JP2002255721A - Curable composition for dental use - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a polymerization-curable composition for dental uses, excellent in plugging operability of the uncured paste thereof, having small polymerization shrinkage on curing, and capable of giving a composite restorative material for dental uses excellent in surface lubricity and abrasion resistance. SOLUTION: This curable composition for dental uses comprises (A) an inorganic filler comprising inorganic particles and/or an aggregate thereof each having 0.1-1 μm average particle diameter and treated with a specified silane coupling agent, such as 8-methacryloyloxyoctyl trimethoxysilane, having a (meth) acryloyloxy group bound to a silicon atom through an 8-20C alkylene chain, (B) an organic/inorganic composite filler and (C) a polymerizable monomer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a dental curable composition which can be suitably used as a dental restoration material.

[0002]

2. Description of the Related Art Dental composite restorations have rapidly spread as materials for restoring treated teeth because of their ability to impart a color tone equivalent to that of natural teeth and ease of operation. Most of the treatments are performed not only with composite restoration materials but also for restoration of posterior teeth and the like under high occlusal pressure.

[0003] Dental composite restorative materials are generally mainly composed of a polymerizable monomer (monomer), a filler, and a polymerization catalyst. However, the operability of the paste before curing, and the aesthetic and mechanical properties of the cured product. And the like greatly depend on the type, shape, particle size, filling amount and the like of the filler used.

For example, conventionally, a dental composite restoration material containing a relatively large crushed inorganic filler having a particle size exceeding several μm has been known. However, the dental composite restoration material has a mechanical strength of a hardened body. Although it has high characteristics, it has poor abrasion and abrasion resistance, and has a problem that a glossy finished surface similar to natural teeth cannot be obtained clinically.

In order to solve this problem, it has been proposed to use inorganic particles having an average particle size of 1 μm or less, in particular, inorganic particles having a rounded shape and / or an inorganic filler comprising an aggregate thereof. The surface lubricity has been greatly improved. However, in a dental composite restoration material using such an inorganic filler, the consistency of the paste before curing becomes high because the specific surface area of the filler is extremely large, and the consistency of the paste is determined by the dentist in the oral cavity. In order to adjust to a level that can be used within, the amount of the monomer must be increased, the operability decreases, the shrinkage due to polymerization increases,
Further, there is a problem that the mechanical strength is reduced.

As a method for solving these problems, an organic-inorganic composite filler as disclosed in JP-A-54-107187 and inorganic particles having an average particle diameter of several μm or less and / or an aggregate thereof are disclosed. In general, a method using an inorganic filler such as described above is also known. Here, the organic-inorganic composite filler is obtained by pre-mixing a fine inorganic powder and a polymerizable monomer, polymerizing and curing, and then pulverizing to a particle size of about several tens to several hundreds μm. It is. The above method, by using such an organic-inorganic composite filler, when using the inorganic filler while reducing the operability reduction and polymerization shrinkage compared to when only the inorganic filler as described above is added Achieves excellent surface lubricity and abrasion resistance, which are characteristic features, and increases the viscosity caused by adding an inorganic filler to the paste. Thus, the operability is further suppressed.

[0007]

However, in the above method, inorganic particles having an average particle size of 1 μm or less and / or
Although various physical properties are improved as a whole as compared with the case where the inorganic filler composed of the aggregate is used alone, it cannot be said that a sufficiently satisfactory level of physical properties is necessarily obtained. However, there is a problem that it is difficult to adjust the balance of various physical properties by adding an inorganic filler. For example, when inorganic particles having an average particle size of 1 μm or less and / or an inorganic filler composed of an aggregate thereof are used from the viewpoint of the surface lubricity and abrasion resistance of the cured product, the degree of increase in viscosity is large. If the paste is added until the pastsuki phenomenon disappears, the paste will become sticky or the viscosity will increase to the point where it can not be spread easily. However, there is a problem that a monomer has to be added, and as a result, polymerization shrinkage becomes large. When inorganic particles having a relatively large average particle diameter of about 5 μm and / or a filler made of an aggregate of the inorganic particles are added, the above-mentioned problems are unlikely to occur, but the surface lubricity of the cured product and There is a problem that abrasion resistance is reduced.

[0008] It is also possible to suppress the occurrence of the pasque phenomenon by reducing the particle size of the organic-inorganic composite filler. In this case, however, the paste viscosity increases as described above. It is necessary to add a monomer to the polymer, and polymerization shrinkage becomes large.

As described above, the dental hardening material is a dental composite restoration material having good surface lubricity and abrasion resistance, low polymerization shrinkage during hardening, and good operability during application. The composition was not known. Therefore, an object of the present invention is to provide such a dental polymerization-curable composition.

[0010]

Means for Solving the Problems The present inventors have conducted various studies to solve the above problems. As a result, in the above prior art, the average particle diameter used in combination with the organic-inorganic composite filler is an average particle diameter of several μm or less and / or the surface treated with a specific silane compound as an inorganic filler composed of an aggregate thereof. It has been found that when an inorganic filler composed of 0.1 to 1 μm inorganic particles and / or an aggregate thereof is used, the occurrence of the pastsuki phenomenon can be suppressed while maintaining the viscosity of the paste in a good operability state. Thus, the present invention has been completed.

That is, the present invention relates to (A) an average particle diameter of 0.1 to
Curable dental composition containing 1 μm inorganic particles and / or an inorganic filler composed of an aggregate of the inorganic particles, (B) an organic-inorganic composite filler, and (C) a monomer composition containing a polymerizable monomer. Wherein the inorganic filler of (A) is represented by the following general formula: CH ₂ CC (R ¹ ) —COO— (CH ₂ ) _n —Si—R ² _m R ³ _(3-m) [I] ｛ In the formula, R ¹ is a hydrogen atom or a methyl group, R ² is an alkoxy group having 1 to 6 carbon atoms, an isocyanate group, or a chlorine atom, and R ³ is a hydrocarbon group having 1 to 6 carbon atoms. , M is 2 or 3, and n is an integer of 8-20. A dental curable composition characterized by being an inorganic filler surface-treated with a silane compound represented by｝.

[0012] In the dental curable composition of the present invention, the inorganic filler of (A) has an average particle size of 0.1.
Those having a spherical or substantially spherical shape of the inorganic particles of 1 to 1 μm have a feature that the surface lubricity and abrasion resistance are particularly high. Further, the organic-inorganic composite filler of (B) is:
The average particle size is 0.001 to 1 μm in the polymer matrix
m or spherical or substantially spherical inorganic particles and / or an organic-inorganic composite filler in which agglomerates of the inorganic particles are dispersed have particularly high surface lubricity and abrasion resistance. The composite filler having an average particle size of 1 to 20 μm is characterized in that the filling operability of the curable paste is particularly good.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION The dental curable composition of the present invention comprises:
It comprises an inorganic filler, an organic-inorganic composite filler (hereinafter also simply referred to as a composite filler), and a polymerizable monomer. Here, the composite filler means a composite filler in which inorganic particles are dispersed in a polymer matrix such as a polymer.

The most important feature of the present invention is that a specific inorganic filler surface-treated with the silane compound represented by the above general formula [I] and an organic-inorganic composite filler are used in combination, whereby a cured product is obtained. The surface properties and abrasion resistance of the paste can be improved, the properties of the paste before curing can be made excellent in the filling operation, and the polymerization shrinkage during curing can be reduced.

[0015] The dental curable composition of the present invention,
The inorganic filler (A) surface-treated with the silane compound represented by the general formula [I] has an average particle size of 0.1 to 1
It is necessary that the inorganic filler is composed of inorganic particles of μm and / or an aggregate of the inorganic particles. When the average particle size of the inorganic particles is less than 0.1 μm, the viscosity increases significantly when mixed with an organic-inorganic composite filler and a polymerizable monomer to form a paste, and the surface is treated with the silane compound. However, it is not possible to prepare a paste composition having good operability and sufficiently small polymerization shrinkage. On the other hand, when the average particle size of the inorganic particles exceeds 1 μm, lubricity and abrasion resistance after polymerization and curing are reduced.

In the inorganic filler (A),
Even if it contains an aggregate having a large particle diameter, the aggregate is an aggregate of inorganic particles having an average particle diameter of 0.1 to 1 μm. Lubricity and wear resistance do not decrease. For this reason, it may contain aggregates. The average particle diameter of the inorganic filler (A) is not particularly limited, but is preferably 0.1 to 0.7 μm because the cured product has particularly excellent surface lubricity and wear resistance.
m, particularly preferably from 0.1 to 0.5 μm.

The inorganic filler (A) is not particularly limited as long as it is an inorganic filler composed of inorganic particles having an average particle diameter of 0.1 to 1 μm and / or an aggregate of the inorganic particles. Amorphous silica used in the composition,
Inorganic oxides such as silica zirconia, silica titania, silica barium oxide, quartz, and alumina, and other inorganic compound powders can be used without particular limitation. These inorganic compounds can be used as a composite oxide to which a small amount of an oxide of Group I metal of the periodic table is added for the purpose of easily obtaining a dense one when firing at a high temperature.
As the material of the inorganic filler (A), a cured product having X-ray contrast properties and more excellent abrasion resistance can be obtained.
A composite oxide containing silica and zirconia as main components is particularly preferably used. These inorganic fillers having different particle size distributions and different materials can be used in combination.

The inorganic filler (A) used in the dental curable composition of the present invention has an average particle size of 0.1 to 1 μm.
The shape of the inorganic particles is preferably spherical or substantially spherical in view of the surface lubricity and abrasion resistance of the obtained cured product. The term “substantially spherical” as used herein means that a particle is observed in a unit field of view by taking a photograph of a filler with a scanning electron microscope (SEM), and the particle diameter in a direction perpendicular to its maximum diameter. Divided by its maximum diameter means 0.6 or more.

The method for producing these spherical and substantially spherical inorganic particles is not particularly limited, but it is generally industrially produced by the following method. That is,
A solution containing a hydrolyzable organosilicon compound, or a further hydrolyzable Periodic Table I, II, III, and I
A mixed solution containing a hydrolyzable organic compound containing at least one metal selected from the group consisting of Group V metals, and an alkaline solvent in which these organic compounds are dissolved but the reaction products are not substantially dissolved A so-called sol-gel method, which is obtained by adding the reaction product to the inside and performing hydrolysis to precipitate a reaction product, is suitably employed.

Incidentally, the spherical inorganic filler produced by such a method is generally fired at a temperature of 500 to 1000 ° C. after drying in order to maintain its surface stability. Since particles are aggregated during firing, it is preferable to use a jet mill, a vibrating ball mill, or the like after loosening the aggregated particles and adjusting the particle size. Even if such an operation is performed, it is difficult to completely bring the agglomerated particles into a state before agglomeration, and when the above-described heat treatment is performed, inorganic particles having an average particle size of 0.1 to 1 μm and the A filler mixed with the aggregate is obtained.

The silane compound used for the surface treatment of the inorganic filler (A) is not limited as long as it is represented by the general formula [I]. In addition, the said general formula [I]
R ¹ is a hydrogen atom or a methyl group, R ² is an alkoxy group having 1 to 6 carbon atoms, an isocyanate group, or a chlorine atom, and R ³ is a hydrocarbon group having 1 to 6 carbon atoms, m is 2 or 3, and n is an integer of 8-20. If n is less than 8 even for the same silane compound, the inorganic filler cannot be sufficiently dispersed in the polymerizable monomer, so that the degree of increase in the viscosity of the paste becomes large, and the operability and the polymerization are reduced. It is not preferable from the viewpoint of shrinkage.

The alkoxy group having 1 to 6 carbon atoms for R ² includes a methoxy group, an ethoxy group, an n-propoxy group,
And an iso-propoxy group. In addition, R ³
Examples of the hydrocarbon group having 1 to 6 carbon atoms include an alkyl group having 1 to 6 carbon atoms such as a methyl group, an ethyl group, an n-propyl group, and an iso-propyl group, and a phenyl group.

The above-mentioned general formula [I] which can be suitably used in the present invention.
Specific examples of the silane compound represented by the formula (also simply referred to as silane compound [I]) include the following compounds.

CH ₂ = C (CH ₃ ) -COO- (CH ₂ ) ₈ -Si- (OCH ₃ ) ₃ CH ₂ = C (CH ₃ ) -COO- (CH ₂ ) ₁₀ -Si- (OCH ₃ ) ₃ (hereinafter abbreviated as MDS) CH ₂ = C (CH ₃ ) -COO- (CH ₂ ) ₁₁ -Si- (OCH ₃ ) ₃ (hereinafter abbreviated as MUDS) CH ₂ = CH-COO- (CH ₂ ) ₈ -Si- (OCH ₃ ) ₃ (hereinafter abbreviated as AOS) CH ₂ = CH-COO- (CH ₂ ) ₁₂ -Si- (OCH ₂ CH ₃ ) ₃ CH ₂ = C (CH ₃ )- _{COO- (CH 2) 8 -Si- (} OCH 2 CH 3) 3 CH 2 = C (CH 3) -COO- (CH 2) 12 -Si- (OCH 2 CH 3) 3 ( hereinafter, abbreviated as MDDTES. CH ₂ = C (CH ₃ ) -COO- (CH ₂ ) ₈ -Si-Cl ₃ (hereinafter abbreviated as MOTCS) CH ₂ = C (CH ₃ ) -COO- (CH ₂ ) ₁₀ -Si- ( NCO) ₃ (hereinafter abbreviated as MDTIS) CH ₂ = C (CH ₃ ) -COO- (CH ₂ ) ₁₀ -Si- (CH ₃ ) (OCH ₃ ) ₂ (hereinafter abbreviated as MDMMS) CH ₂ = C (CH ₃ ) —COO— (CH ₂ ) ₁₁ —Si— (C ₆ H ₅ ) (OCH ₃ ) ₂ These silane compounds [I] may be used alone, but may be used by mixing two or more kinds. May be used. In addition, the silane compound [I] can be used in combination with a known surface treating agent other than the silane compound [I] as long as the effects of the present invention are not impaired. Specific examples of other surface treatment agents suitably used include γ-methacryloyloxypropyltrimethoxysilane and hexamethyldisilazane.

Using the silane compound [I], the above (A)
The method for surface-treating the inorganic filler is not particularly limited, and a known method employed when surface-treating a powder using a surface-treating agent such as a silane coupling agent can be used. As a specific example, a method in which the inorganic filler and the silane compound [I] are dispersed and mixed in a suitable solvent using a ball mill or the like, dried by an evaporator or a spray dryer, and then heated to 50 to 150 ° C. And a method of heating the inorganic filler and the silane compound [I] in a solvent such as alcohol while stirring. The amount of the silane compound [I] used at this time is not particularly limited, but from the viewpoint of paste operability and physical properties of the cured product, the inorganic filler (A) 100
It is preferable to use 1 to 30 parts by weight with respect to parts by weight.

The content of the surface-treated inorganic filler (A) in the dental curable composition of the present invention is not particularly limited. However, from the viewpoint of the operability of the paste before curing and the strength of the cured product, the dental curable composition may be used. 20 to 20 wt.
Suitably it is in the range of 60% by weight, especially 30-50% by weight.

The organic-inorganic composite filler (B) used in the dental curable composition of the present invention is not particularly limited, and each has a predetermined amount of inorganic powder (hereinafter, also referred to as a composite filler raw material inorganic filler), and A polymerizable monomer (hereinafter, also referred to as a composite filler raw material monomer) is compounded by a mixer or the like,
After polymerization by heating, light irradiation, etc., pulverize using a vibrating ball mill or jet mill, etc., if necessary,
A sieve, an air classifier, or a composite filler used in a conventional dental curable composition obtained by adjusting to a target particle size distribution by performing a classification step by a water classifier or the like can be used without limitation. .

At this time, as the composite filler raw material inorganic filler, known ones can be used without any limitation.
In order to obtain high surface lubricity and abrasion resistance and high mechanical strength, it is necessary to use inorganic particles having an average particle size of 0.001 to 1 μm and / or an inorganic filler composed of an aggregate of the inorganic particles. Is preferred. As the inorganic filler, the same ones as in the above (A) can be used, and a plurality of types having different particle size distributions and different materials can be used. Also,
The composite filler raw material inorganic filler is also preferably subjected to a hydrophobic treatment by the method as described above on the surface,
In particular, those surface-treated with the silane compound [I] are suitable in terms of mechanical strength, durability and coloring resistance.

As the composite filler raw material monomer, a known polymerizable monomer that can be used as a dental composite restoration material can be used without any limitation. Examples of the composite filler raw material monomer that can be suitably used include a polymerizable monomer having a (meth) acryloyl group, which can form a bond with the silane compound [I]. Examples include the monomers shown in the following A to D.

A Monofunctional vinyl monomers Methacrylates such as methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, hydroxyethyl methacrylate, tetrahydrofurfuryl methacrylate, glycidyl methacrylate, and acrylates corresponding to these methacrylates; or acrylic acid, methacrylic acid, p -Methacryloyloxybenzoic acid, N-2-hydroxy-3-methacryloyloxypropyl-N-phenylglycine, 4-methacryloyloxyethyl trimellitic acid, and anhydrides thereof, 6-methacryloyloxyhexamethylenemalonic acid, 10-methacryloyloxy Decamethylenemalonic acid, 2-methacryloyloxyethyl dihydrogen phosphate, 10-methacryloyloxy Kamechi range hydrogen phosphate, 2-hydroxyethyl hydrogen phenyl phosphonate or the like.

B Bifunctional vinyl monomer B-1 Aromatic compound 2,2-bis (methacryloyloxyphenyl) propane, 2,2-bis [4- (3-methacryloyloxy)
-2-hydroxypropoxyphenyl] propane, 2,
2-bis (4-methacryloyloxyphenyl) propane, 2,2-bis (4-methacryloyloxypolyethoxyphenyl) propane, 2,2-bis (4-methacryloyloxydiethoxyphenyl) propane, 2,2
-Bis (4-methacryloyloxytetraethoxyphenyl) propane, 2,2-bis (4-methacryloyloxypentaethoxyphenyl) propane, 2,2-bis (4-methacryloyloxydipropoxyphenyl) propane, 2 (4-methacryloyl Oxydiethoxyphenyl) -2 (4-methacryloyloxydiethoxyphenyl) propane, 2 (4-methacryloyloxydiethoxyphenyl) -2 (4-methacryloyloxyditriethoxyphenyl) propane, 2 (4-methacryloyloxydipropoxyphenyl) ) -2- (4-Methacryloyloxytriethoxyphenyl) propane, 2,2-
Bis (4-methacryloyloxypropoxyphenyl)
Propane, 2,2-bis (4-methacryloyloxyisopropoxyphenyl) propane and acrylates corresponding to these methacrylates; methacrylates such as 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, and 3-chloro-2-hydroxypropyl methacrylate Alternatively, a vinyl monomer having an -OH group such as an acrylate corresponding to these methacrylates, diisocyanatomethylbenzene,
Diadduct obtained by addition with a diisocyanate compound having an aromatic group such as 4,4'-diphenylmethane diisocyanate;

B-2 Aliphatic Compounds Ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, butylene glycol dimethacrylate,
Neopentyl glycol dimethacrylate, propylene glycol dimethacrylate, 1,3-butanediol dimethacrylate, 1,4-butanediol dimethacrylate, 1,6-hexanediol dimethacrylate and acrylates corresponding to these methacrylates;
A methacrylate such as 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 3-chloro-2-hydroxypropyl methacrylate or a vinyl monomer having an -OH group such as an acrylate corresponding to these methacrylates; hexamethylene diisocyanate; Diadduct obtained by addition with a diisocyanate compound such as methylene diisocyanate, diisocyanate methylcyclohexane, isophorone diisocyanate, and methylene bis (4-cyclohexyl isocyanate); acrylic acid anhydride, methacrylic anhydride, 1,2-bis (3-methacryloyloxy- 2-hydroxypropoxy) ethyl, di (2-methacryloyloxypropyl) phosphate and the like.

C trifunctional vinyl monomers methacrylates such as trimethylolpropane trimethacrylate, trimethylolethanetrimethacrylate, pentaerythritol trimethacrylate, trimethylolmethane trimethacrylate, and acrylates corresponding to these methacrylates.

D tetrafunctional vinyl monomers pentaerythritol tetramethacrylate, pentaerythritol tetraacrylate and diisocyanatemethylbenzene, diisocyanatemethylcyclohexane, isophorone diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, methylene bis (4-cyclohexyl isocyanate), 4, 4-diphenylmethane diisocyanate,
Diadduct obtained from addition of a diisocyanate compound such as tolylene-2,4-diisocyanate and glycidol dimethacrylate.

These polymerizable monomers may be used alone or as a mixture of different types.

The amount ratio of the composite filler raw material inorganic filler and the composite filler raw material monomer in the composite filler raw material composition is not particularly limited, and may be appropriately determined from the viewpoint of the strength and refractive index of the obtained composite filler. 40 to 95% by weight, particularly 60 to 90% by weight of the raw material inorganic filler
Preferably, it is in weight%. Further, in order not to significantly reduce the transparency of the cured body of the dental curable composition, the difference between the refractive index of the composite filler raw material inorganic filler and the refractive index of the composite filler raw material monomer is set to be 0.1 or less. Is preferred.

The composite filler is cured by polymerizing the composite filler raw material monomer as a component thereof using a polymerization initiator. As the polymerization initiator, a known polymerization initiator is used without any particular limitation. Generally, different types of polymerization initiators are used depending on the means of polymerizing the polymerizable monomer. Polymerization means include those based on light energy such as ultraviolet light and visible light, those based on a chemical reaction between a peroxide and an accelerator, and those based on heating, and various polymerization initiators shown below depending on the polymerization means employed. A suitable polymerization initiator may be appropriately selected from the above.

For example, a reaction by light energy (hereinafter, referred to as a reaction)
Examples of the polymerization initiator used for photopolymerization) include benzoin alkyl ethers such as benzoin methyl ether, benzoin ethyl ether, and benzoin isopropyl ether; benzyl ketals such as benzyl dimethyl ketal and benzyl diethyl ketal; benzophenone; Benzophenones such as dimethylbenzophenone and 4-methacryloxybenzophenone; α-diketones such as diacetyl, 2,3-pentadionebenzyl, camphorquinone, 9,10-phenanthraquinone and 9,10-anthraquinone; Thioxanthone compounds such as -diethoxythioxanthone, 2-chlorothioxanthone and methylthioxanthone; bis- (2,6
-Dichlorobenzoyl) phenylphosphine oxide, bis- (2,6-dichlorobenzoyl) -2,5-
Dimethylphenylphosphine oxide, bis- (2,
6-dichlorobenzoyl) -4-propylphenylphosphine oxide, bis- (2,6-dichlorobenzoyl) -1-naphthylphosphine oxide, bis (2
Bisacylphosphine oxides such as (4,6-trimethylbenzoyl) -phenylphosphine oxide can be used.

Incidentally, a reducing agent is often added to the photopolymerization initiator. Examples of such a reducing agent include secondary polymerization agents such as 2- (dimethylamino) ethyl methacrylate, ethyl 4-dimethylaminobenzoate and N-methyldiethanolamine. Examples include aldehydes such as tertiary amines, lauraldehyde, dimethylaminobenzaldehyde, and terephthalaldehyde, and sulfur-containing compounds such as 2-mercaptobenzoxazole, 1-decanethiol, thiosalicylic acid, and thiobenzoic acid.

Examples of the polymerization initiator that can be used for thermal polymerization include benzoyl peroxide, p-chlorobenzoyl peroxide, tert-butylperoxy-2-ethylhexanoate, tert-butylperoxydicarbonate, Peroxides such as diisopropyl peroxydicarbonate, azo compounds such as azobisisobutyronitrile, tributylborane, tributylborane partial oxide, sodium tetraphenylborate, sodium tetrakis (p-fluorophenyl) borate, tetra Boron compounds such as phenylborate triethanolamine salt, 5-butyl barbituric acid, 1-benzyl-5
-Barbituric acids such as phenyl barbituric acid, and sulfinic salts such as sodium benzenesulfinate and sodium p-toluenesulfinate.

These polymerization initiators may be used alone or in combination of two or more. The addition amount of the polymerization initiator may be selected according to the purpose, but is usually 0.01 to 30 parts by weight, more preferably 0.1 to 5 parts by weight, per 100 parts by weight of the polymerizable monomer. Used in parts proportions.

In the polymerization, known additives can be added before the polymerization as long as the effects of the present invention are not impaired. Such additives include pigments, ultraviolet absorbers, and the like. Also, for the purpose of further improving the strength of the cured body, as long as the surface lubricity and wear resistance do not decrease,
Further, an inorganic filler having an average particle diameter of more than 1 μm and / or
Alternatively, an inorganic filler having an average particle size smaller than 0.1 μm may be added. In that case, it is preferable to add the inorganic filler after performing the surface treatment, and it is more preferable to add the inorganic filler after the surface treatment with the silane compound [I].

The cured product obtained by polymerizing the polymerizable composition containing such various components is crushed by the above-mentioned method, and the particle size is adjusted as required to obtain the organic-inorganic (B). It is a composite filler. At this time, the average particle diameter of the organic-inorganic composite filler is not particularly limited, but the curable paste having a low stickiness and a low stickiness and a good filling operability is easily obtained, and the average particle diameter is 1 to 20 μm. And more preferably 5 to 15 μm.

The composite filler may be subjected to washing, decolorization, and surface treatment before being mixed with an inorganic filler, a polymerizable monomer, or the like. Decolorization is generally performed by dispersing the organic-inorganic composite filler in an appropriate solvent, dissolving and stirring the peroxide, and optionally heating, and a known peroxide is preferably used as the peroxide. it can. As the surface treatment method, the above-described procedure for surface treatment of the inorganic filler is similarly applied, and a method in which the surface treatment is performed with the silane compound [I] is more preferable.

The content of the organic-inorganic composite filler (B) in the dental curable composition of the present invention is not particularly limited. However, from the viewpoint of the operability of the paste before curing and the strength of the cured product, the curable composition for dental use is not limited. 30 to 7 based on the weight of the whole object
It is preferably in the range of 0% by weight, especially 40-60% by weight.

The polymerizable monomer (C) used in the dental curable composition of the present invention includes those described above as the composite filler raw material monomer used in producing the organic-inorganic composite filler (B). The same polymerizable monomer can be used. These polymerizable monomers need not particularly be the same as those used in producing the organic-inorganic composite filler (B), and can be used alone or in combination of two or more. .

The content of the polymerizable monomer (C) in the dental curable composition of the present invention is not particularly limited.
From the viewpoint of the filling operability of the curable paste and the strength of the cured body, 5 to 40% by weight, based on the entire dental curable composition,
In particular, it is preferably from 10 to 30% by weight.

The dental curable composition of the present invention is cured by polymerizing the polymerizable monomer as a component thereof using a polymerization initiator. Therefore, the dental curable composition of the present invention preferably contains a polymerization initiator.

As the polymerization initiator used in the dental curable composition of the present invention, the same polymerization initiators as described above as the polymerization initiator which can be used for curing the composite filler (B) are not limited. Can be used without.

In general, in a dental curable composition, photopolymerization is often used as a curing (polymerization) means because of the simplicity of operation at the time of use, and the dental curable composition of the present invention is often used. It is preferable to use a photopolymerization initiator as a polymerization initiator also in the product. Specific examples of particularly preferred photopolymerization initiators among the photopolymerization initiators described above include:
Examples include camphorquinone, bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, and bis (2,6-dimethoxybenzoyl) -2,4,4-trimethylphenylphosphine oxide. These polymerization initiators may be used alone or in combination of two or more. The addition amount of the polymerization initiator may be selected according to the purpose, but is usually 0.01 to 30 parts by weight, more preferably 0.1 to 5 parts by weight, per 100 parts by weight of the polymerizable monomer. Used in parts proportions.

In the dental composition of the present invention, known additives can be blended as long as the effects are not significantly impaired. Examples of such additives include a polymerization inhibitor, a pigment, and an ultraviolet absorber. Further, in the dental curable composition of the present invention, for the purpose of further improving the strength of the cured product, an inorganic filler having an average particle diameter larger than 1 μm as long as the surface lubricity and abrasion resistance are not reduced. In addition, an inorganic filler having an average particle size of less than 0.1 μm may be added. In that case, the surface treatment of the inorganic filler is preferable, and the surface treatment with the silane compound [I] is more preferable.

In general, the curable composition of the present invention is prepared by sufficiently kneading a predetermined amount of each of the above essential components and, if necessary, each of the optional components, and defoaming the paste under reduced pressure to remove air bubbles. Can be obtained by:

The use of the dental curable composition of the present invention is not particularly limited, but specific examples include a composite resin for dental filling. A common method of use is to treat the cavity of the tooth to be restored with an appropriate pretreatment material or adhesive, then directly fill the composite resin for dental filling, form it into a tooth shape, and then use a special light irradiator And a method of polymerizing and curing by irradiating strong light.

[0054]

The present invention will be described below in more detail with reference to examples, but the present invention is not limited to these examples. The surface treatment agents used in the examples and comparative examples,
The polymerizable monomer and the polymerization initiator are as follows.

[Surface treatment agent] As the silane compound [I], 10-methacryloyloxydecyltrimethoxysilane (MDS) 11-methacryloyloxyundecyltrimethoxysilane (MUDS) 8-acryloyloxyoctyltrimethoxysilane (MUDS) AO
S) 12-methacryloyloxydodecyltriethoxysilane (MDDTES) 8-methacryloyloxyoctyltrichlorosilane (MO
TCS) 10-methacryloyloxydecyl triisocyanatosilane (MDTIS) 10-methacryloyloxydecyl monomethyldimethoxysilane (MDMMS) As a surface treatment agent other than silane compound [I], γ-methacryloyloxypropyltrimethoxysilane (hereinafter [Abbreviated as MPS.] [Polymerizable monomer] 2,2-bis [(3-methacryloyloxy-2-hydroxypropyloxy) phenyl] propane (hereinafter abbreviated as bis-GMA) / triethylene glycol dimethacrylate ( Weight ratio 60/40 (hereinafter abbreviated as M-1) [Polymerization initiator] Azobisisobutyronitrile (hereinafter abbreviated as AIBN) Camphorquinone (hereinafter abbreviated as CQ) N, N-dimethyl-p-toluidine (hereinafter abbreviated as DMPT) Further, it is shown in the following Examples and Comparative Examples. , Polymerization shrinkage, surface lubricity of the cured body, and evaluation of the operation of the curable paste according to the following method.

(1) Polymerization shrinkage A SUS split mold having a hole with a diameter of 6 mm and a height of 10 mm was added to a 6 m diameter.
m, 7mm high SUS plunger is inserted and the hole height is 3
mm. This was filled with a curable paste and pressed with a polypropylene film from above. The film was placed face down on a glass table equipped with a dental visible light irradiator, and a short hand that could measure the movement of a minute hand from the SUS plunger was contacted. The curable paste was polymerized and cured by a dental visible light irradiator, and the shrinkage [%] of the cured body 3 minutes after the start of light irradiation was calculated from the vertical movement distance of the short hand.

(2) Surface lubricity A curable paste was filled in a prismatic mold having a width of 2 x 4 and a length of 20 mm, and after being sufficiently cured by photopolymerization, was taken out of the mold. It was immersed in water at 37 ° C. for 24 hours. After polishing the surface of this sample piece with water-resistant abrasive paper No. 1500, Sof-lex
Finish polishing was performed for 1 minute with Superfine (manufactured by 3M), and the glossiness of the surface was visually determined. A sample having excellent lubricity was evaluated as ○, a sample having excellent lubricity was evaluated as ◎, and a sample having poor lubricity was evaluated as ×. (3) Paste operability The properties of the curable paste were evaluated based on the following criteria from the viewpoint of ease of filling operation. That is, when a plastic simulated cavity is filled using a metal filler, there is no operability problem such as stickiness or pastsuki. The balance of pasatsu is good, but there is almost no problem about stickiness that sticks to the filling device during shaping, but there is almost no problem about stickiness, but it is very bad for stickiness that is strong and the paste is easy to cut. Those which strongly adhered to the filling device easily and were very difficult to perform the filling operation were judged as C. Production Example 1 80 g of tetraethyl silicate (manufactured by Nippon Colcoat Chemical Co., Ltd., product name: ethyl silicate 28) was mixed with 400 g of isobutyl alcohol (manufactured by Tozen Petrochemical Co., Ltd.), and 0.0
5 g of a 5% aqueous sulfuric acid solution was added, and the mixture was hydrolyzed with stirring at 40 ° C. for about 1 hour. Then, a solution of 35 g of tetrabutyl zirconate (manufactured by Nippon Soda Co., Ltd.) and a methanol solution of sodium methylate (concentration: 28% by weight) in 200 g of isobutyl alcohol was mixed with stirring, and tetraethyl silicate and tetrabutyl zirconate were mixed. A mixed solution of nate was prepared.

Next, 1000 g of methanol and 250 g of 25% ammonia water were placed in a 3 liter glass container equipped with a stirrer.
Then, 4 g of tetraethyl silicate was added to the ammoniacal alcohol solution into which was introduced, and the mixture was stirred for 30 minutes. Then, the above mixed solution of tetraethyl silicate and tetrabutyl zirconate was added dropwise over about 6 hours. During the reaction, the temperature of the reaction tank was kept at 40 ° C. After completion of the reaction, the solvent was distilled off from the turbid reaction tank liquid using an evaporator, and further dried at 80 ° C. under reduced pressure to obtain a milky white powder.
Further, the milky white powder was fired at 950 ° C. for 1 hour, charged into an alumina pot containing alumina balls having a diameter of 20 mm, and crushed with a ball mill for 5 hours.

[0059] 100 g of the obtained inorganic particles are mixed with 150 g of ethanol.
Then, 3 g of MDS and 1.5 g of water were added, mixed uniformly, and distilled at 80 ° C. for 2 hours. The solvent was distilled off under reduced pressure with an evaporator, and further dried at 80 ° C. under reduced pressure to obtain an inorganic filler F-1. In the same manner, inorganic fillers F-2 to which surface treatment was performed with various surface treatment agents
F-8 was adjusted.

When these silica-zirconia particles were observed with a scanning electron microscope, the average particle diameter of each of the particles was 0.1.
Independent spherical inorganic particles of 2 μm and aggregates of the spherical inorganic particles of 1 to 100 μm were mixed.

The abbreviations of the respective inorganic fillers and the surface treating agents used are shown below. F-1; MDS surface treatment F-2; MUDS surface treatment F-3; AOS surface treatment F-4; MDDTES surface treatment F-5; MOTCS surface treatment F-6; MDTIS surface treatment F- 7; MDMMS surface-treated product F-8; MPS surface-treated product Example 1 In a mortar, AIBN was previously used as a polymerization initiator in a weight ratio of 0.1.
5% of polymerizable monomer M-1 dissolved in inorganic filler F
In -8, 100 parts by weight were added and mixed with 100 parts by weight,
Pasted. This was heated and polymerized at 95 ° C. under a nitrogen atmosphere for 1 hour. This polymer cured product was pulverized using a vibration ball mill, and further subjected to a surface treatment by distilling with 0.02% by weight of γ-methacryloyloxypropyltrimethoxysilane in ethanol at 90 ° C. for 5 hours. The average particle size of the obtained composite filler was 12 μm.

To the polymerizable monomer M-1, 0.5% by weight of a polymerization initiator CQ and 1.5% of DMPT are added and mixed to prepare a uniform polymerizable monomer composition. did. Next, the inorganic filler surface-treated product F-1 and the organic-inorganic composite filler are placed in an agate mortar as a filler, and the polymerizable monomer composition is gradually added thereto. A curable paste was used. Further, the paste was defoamed under reduced pressure to remove air bubbles, and each physical property was evaluated based on the above methods. The composition and results are shown in Table 1.

[0063]

[Table 1]

Examples 2 to 7 The same organic-inorganic composite filler and polymerizable monomer composition as in Example 1 were used except that a surface treating agent different from that in Example 1 was used (A).
The curable paste was prepared using the inorganic fillers F-2 to F-7, and each physical property was evaluated. The results are shown in Table 1.

Example 8 The same inorganic filler and polymerizable monomer composition as in Example 1 were used.
And the physical properties were evaluated.
The results are shown in Table 1.

Examples 9 and 10 The same inorganic filler, organic-inorganic composite filler and polymerizable monomer composition as in Example 1 were used, and the filler composition was (A) inorganic filler F-1: (B) organic-inorganic composite filler 60: 4
A curable paste was prepared by changing the mixture to 0 or 40:60 (all parts by weight), and each physical property was evaluated in the same manner as in Example 1. The results are shown in Table 1.

In all of the compositions of Examples 1 to 10, the polymerization shrinkage before and after curing was small, and the surface lubricity of the cured product was high.
Furthermore, a curable composition having very good operability of the curable paste was achieved.

Comparative Example 1 A curable paste was prepared by removing the inorganic filler from the composition of Example 1, and each physical property was evaluated in the same manner as in Example 1. The results are shown in Table 1.

In Comparative Example 1, the inorganic filler, which is an essential component of the present invention, was not blended, and the operability of the curable paste was extremely large.

Comparative Example 2 A curable paste was prepared by removing the organic-inorganic composite filler from the composition of Example 1, and each physical property was evaluated in the same manner as in Example 1. The results are shown in Table 1.

In Comparative Example 2, the organic-inorganic composite filler which is an essential component of the present invention was not blended, and the polymerization shrinkage was greatly increased as compared with the examples. In addition, the operability of the curable paste also became very sticky.

Comparative Example 3 In the composition of Example 1, the inorganic filler was changed from F-1 to F
The curable paste was adjusted to -8, and each physical property was evaluated in the same manner as in Example 1. The results are shown in Table 1.

In Comparative Example 3, the surface treatment agent of the inorganic filler was changed to MPS not corresponding to the silane compound [I], and the viscosity of the paste was significantly increased. Greatly increased.

Comparative Example 4 In the composition of Example 1, the inorganic filler F-1 was mixed with independent primary particles having an average particle size of 0.04 μm and aggregates of the particles having a particle size of 1 to 100 μm. MD
A curable paste was prepared in place of the S surface-treated product (hereinafter abbreviated as F-9), and each physical property was evaluated in the same manner as in Example 1. The results are shown in Table 1. In addition, the operability of the curable paste also decreased.

The inorganic filler F used in Comparative Example 4
The average particle size of the primary particles of -9 was out of the range of the present invention, and the surface lubricity was good, but the viscosity of the paste was significantly increased, so that the polymerization shrinkage was large as compared with the examples. In addition, the operability of the curable paste also decreased.

Comparative Example 5 In the composition of Example 1, the inorganic filler F-1 was treated with an MDS surface-treated product of ground silica zirconia having an average primary particle diameter of 4.0 μm and each being present as an independent particle ( The curable paste was adjusted in place of F-10), and the physical properties were evaluated in the same manner as in Example 1.
The results are shown in Table 1.

The average particle size of the primary particles of the inorganic filler F-10 used in Comparative Example 5 was out of the range of the present invention, and the inorganic filler used was a single large particle. The sex was greatly inferior.

[0078]

The curable dental composition of the present invention has excellent operability, small polymerization shrinkage during polymerization, and excellent surface lubricity and abrasion resistance.

Claims (4)

[Claims] 1. An inorganic filler comprising (A) an inorganic particle having an average particle diameter of 0.1 to 1 μm and / or an aggregate of the inorganic particle, (B) an organic-inorganic composite filler, and (C) a polymerizable monomer. A curable dental composition comprising a monomer composition comprising: (A) wherein the inorganic filler of (A) is represented by the following general formula: CH ₂ CC (R ¹ ) —COO— (CH ₂ ) _n —Si —R ² _m R ³ _(3-m) [I] {wherein, R ¹ is a hydrogen atom or a methyl group, and R ² is an alkoxy group having 1 to 6 carbon atoms, an isocyanate group, or a chlorine atom. , R ³ is a hydrocarbon group having 1 to 6 carbon atoms, m is 2 or 3, and n is an integer of 8 to 20. A dental curable composition, which is an inorganic filler surface-treated with a silane compound represented by｝. 2. The dental curable composition according to claim 1, wherein the shape of the inorganic particles having an average particle size of 0.1 to 1 μm in the inorganic filler (A) is spherical or substantially spherical. . And (B) an organic-inorganic composite filler in which a spherical or substantially spherical inorganic particle having an average particle diameter of 0.001 to 1 μm and / or an aggregate of the inorganic particle is dispersed in a polymer matrix. The dental curable composition according to claim 1 or 2, which is an inorganic composite filler. 4. An organic-inorganic composite filler (B) having an average particle size of 1 to 20 μm.
A dental composition as described.