilicate glass powder GM27884, 0.7 .Math.m (D50); [0057] 2: amorphous barium boroaluminosilicate glass powder GM27884, 0.18 .Math.m (D50); and [0058] 3: fumed silica OX-50, 40 nm (D50).

Example 1

[0059] (1) Amorphous barium boroaluminosilicate glass powder GM27884 with a D50 of 0.7 .Math.m and fumed silica OX-50 with a D50 of 40 nm were modified by using γ-MPS, respectively, to obtain a modified glass powder and a modified fumed silica.

[0060] (2) 70 g of UDMA and 30 g of TEGDMA were added with 1.0 g of BPO as a thermal initiator, to obtain a polymerizable monomer composition.

[0061] (3) According to the formulation in Table 1, the modified filler, the polymerizable monomer composition, colorants and an additive were mixed to be uniform to obtain paste materials with different colors.

[0062] (4) The paste materials with different colors were respectively stirred for 20 min at a rotating speed of 100 r/min under a vacuum degree of -0.09 MPa, to obtain granular materials with an average particle size of 1.2 mm.

[0063] (5) The granular materials were weighted for each layer according to a color transition sequence, then introduced into a press-forming mould in sequence, and spread to be flat. A pressure of 2 MPa was applied to the mould to combine layers tight, to obtain a semi-finished product of a multilayer gradient color-resin ceramic restoration material.

[0064] (6) The semi-finished product of the multilayer gradient color-resin ceramic restoration material obtained in step (5) was pressed at 120° C. and 10 MPa for 2 h for polymerizing and curing, obtaining the multilayer gradient color-resin ceramic restoration material.

TABLE-US-00001 Numb er of layers Modified glass powder Modified fumed silica Polymeriza ble monomer composition Titanium dioxide Iron(III) oxide Lead sulfochro mate yellow Iron oxide black 1 67.41457% 7.49051% 24.96836% 0.02327% 0.03916% 0.04938% 0.01474% 2 67.39639% 7.48849% 24.96163% 0.02822% 0.04750% 0.05989% 0.01788% 3 67.37823% 7.48647% 24.95490% 0.03317% 0.05583% 0.07039% 0.02102% 4 67.36006% 7.48445% 24.94817% 0.03812% 0.06415% 0.08089% 0.02415% 5 67.34191% 7.48243% 24.94145% 0.04306% 0.07247% 0.09138% 0.02728%

Example 2

[0065] (1) Amorphous barium boroaluminosilicate glass powder GM27884 with a D50 of 0.7 .Math.m was modified by using γ-MPS, to obtain a modified glass powder.

[0066] (2) 70 g of UDMA and 30 g of TEGDMA were added with 1.0 g of BPO as a thermal initiator, to obtain a polymerizable monomer composition.

[0067] (3) According to the formulation in Table 2, the modified filler, the polymerizable monomer composition, colorants and an additive were mixed to be uniform to obtain paste materials with different colors.

[0068] (4) The paste materials with different colors were respectively stirred for 20 min at a rotating speed of 80 r/min under a vacuum degree of -0.09 MPa, to obtain granular materials with an average particle size of 5 mm.

[0069] (5) The granular materials were weighted for each layer according to a color transition sequence, then introduced into a press-forming mould in sequence, and spread to be flat. A pressure of 3 MPa was applied to the mould to combine layers tight, to obtain a semi-finished product of a multilayer gradient color-resin ceramic restoration material.

[0070] (6) The semi-finished product of the multilayer gradient color-resin ceramic restoration material obtained in step (5) was pressed at 100° C. and 15 MPa for 4 h for polymerizing and curing, obtaining the multilayer gradient color-resin ceramic restoration material.

TABLE-US-00002 Number of layers Modified glass powder Polymerizable monomer composition Titanium dioxide Iron(III) oxide Iron oxide yellow Iron oxide black 1 79.70147% 19.92537% 0.07610% 0.18463% 0.11217% 0.00026% 2 79.67859% 19.91965% 0.08193% 0.19878% 0.12077% 0.00028% 3 79.61006% 19.90251% 0.09941% 0.24117% 0.14652% 0.00034% 4 79.54164% 19.88541% 0.11685% 0.28348% 0.17223% 0.00040% 5 79.47333% 19.86833% 0.13426% 0.32572% 0.19789% 0.00046%

Example 3

[0071] (1) Amorphous barium boroaluminosilicate glass powder GM27884 with a D50 of 0.18 .Math.m and fumed silica OX-50 with a D50 of 40 nm were modified by using γ-MPS, respectively, to obtain a modified glass powder and a modified fumed silica.

[0072] (2) 70 g of UDMA and 30 g of TEGDMA were added with 1.0 g of BPO as a thermal initiator, to obtain a polymerizable monomer composition.

[0073] (3) According to the formulation in Table 3, the modified filler, the polymerizable monomer composition, colorants and an additive were mixed to be uniform to obtain paste materials with different colors.

[0074] (4) The paste materials with different colors were respectively stirred for 30 min at a rotating speed of 90 r/min under a vacuum degree of -0.08 MPa, to obtain granular materials with an average particle size of 2.1 mm.

[0075] (5) The granular materials were weighted for each layer according to a color transition sequence, then introduced into a press-forming mould in sequence, and spread to be flat. A pressure of 2 MPa was applied to the mould to combine layers tight, to obtain a semi-finished product of a multilayer gradient color-resin ceramic restoration material.

[0076] (6) The semi-finished product of the multilayer gradient color-resin ceramic restoration material obtained in step (5) was pressed at 100° C. and 10 MPa for 4 h for polymerizing and curing, obtaining the multilayer gradient color-resin ceramic restoration material.

TABLE-US-00003 Number of layers Modified glass powder Modified fumed silica Polymerizable monomer composition Titanium dioxide Iron(III) oxide Iron oxide yellow 1 69.82684% 4.98763% 24.93816% 0.00420% 0.14435% 0.09882% 2 69.75932% 4.98281% 24.91404% 0.00584% 0.20063% 0.13735% 3 69.69192% 4.97799% 24.88997% 0.00748% 0.25681% 0.17581% 4 69.62466% 4.97319% 24.86595% 0.00911% 0.31289% 0.21420%

Example 4

[0077] (1) Amorphous barium boroaluminosilicate glass powder GM27884 with a D50 of 0.18 .Math.m was modified by using γ-MPS, to obtain a modified glass powder.

[0078] (2) 65 g of Bis-GMA and 35 g of TEGDMA were added with 1.0 g of BPO as a thermal initiator, to obtain a polymerizable monomer composition.

[0079] (3) According to the formulation in Table 4, the modified filler, the polymerizable monomer composition, colorants and an additive were mixed to be uniform to obtain paste materials with different colors.

[0080] (4) The paste materials with different colors were respectively stirred for 50 min at a rotating speed of 110 r/min under a vacuum degree of -0.08 MPa, to obtain granular materials with an average particle size of 0.1 mm.

[0081] (5) The granular materials were weighted for each layer according to a color transition sequence, then introduced into a press-forming mould in sequence, and spread to be flat. A pressure of 3 MPa was applied to the mould to combine layers tight, to obtain a semi-finished product of a multilayer gradient color-resin ceramic restoration material.

[0082] (6) The semi-finished product of the multilayer gradient color-resin ceramic restoration material obtained in step (5) was pressed at 100° C. and 15 MPa for 4 h for polymerizing and curing, obtaining the multilayer gradient color-resin ceramic restoration material.

TABLE-US-00004 Number of layers Modified glass powder Polymerizable monomer composition Titanium dioxide Iron(III) oxide Iron oxide yellow Iron oxide black 1 79.70147% 19.92537% 0.07610% 0.18463% 0.11217% 0.00026% 2 79.67859% 19.91965% 0.08193% 0.19878% 0.12077% 0.00028% 3 79.61006% 19.90251% 0.09941% 0.24117% 0.14652% 0.00034% 4 79.54164% 19.88541% 0.11685% 0.28348% 0.17223% 0.00040% 5 79.47333% 19.86833% 0.13426% 0.32572% 0.19789% 0.00046%

Comparative Example 1

[0083] (1) Amorphous barium boroaluminosilicate glass powder GM27884 with a D50 of 0.18 .Math.m and fumed silica OX-50 with a D50 of 40 nm were modified by using γ-MPS, respectively, to obtain a modified glass powder and a modified fumed silica.

[0084] (2) 70 g of UDMA and 30 g of TEGDMA were added with 1.0 g of BPO as a thermal initiator, to obtain a polymerizable monomer composition.

[0085] (3) According to the formulation in Table 3, the modified filler, the polymerizable monomer composition, colorants and an additive were mixed to be uniform to obtain paste materials with different colors.

[0086] (4) The paste materials with different colors were introduced into a press-forming mould in sequence, during which after each paste material was introduced to be a layer, a pressure of 2 MPa was applied to the mould for 1 min. The resulting semi-finished product of a multilayer gradient color-resin ceramic restoration material was subjected to polymerizing and curing at 100° C. and 10 MPa for 1 h, obtaining the multilayer gradient color-resin ceramic restoration material.

Comparative Example 2

[0087] (1) Amorphous barium boroaluminosilicate glass powder GM27884 with a D50 of 0.7 .Math.m and fumed silica OX-50 with a D50 of 40 nm were modified by using γ-MPS, respectively, to obtain a modified glass powder and a modified fumed silica.

[0088] (2) 70 g of UDMA and 30 g of TEGDMA were added with 1.0 g of BPO as a thermal initiator, to obtain a polymerizable monomer composition.

[0089] (3) According to the formulation in Table 5, the modified filler, the polymerizable monomer composition, colorants and an additive were mixed to be uniform to obtain paste materials with different colors.

[0090] (4) The paste materials with different colors were simultaneously sprayed into a press-forming mould by using injectors. The resulting semi-finished product of a multilayer gradient color-resin ceramic restoration material was subjected to polymerizing and curing at 120° C. and 8 MPa for 2 h, obtaining the multilayer gradient color-resin ceramic restoration material.

TABLE-US-00005 Num ber of layers Modified glass powder Modified fumed silica Polymeriza ble monomer composition Titanium dioxide Iron(III) oxide Iron oxide yellow Iron oxide black 1 53.52895% 10.70579% 35.68597% 0.00845% 0.03672% 0.03043% 0.00368% 2 53.51087% 10.70217% 35.67391% 0.01204% 0.05236% 0.04339% 0.00525% 3 53.49281% 10.69856% 35.66188% 0.01564% 0.06798% 0.05634% 0.00681%

[0091] Performance of dental curable compositions prepared in Examples and Comparative Examples was tested and evaluated by the following methods.

Particle Size Test

[0092] Method: A high-definition camera was used to capture images of the prepared particles, and the images were stored in a computer. The two-dimensional images were scanned on the computer, and pixel clusters of characteristic points were measured, counted and edited to obtain particle size.

Bending Strength Test

[0093] Method: A composite resin block was cut into test pieces with a size of 1.2*4.0*18 mm, and then surfaces of the test pieces were polished with a 2000 mesh sandpaper by wet grinding. A three-point bending test was carried out with a tensile testing machine under the conditions of a fulcrum spacing of 12 mm and a crosshead speed of 1.0 mm/min, and the average value of ten samples was evaluated.

Fracture Toughness

[0094] Method: A composite resin block was processed into test strips with a size of (4.0 ± 0.2) mm * (3.0 ± 0.2) mm * (44 ± 1) mm. A V-groove with a depth of about (1.0 ± 0.2) mm was made on a surface with a width of 3 mm. A tensile testing machine was used to test the test strips having a V-groove placed downward, under conditions of a span of 40 mm and a crosshead speed of 0.5 mm/min. Fracture load force (N) was recorded and calculated.

Water Absorption Value and Dissolution Value

[0095] Method: A composite resin block was processed into samples with a diameter of (15±1) mm and a thickness of (1.0±0.2) mm, and the diameter and thickness of the samples were measured to calculate the sample volume V. Samples were dried at 37° C. to a constant weight, marked as m.sub.1. Samples with the constant weight were soaked in pure water at 37° C., and taken out and weighed after 7 days, and the resulting weight was marked as m.sub.2. Finally, samples were put into an oven at 37° C. and dried to a constant weight, marked as m.sub.3.

[0096] Water absorption value ρ.sub.ws

[00001]$\rho ws=\left(m_2-m_3\right)/V$

Dissolution value ρ.sub.s1

[00002]${\rho }_{sl}=\left(m_1-m_3\right)/V$

V

[0097] Results of performance test are shown in Table 6.

TABLE-US-00006 Example No. Particl e size Bending strength Elastic modul us Fracture toughness Water absorpti on value Dissoluti on value Color transition mm MPa GPa MPa.Math.m.sup.½ .Math.g/mm.sup.3 .Math.g/mm.sup.3 Example 1 1.2 217 9.1 2.53 26.23 1.27 Natural color transition and good gradient change effect. Example 2 2.5 244 7.2 2.22 25.69 1.31 Natural color transition and good gradient change effect. Example 3 2.1 235 8.2 2.42 28.32 1.31 Natural color transition and good gradient change effect. Example 4 0.7 215 9.5 2.38 26.58 0.87 Natural color transition and good gradient change effect. Compara tive / 190 8.6 1.95 26.75 1.73 Obvious layering. example 1 Compara tive example 2 / 183 7.5 2.08 21.77 1.23 No obvious layering, but poor gradient change effect.

[0098] It can be seen from table 6 that the resin ceramic restoration material prepared according to the present disclosure has natural color transition without obvious layering, and good gradient change effect, and has a bending strength of 215 MPa or more, an elastic modulus of 7.2-9.5 GPa, a fracture toughness of 2.22-2.53 MPa .Math. m.sup.½, a water absorption value of 25.69-28.32 .Math.g/mm.sup.3, and a dissolution value of 0.87-1.31 .Math.g/mm.sup.3.

[0099] The applicant declares that in the present disclosure, a dental gradient color-resin ceramic restoration material and a preparation method thereof are illustrated through the above examples, but the present disclosure is not limited to the above examples, i.e., not meaning that the present disclosure is implemented only by the above examples. It should be clear to those skilled in the art that any improvement of the present disclosure, such as equivalent substitution of raw materials of the product of the present disclosure, addition of auxiliary ingredients, selection of specific means, should fall within the scope of protection and disclosure of the present disclosure.