JPH1043209A - Dental material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To maintain mechanical strength, discoloration resistance, coloring resistance, and aesthetic appreciation over a long period of time and improve bending elastic modulus and impact strength by impregnating a communicating hole of a porous ceramics with resin. SOLUTION: A porous ceramics is formed from a network-forming oxide such as B2 O3 , P2 O5 , Al2 O3 , ZrO2 , Sb2 O3 including SiO2 and the like, and its communicating hole is impregnated with resin. For example, the ceramics is made by containing a very small amount of MgO, CaO or the like in ceramic using about 67wt. parts SiO2 , about 20wt. parts Al2 O3 , about 6wt. parts K2 O, and about 6wt. parts Na2 O. A binder mixed liquid composed of sublimation hydrocarbon compound is added to powder obtained by grinding the above ceramics, kneaded and burnt. Subsequently, after coupling, resin impregnation and polymerization processing for resin is conducted. The obtained dental material can be improved in physical property such as bending strength or the like and discoloration change resistance.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a dental material. More specifically, the present invention relates to a dental composite material useful as an artificial tooth, an inlay, an onlay, a crown, a crown bridge, and the like.

[0002]

2. Description of the Related Art Generally, dental materials satisfy various requirements such as good mechanical strength and machinability, low cost, excellent aesthetics, no harm to living organisms, and biocompatibility. Is required. Today, resin,
Various materials such as composite materials in which inorganic substances are dispersed in a resin, porcelain, amalgam, and alloys such as precious metals and base metals have been developed and used.

[0003] As dental resins, various resins made of methacrylate-based copolymers, mainly methyl methacrylate, have been developed and used. These are inexpensive, excellent in aesthetics, excellent in discoloration resistance and impact resistance, but low in mechanical strength such as abrasion resistance and bending strength. It is said that the occlusal force at the time of food chewing and the like varies from person to person, but it is on average 78 kg. When this occlusal force is applied to the tip of a tooth, the stress becomes enormous. For this reason, when the resin is used as a dental material, there are drawbacks such as a large amount of wear due to long-term mastication and a frequent deformation of the form due to occlusion.

In order to overcome the disadvantages of the resin,
A composite material (composite resin) in which an inorganic substance is kneaded and dispersed in a methacrylate copolymer resin has been developed. This is because the anterior teeth have good aesthetics required, and the posterior teeth where the mechanical strength is required to be able to withstand occlusion sufficiently is improved compared to the resin alone. Is preferred. In order to improve the physical properties of composite resin, such as mechanical strength and bending strength, and to approach the physical properties similar to natural teeth, it is necessary to uniformly disperse inorganic substances in the resin and increase the filling rate It is. Large particles can increase the filling rate, but when installed in the mouth as artificial teeth, inlays, onlays, crowns, crown bridges, etc., the surface of the composite resin is rough, resulting in a smooth surface , The feeling of discomfort remains in the touch such as tongue. Further, if the inorganic material is lost from the resin surface portion due to use for a long period of time and plaque or the like accumulates in the missing portion, the plaque is colored and the aesthetic property is further reduced. On the other hand, in the case of particles having a small particle size, the total surface area of the inorganic substance in the same volume is larger than that of the particles having a large particle diameter, and the viscosity increases when the inorganic substance is dispersed in the resin. In addition to the limitations, there are difficulties in handling and operability when molding or cutting to form an inlay, onlay, crown, crown bridge, or the like in the manufacture of an artificial tooth or clinically. In addition, when an ultrafine powder is used, it is difficult to obtain uniform dispersibility in the resin because the fine particles are easily aggregated due to a weak charge on the particle surface or Van der Waals force, etc. This also causes difficulties in handling and operability when molding or cutting into artificial inlays, onlays, crowns, crown bridges, etc. in the manufacture of artificial teeth or clinically. And the surface is rough due to aggregation, and a feeling of incongruity is left in touch such as tongue. Attempts have been made to improve the above-mentioned disadvantages by interposing fine particles in the gaps between coarse particles, so-called different combinations of particle diameters such as coarse particles and fine particles as particles to be filled in the resin, Satisfactory dispersion in obtaining a uniform dispersion and a high filling rate have not yet been obtained. For these reasons, a composite resin having satisfactory mechanical strength, discoloration resistance and coloration resistance over the long term has not yet been obtained.

[0005] Porcelain is a ceramic-based dental material that has been used for a long time, has abrasion resistance and bending strength, is excellent in aesthetics, discoloration resistance, coloring resistance, etc., and is harmful to living organisms. Non-irritating, non-irritating in the oral cavity, stable dental material that does not change in material even after long-term use. However, they are more expensive than resins and composite resins, and have a drawback that they are less elastic and brittle, are less susceptible to impact, and are liable to crack or break. Also,
When a porcelain material is manufactured, the shrinkage due to firing is large, and it is difficult to fire accurately to a predetermined shape. Normally, it will be used after polishing and shaping, but thermal cracks at the time of correction polishing will induce micro cracks, and by repeatedly receiving the daily occlusal pressure due to the chewing movement of food and biting hard things, The crack grows and breaks due to fatigue, or when the load at the time of occlusion is excessive, it breaks. Also, when using a porcelain material as a porcelain tooth as a denture, since there is no adhesiveness between the porcelain tooth and the resin serving as the floor or abutment, the porcelain tooth is provided with a mechanical holding means such as a pin or a maintenance hole,
Although the porcelain and resin are integrated, these holding means are susceptible to stress concentration, and if improperly installed, cracks may occur in the resin at the periphery or broken ceramic teeth after being installed in the oral cavity. Or cause it. In addition, it becomes easy for ceramic teeth to fall off from the resin denture base. For this reason, the production of good dentures using ceramic teeth requires skill and is costly.

[0006] In addition, metal materials such as amalgam, noble metals, base metals, and the like, which satisfy various physical properties, are poor in aesthetics due to their metallic luster and tend to be avoided, and are eluted in the oral cavity to reduce toxicity. There are some indications that the adverse effects on the human body are concerned.

When these dental materials are used for dental treatment as artificial teeth, inlays, onlays, crowns, crown bridges, etc., it is necessary to perform processing with an accuracy of at least about 50 to 100 μm using various machines and instruments. become. It takes considerable skill to be able to perform such precision processing by hand, and it is not easy to always maintain such precision. In addition, it is difficult to perform such processing with high efficiency, and this also contributes to high costs. From the input of dental processing data to processing, design, cutting and cutting of dental materials for the purpose of securing skilled personnel, performing processing in a short time with high accuracy, and reducing costs. Attempts have been made to use a CAD / CAM system to perform the finishing process consistently.
There is a need for the development of dental materials more suitable for the / CAM system.

[0008]

SUMMARY OF THE INVENTION In view of the above-mentioned circumstances, the present invention provides a dental material which has solved the above-mentioned disadvantages of conventional dental materials such as resin, composite resin, porcelain, metal material and the like. It was created as a result of intensive research to develop, and can maintain mechanical strength such as abrasion resistance and bending strength, discoloration resistance, coloring resistance, and aesthetics over a long period of time. To provide an inexpensive dental material excellent in impact strength, impact strength, etc. In addition, CAD / CAM
The purpose is to provide dental materials that are also suitable for the system. The purpose of the present invention and other objects, functions and effects will be apparent from the following detailed description and drawings.

[0009]

The above object has been achieved by impregnating a resin into a communicating hole of a porous ceramic. More specifically, a composite material obtained by impregnating a resin with porous ceramics formed and sintered into a shape such as an artificial tooth, an inlay, an onlay, a crown, a crown bridge, or a block shape suitable for CAD / CAM. It was achieved by doing That is,
The dental material of the present invention is characterized in that a porous ceramic is impregnated with a resin. Preferably, the porous ceramic is formed from at least a network-forming oxide, and the porous ceramic is formed from a network-forming oxide, an intermediate oxide, and a network-modified oxide. More preferably, The apparent porosity of the porous ceramic is 0.5
It is preferably about 70%. Preferably, the surface of the porous ceramic is subjected to a coupling treatment. More specifically, for example, the surface of the porous ceramic is subjected to a coupling treatment with at least one coupling agent selected from a silane coupling agent, a titanate coupling agent, and a zircoaluminate coupling agent. Preferably. The resin is preferably one having a polymer of a monomer and / or oligomer containing at least an ethylenic double bond.

[0010]

DETAILED DESCRIPTION OF THE INVENTION The network forming oxide is SiO._Two 
Focusing on B_Two O_Three , P_Two O_Five , Al_Two O_Three, ZrO
_Two , Sb_Two O_Five It is preferable to use such as. And inside
Al oxide as the interoxide_Two O_Three , ZrO_Two , BeO, Ti
O_Two And the like, and CaO, Na_Two O,
K_Two O, MgO, Li_Two O, CsO_Two , BaO, La_Two 
O_Three , Y _Two O_Three , ZnO, etc., are appropriately selected according to the application,
Use in combination. In particular, aluminosilicate-based
K_Two O-Al_Two O_Three -SiO_Two , K_Two O-Na_Two OA
l_Two O_Three -SiO_Two , Borosilicate Na_Two OB_Two O
_Three -SiO_Two , Aluminoborosilicate Na_Two O-Al
_Two O_Three -B_Two O_Three -SiO_Two Is a combination of porous sera
Preferred for making mixes. In the above combination
The component ratio of the component is SiO_Two Aluminokei
Acid salt K_Two O-Al_Two O_Three -SiO_Two In, Si
O_Two 40 to 80% by weight, K_Two 1 to 30% by weight of O, A
l_Two O_Three Is 5 to 30% by weight, and K_Two O-Na_Two OA
l_Two O_Three -SiO_Two In the case of SiO_Two From 40 to 80
% By weight, K_Two O to 1 to 30% by weight, Na_Two O is 1-10
Wt%, Al_Two O_Three To 5 to 30% by weight. Houkei
Acid salt Na_Two OB_Two O_Three -SiO_Two In, Si
O_Two From 60 to 95% by weight of Na_Two O 0.1 to 10 weight
%, B_Two O_Three To 1 to 30% by weight. Alumino Hoke
Itate Na_Two O-Al_Two O_Three -B_Two O_Three -SiO_Two To
In the case of SiO_Two From 60 to 90% by weight of Na_Two O
0.1-15% by weight, Al_Two O_ThreeFrom 1 to 25% by weight, B_Two
 O_Three To 1 to 20% by weight. In addition, it becomes the above ratio
Yes, some feldspars may be used to
Needless to say. In addition, ceramics made of crystals and crystals
May be used. For example,
Heat treatment is applied to the combination of
May be used to produce porous ceramics.
No. The particle size of the fine powder of these materials
In order to obtain an immersible pore distribution, the average particle size is 3.0 to 3.0.
50 μm is preferred. More preferably, the range is 5 to 30 μm.
It is an enclosure. If the average particle size is less than 3.0 μm, the porous ceramic
The porosity of the mix is reduced,
The diameter of the resin becomes fine and the resin becomes difficult to impregnate,
From the point of causing a decrease in elasticity, etc.
Not preferred. However, when the average particle size is less than 3.0 μm,
Even, for example, binder used, molding pressure,
By appropriately selecting the sintering temperature, sintering time, etc.
Form a mix or compound for resin as described below.
If you use low-viscosity materials, you can get the teeth
A slight decrease in the modulus of physical properties of medical materials
Although it may be rubbed, it has excellent surface properties and other properties.
From the above, those having an average particle size of less than 3.0 μm are also regarded as dental materials.
Then it can be used. Average particle size exceeds 50μm
And resin surface impregnation after resin impregnation and abrasion resistance
Not good. In this way, the difference in particle size
Although some differences may occur in physical properties and properties,
Indicates mechanical strength such as abrasion resistance, bending strength, discoloration resistance, and adhesion resistance
Can be selected as appropriate as long as color and aesthetics are not affected
Noh. For example, powder for producing porous ceramics
Even if the average particle size of the particles exceeds 50 μm,
Has a structure that contains a lot of things less than 150 μm
If used, binder used, molding pressure, sintering temperature, sintering time
Porous with almost good communication holes by appropriately selecting etc.
Porous ceramics can be formed. And the many
The through-holes of porous ceramics are used for resin
Surface properties are slightly inferior if polymerized by penetration of compound
Can be said to be superior to those of dental porcelain
Is good, and the resin compound should be of high viscosity.
Is there an advantage such as being able to penetrate
Thus, such a configuration can also be used.

In addition, Fe ₂ O is added to these material fine powders.
_3, a fine powder of CeO _2, or the like MnO ₂ by adding small amount, it is possible to reproduce a color tone similar to natural teeth or Toha. By adding a small amount of fine powder of silica stone or kaolin, the bending strength of the fired ceramic can be increased.
The fine particles of silica will contribute to maintaining the shape during firing, and the fine particles of kaolin will contribute to increasing the plasticity of the raw material powder and facilitating molding.

[0012] From these material fine powders, appropriately selected,
Disperse the binder evenly, use a mold or the like to make artificial teeth,
It is molded into a predetermined shape such as a shape of an inlay, an onlay, a crown, a crown bridge or the like, or a block shape for CAD / CAM. Of course, it is also possible to mold into a predetermined shape using only the material fine powder without using a binder, depending on the material fine powder and / or the molding pressure. Binders include water, clay, phosphate, natural starch, protein, seaweed (alginic acid), sugar, natural rubber, bitumen, natural waste liquid (pulp, sugar-tight), and other thermoplastic resins such as polyethylene, epoxy , A thermosetting resin such as urethane, a synthetic rubber, a sublimable hydrocarbon compound (polycyclic compound), and the like, but are not limited thereto. One or two or more kinds of the above binders are mixed and used depending on the application. In order to uniformly disperse the binder in the material fine powder, it is necessary to use the binder in an appropriate liquid state.However, since the binder having a high liquid viscosity is difficult to disperse, the liquid viscosity of the binder is reduced. It must be lowered, which is done by diluting the binder in a solvent. As the solvent, alcohols, ketones, ethers, and cycloalkanes can be used. The binder mixture of the binder and the solvent volatilizes by firing,
A porous ceramic having a communication hole is formed.

After being formed into a predetermined shape, it is fired to obtain a porous ceramic. The firing temperature and firing time vary depending on the material to be fired, the porosity capable of forming the communication hole, and the like. The apparent porosity of the porous ceramic is preferably 0.5 to 70%. If it is less than 0.5%, the elasticity is lost and the communication hole cannot be formed. If it exceeds 70%, the strength is insufficient and the shape is difficult to maintain, which is not preferable. Apparent porosity is 1
When it is 5 to 55%, the number of communication holes is large and the pore distribution is stable,
It is desirable because the flexural modulus and flexural strength can be balanced. The firing can be carried out in either vacuum firing or atmospheric firing. By firing, the binder is sublimated, evaporated or burned to volatilize and the fine powder is sintered. In order to obtain a porous body, it is also possible to elute the vitreous part by a strong acid treatment after sintering to obtain a porous body. Since it is difficult to form pores and it takes a long time for the strong acid treatment, the above method is preferable but not unsuitable.

Preferably, the surface of the communication hole of the porous ceramic is subjected to a coupling treatment using a silane coupling agent, a titanate coupling agent, or a zircoaluminate coupling agent. Examples of the silane coupling agent include tetramethoxysilane, tetraethoxysilane, methyltrimethoxysilane, ethyltrimethoxysilane, phenyltrimethoxysilane, dimethyltrimethoxysilane, trimethylmethoxysilane, β- (meth) acryloyloxyethyltrimethoxysilane , Γ
-(Meth) acryloyloxypropyltrimethoxysilane, γ-methacryloyloxypropyltriethoxysilane, γ-methacryloyloxypropylmethyldimethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinylmethyldimethoxysilane, p-
Vinylphenyltrimethoxysilane, β- (3,4 epoxycyclohexyl) ethyltrimethoxysilane, γ-
Glycidyloxytrimethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, γ-glycidyloxytriethoxysilane, γ-chlorotrimethoxysilane, γ -Mercaptopropyltrimethoxysilane, methyltrichlorosilane,
Dimethyldichlorosilane or the like can be employed.

Examples of titanate-based coupling agents include isopropyl triisostearoyl titanate, isopropyl tridodecylbenzenesulfonyl titanate, isopropyl tris (dioctyl pyrophosphate) titanate, tetraisopropyl bis (dioctyl phosphite) titanate, and tetraoctyl bis (ditridecyl phosphate). Phyto) titanate, tetra (2,2-diallyloxymethyl-1-butyl) bis (di-tridecyl) phosphite titanate, bis (dioctylpyrophosphate) oxyacetate titanate, bis (dioctylpyrophosphate) ethylene titanate, isopropyltriocta Noyl titanate, isopropyl dimethacryl isostearyl titanate, isopropyl isostearyl dia Riruchitaneto, isopropyl tri (dioctyl phosphate) titanate, isopropyl tricumylphenyl titanate, isopropyl tri (N
-Aminoethyl-aminoethyl) titanate, dicumylphenyloxyacetate titanate, diisostearoylethylene titanate.

As the zircoaluminate-based coupling agent, an alcohol-based cabcomodo or a glycol-based cabcomodo can be employed.

These coupling agents are used alone or in combination of two or more. Although the reaction mechanism of the coupling agent has not yet been fully elucidated,
For example, when a silane coupling agent is used among the coupling agents, the alkoxy group (CH ₃ O) of the silane coupling agent is hydrolyzed by water as a solvent or water absorbed by the solvent, and methanol is removed. It is said that it is eliminated to form a silanol group (SiOH), which undergoes a condensation reaction with a silanol group generated by hydrolysis by water present on the surface of the porous ceramics and bonds thereto. On the other hand, the methacryloyl group is preferable because it improves the adhesiveness to the resin and improves the flexural strength and flexural modulus of the resin-impregnated ceramic. In addition, the coupling agent can improve the impregnation and wettability of the resin, and assist in the infiltration of the resin into the fine pores of the porous ceramics compared to when there is no coupling treatment, shortening the infiltration time and improving It is preferable because it can give a good impregnation. Needless to say, the use of a coupling agent is not necessarily required.

The coupling agent is uniformly dispersed in a solvent to form a solution, and the coupling agent is allowed to penetrate through the pores of the porous ceramic. As a diluting solvent for the silane coupling agent, a solvent that can dissolve silane alkoxyl and water at a lower concentration is preferable, and alcohols and ethers can be used. Silanol groups dissolved in water are unstable,
Since the condensation reaction occurs due to aging, it is necessary to stably store the silane coupling agent and the solvent in the same dispersion state as at the time of mixing the solvent. It is necessary to stably carry out the condensation reaction with the surface of the porous ceramic, and therefore, it is desirable to add an acidic component.
Acid components to be added include acetic acid, phosphoric acid, formic acid, hydrochloric acid,
Sulfuric acid or the like can be used. At that time, the pH was 4.0 to 6.0.
It is preferable that the silane coupling agent be in a weakly acidic range because the silane coupling agent is stable in the solvent. If the time from mixing of the coupling agent to treatment is short, it is not always necessary to adjust the pH of the acidic component. Alcohols and ethers can be used as a diluting solvent for the titanate-based coupling agent and the zircoaluminate-based coupling agent. The amount of the coupling agent is not particularly limited, but is preferably 0.1 to 200 parts by weight based on 100 parts by weight of the porous ceramic.
Parts by weight, more preferably 0.5 to 100 parts by weight. The concentration of the coupling agent in the diluting solvent is not particularly limited, but is preferably lower in viscosity in order to sufficiently penetrate into the pores of the communication holes of the porous ceramic. In order to allow the solution of the coupling agent to efficiently penetrate into the details of the communication holes of the porous ceramic and to cause a condensation reaction between the porous ceramic and the coupling agent, the coupling agent is subjected to ultrasonic waves and / or under reduced pressure. Preferably, the porous ceramic is immersed in the solution. The reaction temperature is preferably from room temperature to about 120 ° C., and the reaction time is usually completed in less than 24 hours, depending on the concentration of the solution.

Resins to be impregnated into porous ceramics include thermoplastic resins such as vinyl acetate, vinyl chloride, vinylidene chloride, (meth) acrylate, vinyl propionate, butylene, propylene, acrylonitrile, and styrene; melamine; phenol. , Epoxy, urethane and other thermosetting resin systems,
A species or a system in which three or more species are mixed can be adopted. Of these, a polymerizable compound containing at least one ethylenic double bond is preferable. This is because they have low viscosity, hardly soften or swell after polymerization, have water resistance, alkali resistance, chemical resistance, short polymerization time, especially after molding into artificial teeth, inlays, onlays, crowns, crown bridges, This is because it is excellent in adhesion to denture bases, abutments and natural teeth via a luting agent. One ethylenic double bond
Examples of the compound containing methyl (meth) acrylate, ethyl (meth) acrylate, isopropyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, n-butyl (meth) acrylate, i-butyl (meth) acrylate, t-butyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate,
Tetrahydrofurfuryl (meth) acrylate, glycidyl (meth) acrylate, 2-methoxyethyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, benzyl (meth) acrylate, trifluoroethyl (meth) acrylate, heptadecafluorodecyl ( (Meth) acrylate, diethylaminoethyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, lauryl (meth) acrylate, tridecyl (meth) acrylate, stearyl (meth) acrylate, alkyl (meth) acrylate, cyclohexyl (meth) acrylate, allyl (Meth) acrylate,
Methoxydiethylene glycol (meth) acrylate,
Methoxy polyethylene glycol (meth) acrylate can be employed.

Compounds containing two ethylenic double bonds include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, and neopentyl glycol di (meth) acrylate. , 1,3-butanediol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 2,2-bis (4-
(Meth) acryloxypolyethoxyphenyl) propane, 2,2-bis (4- (meth) acryloxypolypropoxyphenyl) propane, bis (4- (meth) acryloxypolyethoxyphenyl) methane, 2,2-bis (4- (meth) acryloxydiethoxyphenyl) propane, bis (meth) acryloxyethylhydroxyisocyanurate, methyl 2,6-bis [2 '-(meth) acryloxyethyl] urethanecaproate, 2,2- Bis [p- (2- (meth) acryloxyalkyleneoxy)
Phenyl] propane, 3,9-bis (2- (meth) acryloxy-1,1-dimethylethyl) -2,4,8,1
0-tetraoxaspiro [5,5] undecane and pentaerythritol tetra (meth) acrylate can be employed. It goes without saying that a (meth) acrylate having a urethane bond in the molecule, for example, di-2- (meth) acryloxyethyl-2,2,4-trimethylhexamethylene dicarbamate can also be used. Compounds containing three ethylenic double bonds include trimethylolpropane tri (meth) acrylate, trimethylolethane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, and trimethylolmethane tri (meth) acrylate. Can be adopted. Further, as a compound containing four or more ethylenic double bonds,
1,3,5-tris [1,3-bis ((meth) acryloyloxy) -2-propoxycarbonylaminohexane] -1,3,5- (1H, 3H, 5H) triazine-
2,4,6-trione can be employed.

These resin compounds may be used alone or in combination of two or more in the liquid state of a monomer and / or an oligomer. The combination and mixing ratio of the resin and the artificial tooth, inlay, onlay, crown, It can be determined appropriately according to the use of the crown bridge.

Then, these resin compounds are polymerized using a polymerization catalyst or the like. As the polymerization catalyst or the like, polymerization initiators such as a heat polymerization initiator, a chemical polymerization initiator, and a photopolymerization initiator can be used alone or in combination of two or more. Examples of the heat polymerization initiator include benzoyl peroxide, ketone peroxide, peroxyketal,
Hydroperoxide, dialkyl peroxide,
Peroxides such as diacyl peroxide, peroxyester and peroxycarbonate, 2,2-azobisisobutyronitrile, 2,2-azobis-2-methylbutyronitrile, 2,2-azobis-2-methylhept Nitrile,
1,1-azobis 1-cyclohexanecarbonitrile,
Dimethyl-2,2-azobisisobutyrate, 2,2-
Azobis- (2-aminopropane) dihydride,
2,2-azobis (2-methylbutyronitrile), 4,
4-azobis-4-cyanovaleric acid, 2,2-azobis-
An azo compound such as 2,4-dimethylvaleronitrile can be employed.

As the initiator of the chemical polymerization type, a combination of a peroxide and a tertiary amine or an organic metal compound, a combination of a pyrimidinetriionic acid derivative and a quaternary ammonium chloride, or the like can be used.

As the photopolymerization initiator, a combination of a sensitizer and a reducing agent is generally used. Examples of the sensitizer include camphorquinone, benzyl, diacetyl, benzyldimethylketal, benzyldiethylketal, benzyldi (2-methoxyethyl) ketal, 4,4-dimethylbenzyldimethylketal, anthraquinone, 2-chloroanthraquinone, and 1,2- Benzanthraquinone, 1-
Hydroxyanthraquinone, 1-methylanthraquinone, 2-ethylanthraquinone, 1-bromoanthraquinone, thioxanthone, 2-isopropylthioxanthone, 2-nitrothioxanthone, 2-methylthioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2, , 4-Diisopropylthioxanthone, 2-chloro-7-trifluoromethylthioxanthone, thioxanthone-10,10-dioxide, thioxanthone-10-oxide, benzoin methyl ether, benzoin ethyl ether, isopropyl ether, benzoin isobutyl ether, benzophenone, bis ( 4-dimethylaminophenone) ketone, 4,
4-bisdiethylaminobenzophenone, a compound containing an acid group, or the like can be employed. These compounds may be used alone or in combination of two or more. The compound and the ratio thereof are arbitrarily selected according to the application. Tertiary amines and the like are generally used as the reducing agent. As the tertiary amine, dimethylaminoethyl methacrylate, triethanolamine, methyl 4-dimethylaminobenzoate, ethyl 4-dimethylaminobenzoate, and isoamyl 4-dimethylaminobenzoate are employed. In addition, benzoyl peroxide, organometallic compounds, sulfinic acid derivatives and the like are used. When the photopolymerization initiators are used alone or in combination of two or more, the polymerization reaction can be achieved by irradiation with actinic rays such as ultraviolet rays or visible rays. As a light source,
Various high-pressure, high-pressure, medium-pressure and low-pressure mercury lamps, chemical lamps, carbon arc lamps, metal halide lamps, fluorescent lamps, tungsten lamps, xenon lamps, argon ion lasers and the like can be used.

The amount of the polymerization initiator to be added is appropriately determined in the range of 0.001 to 20% by weight depending on the capacity of the initiator.

The monomer / oligomer containing these polymerization catalysts is allowed to penetrate in a liquid state into the communicating holes of the porous ceramic. The permeation is preferably carried out in ultrasonic waves and / or under reduced pressure. After infiltration, normal temperature, normal pressure, normal temperature
The monomer / oligomer containing the polymerization catalyst is polymerized in a closed vessel under any of the conditions of pressurization, heating / pressurizing, heating / normal pressure, to obtain a resin-impregnated composite material. If necessary, a colorant, a polymerization inhibitor, an oxidation stabilizer, an ultraviolet absorber, a pigment, and a dye can be added to the liquid of the resin compound.

The dental material of the present invention can be manufactured, for example, as follows. Here, the porous ceramics is to be subjected to a silane coupling treatment. As shown in FIG. 1, (a) raw materials such as a ceramic fine powder and a binder whose particle size has been adjusted are mixed (mixing step). Next, (b) molding into a predetermined mold using a mold (molding step). Then, (c) it is taken out of the molding die, vacuum-sintered in a firing furnace, and a binder is volatilized at a predetermined temperature to obtain a porous ceramic having a communication hole (a firing step). (D) The obtained porous ceramic is immersed in a solution in which a silane coupling agent is dispersed, and the silane coupling is carried out in a closed vessel under ultrasonic waves and / or under reduced pressure. The agent is permeated for coupling treatment (coupling treatment step). Then, (e) the coupled porous ceramic is dried (drying step). Next, (f) the coupled porous ceramic is immersed in a mixed solution composed of a monomer and / or an oligomer and a polymerization initiator and the like, and the pressure is reduced in a closed vessel to communicate the coupled porous ceramic. Permeate the mixture into the holes (permeation step). (G) The porous ceramic is taken out of the mixed solution, and the monomer and / or oligomer is polymerized (polymerization step) to obtain a resin-impregnated product.

[0028]

The present invention will be described below in more detail with reference to examples. Of course, the present invention is not limited by the following embodiments.

Example 1 <Preparation of Porous Ceramics Raw Material> SiO ₂ was 67 parts by weight as a network forming oxide, and Al ₂ O ₃ was used as an intermediate oxide.
20 parts by weight, 6 parts by weight of K ₂ O and 6 parts by weight of Na ₂ O as a network modifying oxide were used to form MgO, CaO, Fe ₂ O ₃ , TiO _{2 on} an aluminosilicate ceramic.
_{2. A} ceramic containing a small amount of silica and kaolin is melted to produce a ceramic, which is pulverized by a ball mill to obtain a coarse powder. The coarse powder is sieved, and has an average particle size of 7 μm.
A powder obtained by obtaining a ceramic powder having a particle size of 0.5 to 40 μm is used. 50 parts by weight of a sublimable hydrocarbon compound is used as a binder, and cyclohexane 50 is used as a solvent.
Using a binder mixture consisting of parts by weight, stir 40 parts by weight of the binder mixture with 100 parts by weight of the ceramic powder while adding cyclohexane so that the ceramic powder and the binder mixture are uniformly mixed. -After mixing, the cyclohexane was volatilized at room temperature to obtain a mixed powder. <Sintering of porous ceramics>
/ CAM was molded using a block mold. The molded block is placed in a vacuum firing furnace under a reduced pressure of about 50
The resultant was fired at 0 ° C. for 10 minutes to obtain a porous ceramic block having an apparent porosity of 35%. The apparent porosity is based on a measurement method described later. <Coupling treatment> Porous ceramic block 10
The parts by weight were immersed in an ethanol solvent containing 1 part by weight of γ-methacryloxypropyltrimethoxysilane, and ultrasonic waves were applied for 60 minutes to allow the treatment liquid to penetrate into the communication holes. Next, the porous ceramic block was taken out of the coupling treatment liquid, kept at 100 ° C. for 1 hour, and ethyl alcohol and excess water were evaporated.
Then, a coupling treatment was performed at 120 ° C. for 2 hours to obtain a coupling-treated porous ceramic block. <Resin Penetration and Polymerization> A mixed liquid comprising 39 parts by weight of compound I, 15 parts by weight of compound II, 30 parts by weight of NPG, 16 parts by weight of compound IV, and 0.5 parts by weight of azo catalyst M was prepared. The porous ceramic block having been subjected to the coupling treatment was immersed in the mixed solution, and ultrasonic waves were applied for 6 hours to allow the mixed solution to penetrate into the fine pores of the communication holes. Next, this was polymerized under normal temperature and normal pressure to obtain a resin-impregnated ceramic. Here, compound I is di-2-methacryloxyethyl-2,2,4-trimethylhexamethylenedicarbamate, and compound II is 1,3,5-tris [1,3-bis (methacryloxy) -2- Propoxycarbonylaminohexane] -1,3,5- (1H,
3H, 5H) triazine-2,4,6-trione, NP
G is neopentyl glycol, compound IV is trifluoroethyl methacrylate, azo catalyst M is 2,2-
It means azobis (2-methylbutyronitrile). The obtained resin-impregnated ceramic was subjected to 6.5 × 2.0 × 2
Cut into 4 mm pieces, buffed the surface with titanium oxide, and immersed in water for 1 day to obtain test specimens. Physical properties (flexural strength, flexural modulus, impact strength, abrasion amount) were determined based on the following test method. ), Color tone change (coloring resistance, discoloration resistance). The results are as shown in Table 1.

1) The impregnated state was determined by observing the test piece with the naked eye. If the test piece had no color unevenness, the test piece was evaluated as good. 2) The flexural strength and flexural modulus were measured using an autograph (SH
IMAZU), crosshead speed 1m
It was measured by performing a three-point bending test at m / min and a distance between supporting points of 20 mm. 3) The impact strength was measured using a Dine Stud impact tester (manufactured by Toyo Seiki Seisaku-sho, Ltd.) with an energy of 2.5 kg · cm and using a 6 mm diameter rod copper as the hitting portion. 4) The abrasion resistance was measured by using a wear tester (manufactured by Tokyo Giken Co., Ltd.), and using a hard resin (GC Duradent front teeth) as an abrasion material, and measuring the amount of abrasion after 100,000 times. 5) The test piece was immersed in a basic fuchsine aqueous solution having a concentration of 0.2% at a temperature of 100 ° C. for 60 minutes.
The color difference between the untested specimen and the test specimen was visually determined. The case where the color difference is small is represented by 3, the case where there is a color difference is represented by 2, and the case where the color difference is large is represented by 1. 6) Discoloration resistance was measured using a prototype thermal cycle tester.
The test piece was alternately immersed in cold water at 4 ° C. and warm water at 60 ° C. for 30 seconds, and the color difference between the test piece and the untested sample after 2000 times was visually determined. The case where the color difference is small is represented by 3, the case where there is a color difference is represented by 2, and the case where the color difference is large is represented by 1. In addition,
The measurement of the apparent porosity is based on the following method.
That is, immersing the porous ceramic block in water,
Do this under reduced pressure until no more bubbles are released, 6
The ultrasonic wave is applied for 0 minutes to allow water to penetrate into the micropores.
After the ultrasonic action, the sample is taken out of the water and left for 24 hours, and the weight in the water is measured (weight A). Excess water adhering to the surface is wiped off, and the surface dry weight is measured (weight B). Next, this is dried in a dryer, and the dry weight is measured (weight C). From these weights A, B and C, the apparent porosity was calculated from the following equation. Apparent porosity (%) = (BC) / (BA) × 100

(Examples 2 and 3) In Example 1, the amount of the binder mixture was changed to 30 parts by weight or 25 parts by weight with respect to 100 parts by weight of the ceramic powder. Ceramics were obtained, and the same test as in Example 1 was performed. The obtained results are as shown in Examples 2 and 3 in Table 1.

Example 4 A resin-impregnated ceramic was prepared in the same manner as in Example 1 except that 0.5 parts by weight of benzoyl peroxide (BPO) was used instead of the azo catalyst M. And the same test as in Example 1 was performed. The results obtained are as shown in Example 4 of Table 1.

Example 5 In Example 1, compound I
43 parts by weight, 10 parts by weight of compound II and 35 parts by weight of NPG.
A resin-impregnated ceramic was obtained in the same manner as in Example 1 except that 12 parts by weight of Compound IV and 12 parts by weight of Compound IV were used, and the same test as in Example 1 was performed. The results obtained are as shown in Example 5 of Table 1.

[0034]

[Table 1]

(Example 6) In Example 1, compound I
Was replaced by 43 parts by weight of an aromatic polyfunctional monomer, 2,2-bis [4- (2-hydroxy-3-methacryloxypropoxy) phenyl] propane (compound I)
II) 10 parts by weight, NPG 35 parts by weight, compound IV
Was used in the same manner as in Example 1 except that the resin-impregnated ceramic was obtained, and the same test as in Example 1 was performed. The results obtained are as shown in Example 6 of Table 2.

Example 7 In Example 1, compound I
50 parts by weight, 20 parts by weight of NPG and 10 parts by weight of compound IV.
Parts by weight, instead of compound II, methyl methacrylate (MM
The resin-impregnated ceramic was obtained in the same manner as in Example 1 except that 20 parts by weight of A) was used, and the same test as in Example 1 was performed. The results obtained are as shown in Example 7 of Table 2.

Example 8 A ceramic powder having the composition shown in Example 8 in Table 2 (average particle size 7 μm, particle size 0.5 to 40)
Example 1 using a mixed powder obtained by mixing 100 parts by weight and 40 parts by weight of the same binder mixed solution as in Example 1
And under the reduced pressure of 50 HPa, 110
It was baked at 0 ° C. for 10 minutes to obtain a porous ceramic block having an apparent porosity of 35%. After the coupling treatment was performed in the same manner as in Example 1, the porous ceramic block was immersed in a mixture having the compounding ratio shown in Example 8 in Table 2, and ultrasonic waves were applied for 3 hours. Polymerization was carried out at room temperature and pressure in the same manner as in Example 1 to obtain a resin-impregnated ceramic. The same test as in Example 1 was performed on the obtained resin-impregnated ceramics. The obtained results are as shown in Example 8 of Table 2.

(Example 9) The same mixed powder as in Example 8 was used, and the mixed powder was molded using the same mold as in Example 1.
It was baked at 1100 ° C. for 10 minutes under a reduced pressure of 50 HPa to obtain a porous ceramic block having an apparent porosity of 35%. After the coupling treatment was performed in the same manner as in Example 1, the porous ceramic block subjected to the coupling treatment was immersed in a mixed solution having the compounding ratio shown in Example 9 in Table 2, and ultrasonic waves were applied for 3 hours. Polymerization was carried out at normal temperature and pressure in the same manner as in Example 1 to obtain a resin-impregnated ceramic. The same test as in Example 1 was performed on the obtained resin-impregnated ceramics. The obtained results are as shown in Example 9 of Table 2.

[0039]

[Table 2]

Example 10 As shown in Example 10 of Table 3, 88 parts by weight of feldspar and SiO ₂ as a network forming oxide were used.
A trace amount, Al ₂ O ₃ as an intermediate oxide, 5 parts by weight, and K ₂ O as a network modifying oxide, 10 parts by weight. Na ₂ O, TiO ₂ , Ca
A ceramic containing a small amount of O and MgO is melted to produce a ceramic, which is pulverized by a ball mill to obtain a coarse powder,
The coarse powder is sieved to have an average particle size of 40 μm and a particle size of 1
A ceramic powder of 20 μm or less was obtained. Using a mixed powder obtained by mixing 100 parts by weight of the ceramic powder and 40 parts by weight of the same binder mixture as in Example 1,
And 770 under reduced pressure of 50 HPa.
It was baked at 10 ° C. for 10 minutes to obtain a porous ceramic block having an apparent porosity of 33%. After the coupling treatment was performed in the same manner as in Example 1, the porous ceramic block was immersed in a mixed solution having the compounding ratio shown in Example 9 in Table 2, and ultrasonic waves were applied for 3 hours. Polymerization was carried out at room temperature and pressure in the same manner as in Example 1 to obtain a resin-impregnated ceramic. The same test as in Example 1 was performed on the obtained resin-impregnated ceramics. The obtained results are as shown in Example 10 of Table 3.

Example 11 The ceramics obtained in Example 10 in Table 3 were subjected to a heat treatment at 700 ° C. to precipitate crystals. This was pulverized by a ball mill to obtain a coarse powder, and the coarse powder was sieved to have an average particle size of 40 μm.
Thus, a ceramic powder having a particle size of 120 μm or less was obtained. Using a mixed powder obtained by mixing 100 parts by weight of the ceramic powder and 40 parts by weight of the same binder mixed solution as in Example 1, molded in the same mold as in Example 1, and fired at 770 ° C. for 10 minutes under reduced pressure of 50 HPa. And an apparent porosity of 30
% Of the porous ceramic block was obtained. After the coupling treatment was performed in the same manner as in Example 1, the porous ceramic block was immersed in a mixed solution having the compounding ratio shown in Example 9 in Table 2, and ultrasonic waves were applied for 3 hours. Polymerization was carried out at room temperature and pressure in the same manner as in Example 1 to obtain a resin-impregnated ceramic. The same test as in Example 1 was performed on the obtained resin-impregnated ceramics. The results obtained are as shown in Example 11 of Table 3.

[0042]

[Table 3]

(Comparative Example 1) The same test as in Example 1 was carried out using only the ceramic powder of Example 1 and calcining it at 1300 ° C for 15 minutes to form a molten state without pores. The results obtained are, as shown in Comparative Example 1 of Table 4, large in the flexural modulus, brittle and have no impact strength, and the bending strength is far inferior to that of the examples.

Comparative Example 2 The same test as in Example 1 was performed on the porous ceramic block obtained in Example 1 only by performing a coupling treatment.
The results obtained are shown in Comparative Example 2 in Table 4. Although the porous ceramic block had a flexural modulus, the flexural strength and impact strength were very low, and all were worn in the abrasion resistance test. This is because the bond between the ceramic particles is weak and only a part is bonded. And it is also inferior in coloring resistance and discoloration resistance.

(Comparative Example 3) The porous ceramic block obtained in Example 1 was subjected to a coupling treatment in the same manner as in Example 1, and then impregnated with the same mixture as in Example 1 without using ultrasonic waves. The polymer was polymerized, and the immersion time and polymerization conditions were the same as in Example 1, but the mixture was not sufficiently impregnated and only the surface was impregnated. The same test as in Example 1 was performed on the obtained ceramic composite material. The obtained results are as shown in Comparative Example 3 of Table 4. The obtained ceramic composite material is inferior in bending strength to Example 1.

Comparative Example 4 The same mixed powder as in Example 1 was fired at a firing temperature of 1180 ° C. for 10 minutes under a reduced pressure of 50 HPa to obtain a ceramic block. With respect to the obtained ceramic block, a ceramic composite material was obtained in the same manner as in Example 1 except that the same mixed liquid as in Example 4 was used, and the same test as in Example 1 was performed. The obtained results are as shown in Comparative Example 4 in Table 4. Since the apparent porosity is smaller than that of Example 1, the flexural modulus is large, brittle, and has no impact strength. The bending strength is also inferior to that of Example 1.

[0047]

[Table 4]

[0048]

Since the present invention is configured as described above in detail, it has the following effects. According to the present invention, by impregnating the communication holes of the porous ceramics with the resin, the filling rate of the inorganic material can be increased, so that the mechanical strength such as abrasion resistance and bending strength for a long time, Discoloration resistance, coloring resistance,
Since the aesthetic property can be maintained and the stress in the ceramics is reduced, a dental material excellent in flexural modulus, impact strength, and the like is provided. In addition, CAD / C
A dental material suitable for an AM system can be provided. Further, according to the present invention, the properties such as abrasion resistance, mechanical strength such as bending strength, discoloration resistance, coloring resistance, flexural modulus, impact strength, etc., are the raw materials for ceramics, filling rate, Since various settings can be made by changing the type of resin, etc., it is possible to easily and inexpensively provide the characteristics required by artificial teeth, inlays, onlays, crowns, crown bridges, blocks for CAD / CAM, and the like. be able to.

[Brief description of the drawings]

FIG. 1 is a process chart showing an example of a method for producing a dental material of the present invention.

Claims (7)

[Claims] 1. A dental material comprising a porous ceramic impregnated with a resin. 2. The dental material according to claim 1, wherein the porous ceramic is formed of at least a network-forming oxide. 3. The dental material according to claim 2, wherein the porous ceramic is formed from a combination of a network forming oxide, an intermediate oxide and a network modifying oxide. 4. The dental material according to claim 1, wherein an apparent porosity of the porous ceramic is 0.5 to 70%. 5. The method according to claim 1, wherein the surface of the porous ceramic is subjected to a coupling treatment.
The dental material according to 3 or 4. 6. The surface of a porous ceramic is subjected to a coupling treatment with at least one coupling agent selected from a silane coupling agent, a titanate coupling agent, and a zircoaluminate coupling agent. The dental material according to claim 1, 2, 3, or 4, wherein 7. The resin according to claim 1, wherein the resin has a polymer of a monomer and / or oligomer containing at least an ethylenic double bond.
7. The dental material according to 3, 4, 5 or 6.