WO2021117839A1 - Dental composition - Google Patents

Abstract

The purpose of the present invention is to provide a dental composition that suppresses polymerization shrinkage stress while providing mechanical strength. The present invention pertains to a dental composition comprising a monomer (A), a polymerization initiator (B), polymer particles (C), and a filler (D) (excluding the polymer particles (C)), wherein a light diffusivity D of the dental composition before curing, as calculated by equation [I], is 0.10 or greater.　[I] D = (I₂₀/cos20° + I₇₀/cos70°)/(2I₀) (In this formula, I denotes the intensity of light transmitted through a sample, and I₀, I₂₀ and I₇₀ denote the intensity of light (strength of light) in directions of 0 degrees, 20 degrees, and 70 degrees, respectively, with respect to a direction perpendicular to a sample plate (incident direction of light).)

Description

Dental composition

The present invention relates to a dental composition used in the field of dentistry.

In the treatment of dental caries and associated defects, restoration with a dental bonding material and a dental composite resin has been generally performed. In the case of restoration treatment, the work is usually performed by the following procedure. First, the carious portion is scraped to form a cavity, then a dental bonding material is applied to the cavity, and then the portion to which the dental bonding material is applied is irradiated with visible light to be cured. Next, the dental composite resin is filled on the cured dental bonding material layer, and the finally filled dental composite resin is irradiated with visible light to be cured.

Dental composite resins have become widely used in recent years in place of the conventionally used metal materials because they have aesthetics and excellent operability similar to those of natural teeth. Dental composite resins are generally mainly composed of a polymerizable monomer, a polymerization initiator, and a filler. As a polymerizable monomer, safety in a living body and mechanical strength of a cured product have been used so far. Radical-polymerizable polyfunctional (meth) acrylates are generally used from the viewpoint of abrasion resistance and abrasion resistance. Among them, 2,2-bis [4- (3-methacryloyloxy-2-hydroxypropoxy) phenyl] propane (Bis-GMA) and 2,2,4-trimethylhexamethylenebis (2-carbamoyloxyethyl) dimethacrylate ( UDMA) is widely used. Further, since Bis-GMA, UDMA, and the like have high viscosities by themselves, they are generally diluted with a relatively low-viscosity polymerizable monomer such as triethylene glycol dimethacrylate (3G).

Although dental composite resins have come into widespread clinical use today, improvements are desired in the following points. That is, the operability of the paste of the polymerizable composition used as a dental composite resin, the bending strength of the cured product, the elastic modulus and the abrasion resistance are improved, the water absorption and discoloration are reduced, and the polymerization shrinkage stress at the time of curing is reduced. It has been pointed out that there is still a lot of room for improvement in terms of reduction and aesthetics similar to those of natural teeth.

Particularly in recent years, when the polymerization shrinkage stress is large among these, the dental composite resin is peeled off from the adhesive surface and causes a contraction gap, so it is strongly desired to reduce it as much as possible. The occurrence of contraction gaps causes secondary caries, pulp irritation, coloring, and loss of restorations.

As a technique for reducing such polymerization shrinkage stress, a method of blending a polymer in a dental composition has been proposed. Patent Document 1 discloses a dental composition in which a polymerization shrinkage stress is suppressed by using a dendritic polymer. Further, Patent Document 2 discloses a dental composition in which the polymerization shrinkage stress is suppressed by using a macrocyclic oligomer. Further, Patent Document 3 discloses a particle composite material composed of an organic binder and an inorganic filler, and Patent Document 4 discloses metal fine powder, (meth) acrylic polymer particles, and a polymerizable monomer component. And a dental material comprising a composition containing a polymerization catalyst are disclosed, and Patent Document 5 describes a transparent external filler composed of particles having a maximum diameter of 0.5 mm to 4.0 mm. A dental filling restoration kit comprising a dental polymerizable composition containing a radically polymerizable monomer and a photopolymerization initiator is disclosed.

However, in Patent Document 1, in addition to the suppression of the polymerization shrinkage stress being not enough, since the molecular weight of the dendritic polymer is 20,000 or more, the viscosity of the composition is also high, so that the inorganic filler is filled. The rate could not be increased and the strength was insufficient. Further, in Patent Document 2, in addition to insufficient suppression of polymerization shrinkage stress even by the means, as a phenomenon similar to Patent Document 1, the inclusion of macrocyclic oligomers increases the viscosity, so that the inorganic filler is used. The filling rate cannot be increased and the strength is insufficient. Further, in Patent Document 3, since a large amount of particle composite material having a large particle size is contained, the paste is rough, and further, the particle composite material is treated with a polymerizable functional group, so that it is polymerized at the time of curing. As a result, the effect of reducing the polymerization shrinkage stress was insufficient. In Patent Document 4, since (meth) acrylic polymer particles occupy most of the constituents in the dental material, the mechanical strength was insufficient as in Patent Document 3. Similar to Patent Document 3, Patent Document 5 also contains particles in the paste when a small amount of paste is used clinically because the mechanical strength is insufficient and the particle size is too large. There were cases where it was included and cases where it was not included, and the effect could not be reliably exerted.

Japanese Unexamined Patent Publication No. 2014-24775 Japanese Unexamined Patent Publication No. 2012-188672 JP-A-2002-256010 Japanese Unexamined Patent Publication No. 11-29428 Japanese Unexamined Patent Publication No. 2016-175851

As described above, in the prior art, no dental composition having both suppression of polymerization shrinkage stress and mechanical strength has been found.

Therefore, an object of the present invention is to provide a dental composition that has both suppression of polymerization shrinkage stress and mechanical strength.

As a result of diligent studies, the present inventors have found that a dental composition containing polymer particles and having a light diffusivity D of the dental composition before curing set to a specific value or more can solve the above-mentioned problems. After finding and further studying, the present invention has been completed.

That is, the present invention
[1] The dental composition containing the monomer (A), the polymerization initiator (B), the polymer particles (C), and the filler (D) (excluding the polymer particles (C)) is described below. A dental composition having a light diffusivity D represented by the formula [I] of 0.10 or more;
D = (I ₂₀ / cos 20 ° + I ₇₀ / cos 70 °) / (2I ₀ ) [I]
(In the formula, I represents the luminous intensity of the light transmitted through the sample, and I ₀ , I ₂₀ and I ₇₀ are the luminous intensities in the zero, 20 and 70 degree directions with respect to the direction perpendicular to the sample plate (light incident direction). Light intensity))
[2] The dental composition according to [1], wherein the polymer particles (C) have an average particle size of 0.5 μm to 50 μm;
[3] The dental composition according to [1] or [2], wherein the filler (D) is an inorganic filler;
[4] The dental composition according to any one of [1] to [3], wherein the polymer particles (C) are crosslinked polymer particles;
[5] The dental composition according to any one of [1] to [4], wherein the polymer particles (C) have a refractive index of 1.550 or more;
[6] The dental composition according to any one of [1] to [5], wherein the content of the polymer particles (C) is 0.1 part by mass to 20 parts by mass in 100 parts by mass of the dental composition. ;
[7] Any of [1] to [6], wherein the content of the polymer particles (C) is 0.1 part by mass or more and 50 parts by mass or less with respect to 100 parts by mass of the total amount of the monomer components. The dental composition described;
[8] The dental composition according to any one of [1] to [7], wherein the polymer particles (C) are spherical;
[9] The dental composition according to any one of [1] to [8], wherein the difference in refractive index between the polymer particles (C) and the total monomer mixture before curing is 0.020 or more.
[10] The dental composition according to any one of [1] to [9], wherein the polymer particles (C) consist of (meth) acrylic polymer particles or styrene polymer particles;
[11] The dental composition according to any one of [1] to [10], wherein the monomer (A) contains a monomer (A-1) having an acidic group;
[12] The dental composition according to any one of [1] to [11], wherein the monomer (A) contains a hydrophobic monomer (A-2) having no acidic group;
[13] The dental composition according to any one of [1] to [12], wherein the polymerization initiator (B) contains a water-insoluble photopolymerization initiator (B-2);
[14] The dental composition according to any one of [1] to [13], wherein the filler (D) contains an ultrafine inorganic filler having an average particle size of 1 nm or more and less than 0.1 μm;
[15] The dental composition according to any one of [1] to [13], wherein the filler (D) contains an inorganic filler having an average particle size of more than 1 μm and 10 μm or less.
[16] A dental composite resin comprising the dental composition according to any one of [1] to [15];
[17] A self-adhesive dental composite resin comprising the dental composition according to any one of [1] to [15];
[18] A dental cement comprising the dental composition according to any one of [1] to [15];
Including.

According to the present invention, there are provided a dental composition that suppresses polymerization shrinkage stress and mechanical strength, and a self-adhesive dental composite resin, a dental composite resin, and a dental cement using the composition. .. Further, according to the present invention, a dental composition having light diffusivity and an appropriate curing depth, and a self-adhesive dental composite resin, a dental composite resin, and a dental cement using the composition are provided. Will be done.

It is explanatory drawing about the measuring method of the light diffusivity D of this invention.

The dental composition of the present invention contains the monomer (A), the polymerization initiator (B), the polymer particles (C), and the filler (D) as essential components, and contains the following formula of the dental composition before curing. It is a dental composition having a light diffusivity D represented by [I] of 0.10 or more.
D = (I ₂₀ / cos 20 ° + I ₇₀ / cos 70 °) / (2I ₀ ) [I]
(In the formula, I represents the luminous intensity of the light transmitted through the sample, and I ₀ , I ₂₀ and I ₇₀ are the luminous intensities in the zero, 20 and 70 degree directions with respect to the direction perpendicular to the sample plate (light incident direction). Light intensity))

In the present specification, "(meth) acrylic" is a general term for methacryl and acrylic, and the same applies to expressions similar to this ("(meth) acrylic acid", "(meth) acrylonitrile", etc.). .. In this specification, the upper limit value and the lower limit value of the numerical range (content of each component, value calculated from each component, each physical property, etc.) can be appropriately combined.

The reason why the dental composition of the present invention has both suppression of polymerization shrinkage stress and mechanical strength is not clear, but it is presumed as follows. That is, if the polymer particles (C) are contained and the light diffusivity D before curing is 0.10 or more, it is presumed that the stress generated during the polymerization shrinkage is relaxed. The dental LED light irradiator used for curing the dental composition has a very strong straightness of light and a large curing depth, while stress is accumulated at the interface between the dental composition and the adherend. As a result, the polymerization shrinkage stress applied to the adhesive interface becomes large, which leads to a decrease in adhesiveness and the occurrence of a contraction gap. In the present invention, since the elastic coefficient of the cured product is lowered by containing the polymer particles (C), the polymerization shrinkage stress generated in the dental composition itself is suppressed, and the dental composition is specified. By having the light diffusivity D of, the light irradiated at the time of curing is diffused, concentrated in a specific place and dispersed without applying the polymerization shrinkage stress, so that the polymerization shrinkage stress applied to the bonding interface is further applied. Is presumed to be reduced.

It is essential that the dental composition has a predetermined light diffusivity in the state before curing. Light diffusivity is a property that when light is incident on a translucent material such as a dental composite material, the light is refracted and reflected by the filler inside the material to diffuse the light in various directions. Since the observed reflected diffused light has a color tone that reflects the color tone of the dental composite material and its background color, if the light diffusivity is high, the background color of the restoration and the contour between the restoration and the natural tooth can be obtained. The blurring effect is also large, and therefore it is considered that the color compatibility with natural teeth is improved. As an index of this light diffusivity, a light diffusivity D defined by the following formula [I] has been proposed. FIG. 1 shows an explanatory diagram illustrating the formula [I].
D = (I ₂₀ / cos 20 ° + I ₇₀ / cos 70 °) / (2I ₀ ) [I]
(In the formula, I represents the luminous intensity of the light transmitted through the sample, and I ₀ , I ₂₀ and I ₇₀ are the luminous intensities in the zero, 20 and 70 degree directions with respect to the direction perpendicular to the sample plate (light incident direction). Light intensity))

These luminosity (light intensity) can be measured using a variable angle photometer or a goniometer. The higher the value of the light diffusivity D, the higher the light diffusivity of the cured product. As the variable angle photometer, a variable angle photometer "GP-200" manufactured by Murakami Color Technology Research Institute Co., Ltd. can be used.

According to the dental composition of the present invention, the light diffusivity D of the dental composition before curing is 0.10 or more, preferably 0.12 or more, more preferably 0.15 or more, and 0.20. The above is more preferable, 3.00 or less is preferable, 2.80 or less is more preferable, 2.50 or less is further preferable, and 2.00 or less is most preferable. If the value of the light diffusivity D is smaller than 0.10, the light diffusivity of the dental composition becomes insufficient, and the effect of reducing the polymerization shrinkage stress becomes insufficient. On the other hand, if it is larger than 3.00, the light diffusivity is too strong and sufficient transparency may not be obtained. In the dental composition of the present invention, the light diffusivity D can be set in these preferable ranges by adjusting the difference in refractive index between the monomer component and the polymer particles (C). As a tendency, the smaller the difference in refractive index, the smaller the degree of light diffusivity D, but the degree of light diffusivity D is the type or content of the monomer (A) and the type of polymer particles (C) other than the difference in refractive index. Alternatively, it is also affected by the content, the blending ratio of the monomer (A) and the polymer particles (C), and the like.

Hereinafter, each component used in the dental composition of the present invention will be described.

[Monomer (A)]
Examples of the monomer (A) include a monomer having an acidic group (A-1), a hydrophobic monomer having no acidic group (A-2), and a hydrophilic monomer having no acidic group (A). -3) can be mentioned. As the monomer (A), one type may be blended alone, or two or more types may be used in combination.
-Monomer having an acidic group (A-1)
The monomer (A-1) having an acidic group has an acid etching effect and a primer treatment effect, and is a component that gives a decalcifying action and a penetrating action. In addition, the monomer (A-1) having an acidic group can be polymerized and imparts a curing action. By containing the monomer (A-1) having an acidic group, the adhesiveness to the dentin and the adhesive durability are improved.

The monomer (A-1) having an acidic group has at least one acidic group such as a phosphoric acid group, a pyrophosphate group, a thiophosphate group, a phosphonic acid group, a sulfonic acid group and a carboxylic acid group, and has an acidic group. Examples thereof include a monomer having at least one polymerizable group such as a (meth) acryloyl group, a vinyl group and a styrene group. From the viewpoint of dentin adhesion, a phosphoric acid group-containing monomer is preferable. Specific examples of the monomer (A-1) having an acidic group will be given below.

Examples of the phosphate group-containing monomer include 2- (meth) acryloyloxyethyl dihydrogen phosphate, 3- (meth) acryloyloxypropyl dihydrogen phosphate, 4- (meth) acryloyloxybutyl dihydrogen phosphate, and 5- (meth). ) Acryloyloxypentyl dihydrogen phosphate, 6- (meth) acryloyl oxyhexyl dihydrogen phosphate, 7- (meth) acryloyl oxyheptyl dihydrogen phosphate, 8- (meth) acryloyl oxyoctyl dihydrogen phosphate, 9- (meth) acryloyl Oxynonyldihydrogenphosphate, 10- (meth) acryloyloxydecyldihydrogenphosphate, 11- (meth) acryloyloxyundecyldihydrogenphosphate, 12- (meth) acryloyloxidedecyldihydrogenphosphate, 16- (meth) acryloyloxy Hexadecyldihydrogen phosphate, 20- (meth) acryloyloxyicosildihydrogenphosphate, bis [2- (meth) acryloyloxyethyl] hydrogen phosphate, bis [4- (meth) acryloyloxybutyl] hydrogen phosphate, bis [6- (Meta) acryloyloxyhexyl] hydrogen phosphate, bis [8- (meth) acryloyloxyoctyl] hydrogen phosphate, bis [9- (meth) acryloyloxynonyl] hydrogen phosphate, bis [10- (meth) ) Acryloyloxydecyl] Hydrogenphosphate, 1,3-di (meth) acryloyloxypropyldihydrogenphosphate, 2- (meth) acryloyloxyethylphenylhydrogenphosphate, 2- (meth) acryloyloxyethyl-2-bromoethyl Examples thereof include hydrogen phosphate, bis [2- (meth) acryloyloxy- (1-hydroxymethyl) ethyl] hydrogen phosphate and their acid salts, alkali metal salts, and ammonium salts.

Examples of the pyrophosphate group-containing monomer include bis pyrophosphate [2- (meth) acryloyloxyethyl], bis pyrophosphate [4- (meth) acryloyloxybutyl], and bis pyrophosphate [6- (meth) acryloyloxyhexyl]. ], Bispyrophosphate [8- (meth) acryloyloxyoctyl], bis pyrophosphate [10- (meth) acryloyloxydecyl] and their acid salts, alkali metal salts, and ammonium salts.

Examples of the thiophosphate group-containing monomer include 2- (meth) acryloyloxyethyl dihydrogenthiophosphate, 3- (meth) acryloyloxypropyldihydrogenthiophosphate, 4- (meth) acryloyloxybutyldihydrogenthiophosphate, and 5, -(Meta) Acryloyloxypentyl dihydrogenthiophosphate, 6- (Meta) Acryloyloxyhexyl dihydrogenthiophosphate, 7- (Meta) Acryloyloxyheptyl dihydrogenthiophosphate, 8- (Meta) Acryloyloxyoctyl dihydrogenthiophosphate , 9- (meth) acryloyloxynonyl dihydrogenthiophosphate, 10- (meth) acryloyloxydecyldihydrogenthiophosphate, 11- (meth) acryloyloxyundecyldihydrogenthiophosphate, 12- (meth) acryloyloxide decyldihydro Examples thereof include gentiophosphate, 16- (meth) acryloyloxyhexadecyldihydrogenthiophosphate, 20- (meth) acryloyloxyicosyldihydrogenthiophosphate and their acid salts, alkali metal salts and ammonium salts.

Examples of the phosphonic acid group-containing monomer include 2- (meth) acryloyloxyethylphenylphosphonate, 5- (meth) acryloyloxypentyl-3-phosphonopropionate, and 6- (meth) acryloyloxyhexyl-3-phospho. Nopropionate, 10- (meth) acryloyloxydecyl-3-phosphonopropionate, 6- (meth) acryloyloxyhexyl-3-phosphonoacetate, 10- (meth) acryloyloxydecyl-3-phosphono Examples thereof include acetates and their acid salts, alkali metal salts and ammonium salts.

Examples of the sulfonic acid group-containing monomer include 2- (meth) acrylamide-2-methylpropanesulfonic acid, styrenesulfonic acid, and 2-sulfoethyl (meth) acrylate.

Examples of the carboxylic acid group-containing monomer include a monomer having one carboxy group in the molecule and a monomer having a plurality of carboxy groups in the molecule.

Examples of the monomer having one carboxy group in the molecule include (meth) acrylic acid, N- (meth) acryloyl glycine, N- (meth) acryloyl aspartic acid, O- (meth) acryloyl tyrosine, and N- (meth). ) Acryloyl tyrosine, N- (meth) acryloylphenylalanine, N- (meth) acryloyl-p-aminobenzoic acid, N- (meth) acryloyl-o-aminobenzoic acid, p-vinylbenzoic acid, 2- (meth) acryloyl Oxybenzoic acid, 3- (meth) acryloyloxybenzoic acid, 4- (meth) acryloyloxybenzoic acid, N- (meth) acryloyl-5-aminosalicylic acid, N- (meth) acryloyl-4-aminosalicylic acid, 2- Examples thereof include (meth) acryloyloxyethyl hydrogen succinate, 2- (meth) acryloyloxyethyl hydrogenphthalate, 2- (meth) acryloyloxyethyl hydrogenmalate and acid halides thereof.

Examples of the monomer having a plurality of carboxy groups in the molecule include 6- (meth) acryloyloxyhexane-1,1-dicarboxylic acid and 9- (meth) acryloyloxynonan-1,1-dicarboxylic acid, 10- ( Meta) Acryloyloxydecane-1,1-dicarboxylic acid, 11- (meth) acryloyloxyundecane-1,1-dicarboxylic acid, 12- (meth) acryloyloxidedecane-1,1-dicarboxylic acid, 13- (meth) Acryloyloxytridecane-1,1-dicarboxylic acid, 4- (meth) acryloyloxyethyl trimerite, 4- (meth) acryloyloxyethyl trimerite anhydride, 4- (meth) acryloyloxybutyl trimerite, 4- (Meta) acryloyloxyhexyl trimerite, 4- (meth) acryloyloxydecyl trimerite, 2- (meth) acryloyloxyethyl-3'-(meth) acryloyloxy-2'-(3,4-) Dicarboxybenzoyloxy) propyl succinate and acid anhydrides or acid halides thereof.

Among these monomers having an acidic group (A-1), a phosphoric acid group or a pyrophosphate group-containing (meth) acrylic monomer is preferable because it exhibits better adhesiveness to the dentin. A phosphoric acid group-containing (meth) acrylic monomer is more preferable. Among them, divalent phosphorus having an alkyl group or an alkylene group having 6 to 20 carbon atoms as a main chain in the molecule in that it exhibits high decalcification and high adhesiveness in the absence of an organic solvent. Acid group-containing (meth) acrylic monomers are more preferable, and they contain a divalent phosphate group having an alkylene group having 8 to 12 carbon atoms as a main chain in the molecule such as 10-methacryloyloxydecyldihydrogen phosphate (10-methacryloyloxydecyldihydrogen phosphate). Meta) Acrylic monomers are particularly preferred.

As the monomer (A-1) having an acidic group, one type may be used alone, or two or more types may be used in combination. Adhesiveness may decrease when the content of the monomer (A-1) having an acidic group is too high or too low. Therefore, the content of the monomer (A-1) having an acidic group is preferably in the range of 1 to 50 parts by mass, preferably 3 to 40 parts by mass, based on 100 parts by mass of the total amount of the monomer components in the dental composition. Is more preferable, and the range of 5 to 30 parts by mass is further preferable.

-Hydrophobic monomer having no acidic group (A-2)
The hydrophobic monomer (A-2) having no acidic group (hereinafter referred to as hydrophobic monomer (A-2)) improves the mechanical strength, handleability, and the like of the dental composition. A radical monomer having no acidic group and having a polymerizable group is preferable, and the polymerizable group is more preferably a (meth) acrylic group and / or a (meth) acrylamide group from the viewpoint of easy radical polymerization. The hydrophobic monomer (A-2) means a monomer having no acidic group and having a solubility in water at 25 ° C. of less than 10% by mass, and for example, an aromatic compound-based bifunctionality. Examples thereof include cross-functional monomers such as monomers, aliphatic compound-based bifunctional monomers, and trifunctional or higher-functional monomers.

Examples of the aromatic compound-based bifunctional monomer include 2,2-bis ((meth) acryloyloxyphenyl) propane and 2,2-bis [4- (3- (meth) acryloyloxy-2-). Hydroxypropoxy) phenyl] propane, 2,2-bis (4- (meth) acryloyloxyethoxyphenyl) propane, 2,2-bis (4- (meth) acryloyloxypolyethoxyphenyl) propane, 2,2-bis ( 4- (Meta) acryloyloxydiethoxyphenyl) propane, 2,2-bis (4- (meth) acryloyloxytriethoxyphenyl) propane, 2,2-bis (4- (meth) acryloyloxytetraethoxyphenyl) propane , 2,2-Bis (4- (meth) acryloyloxypentaethoxyphenyl) propane, 2,2-bis (4- (meth) acryloyloxydipropoxyphenyl) propane, 2- (4- (meth) acryloyloxydi) Ethoxyphenyl) -2- (4- (meth) acryloyloxyethoxyphenyl) propane, 2-(4- (meth) acryloyloxydiethoxyphenyl) -2- (4- (meth) acryloyloxytriethoxyphenyl) propane, 2- (4- (meth) acryloyloxydipropoxyphenyl) -2- (4- (meth) acryloyloxytriethoxyphenyl) propane, 2,2-bis (4- (meth) acryloyloxypropoxyphenyl) propane, 2 , 2-Bis (4- (meth) acryloyloxyisopropoxyphenyl) propane and the like. Among these, 2,2-bis [4- (3-methacryloyloxy-2-hydroxypropoxy) phenyl] propane (commonly known as "Bis-GMA"), 2,2-bis (4- (meth) acryloyloxyethoxyphenyl) ) Propane, 2,2-bis (4-methacryloyloxypolyethoxyphenyl) propane (with an average additional molar number of ethoxy groups of 2.6, commonly known as "D-2.6E"), 2,2-bis (4) -(Meta) acryloyloxydiethoxyphenyl) propane, 2,2-bis (4- (meth) acryloyloxytriethoxyphenyl) propane, 2,2-bis (4- (meth) acryloyloxytetraethoxyphenyl) propane, 2,2-Bis (4- (meth) acryloyloxypentaethoxyphenyl) propane is preferred.

Examples of the aliphatic compound-based bifunctional monomer include glycerol di (meth) acrylate, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, and propylene glycol di. (Meta) acrylate, butylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, 1,3-butanediol di (meth) acrylate, 1,5-pentanediol di (meth) acrylate, 1,6- Hexadiol di (meth) acrylate, 1,10-decanediol di (meth) acrylate, 1,2-bis (3-methacryloyloxy-2-hydroxypropoxy) ethane, 2,2,4-trimethylhexamethylenebis (2) -Carbamoyloxyethyl) di (meth) acrylate, N-methacryloyloxyethyl acrylamide, N-methacryloyloxypropylamide and the like can be mentioned. Among these, triethylene glycol diacrylate, triethylene glycol dimethacrylate (commonly known as "3G"), neopentyl glycol di (meth) acrylate, 1,2-bis (3-methacryloyloxy-2-hydroxypropoxy) ethane, 2 , 2,4-trimethylhexamethylene bis (2-carbamoyloxyethyl) dimethacrylate (commonly known as "UDM"), 1,10-decanediol dimethacrylate (commonly known as "DD"), 2,2,4-trimethylhexamethylene bis (2-Carbomoyloxyethyl) dimethacrylate and N-methacryloyloxyethyl acrylamide (commonly known as "MAEA") are preferable.

Examples of the trifunctional or higher monomer include trimethylolpropane tri (meth) acrylate, trimethylolethanetri (meth) acrylate, trimethylolmethane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, and pentaerythritol. Tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, N, N- (2,2,4-trimethylhexamethylene) bis [2- (aminocarboxy) propan-1,3-diol] tetra (meth) Acrylate, 1,7-diacryloyloxy-2,2,6,6-tetra (meth) acryloyloxymethyl-4-oxaheptan and the like can be mentioned. Among these, N, N- (2,2,4-trimethylhexamethylene) bis [2- (aminocarboxy) propane-1,3-diol] tetramethacrylate is preferable.

Among the above-mentioned hydrophobic monomers (A-2), aromatic compound-based bifunctional monomers and aliphatics are easy to adjust the light diffusivity D, mechanical strength, and handleability. Compound-based bifunctional monomers are preferably used. As the aromatic compound-based bifunctional monomer, Bis-GMA and D-2.6E are preferable. Examples of the aliphatic compound-based bifunctional monomer include glycerol di (meth) acrylate, 3G, neopentyl glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, DD, 1,2-. Bis (3-methacryloyloxy-2-hydroxypropoxy) ethane, UDMA, and MAEA are preferred.

Among the above hydrophobic monomers (A-2), Bis-GMA, D- 2.6E, 3G, UDMA, DD and MAEA are more preferable, and D-2.6E, DD and MAEA are even more preferable.

As the hydrophobic monomer (A-2), one type may be blended alone, or two or more types may be used in combination. If the content of the hydrophobic monomer (A-2) is excessive, the permeability of the composition to the dentin may decrease and the adhesive strength may decrease. If the content is too small, the content may decrease. The effect of improving the mechanical strength may not be sufficiently obtained. Therefore, the hydrophobic monomer (A-2) is preferably in the range of 20 to 99 parts by mass, preferably in the range of 40 to 99 parts by mass, based on 100 parts by mass of the total amount of the monomer components in the dental composition. More preferably, the range of 60 to 99 parts by mass is further preferable.

-Hydrophilic monomer having no acidic group (A-3)
The dental composition of the present invention preferably further contains a hydrophilic monomer (A-3) having no acidic group (hereinafter, referred to as a hydrophilic monomer (A-3)). The hydrophilic monomer (A-3) promotes the penetration of the components of the dental composition into the dentin, and also permeates the dentin itself and adheres to the organic component (collagen) in the dentin. As the hydrophilic monomer (A-3), a radical monomer having no acidic group and having a polymerizable group is preferable, and the polymerizable group is a (meth) acrylic group from the viewpoint of easy radical polymerization. And / or (meth) acrylamide groups are more preferred. The hydrophilic monomer (A-3) does not have an acidic group and has a solubility in water at 25 ° C. of 10% by mass or more, and a solubility of 30% by mass or more is preferable. More preferably, it is soluble in water at an arbitrary ratio at 25 ° C. The hydrophilic monomer (A-3) preferably has a hydrophilic group such as a hydroxyl group, an oxymethylene group, an oxyethylene group, an oxyproprene group, or an amide group, and is preferably, for example, 2-hydroxyethyl (meth). Acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 1,3-dihydroxypropyl (meth) acrylate, 2,3-dihydroxypropyl (meth) acrylate, 2-((meth) acryloyloxy ) Hydrophilic monofunctional (meth) acrylate-based monomers such as ethyltrimethylammonium chloride, polyethylene glycol di (meth) acrylate (having 9 or more oxyethylene groups); N-methylol (meth) acrylamide, N-hydroxyethyl (meth) acrylamide, N, N-bis (2-hydroxyethyl) (meth) acrylamide, N-methoxymethyl (meth) acrylamide, N-ethoxymethyl (meth) acrylamide, diacetone (meth) acrylamide, 4 -(Meta) acryloylmorpholine, N-trihydroxymethyl-N-methyl (meth) acrylamide, N, N-dimethylacrylamide and monofunctional (meth) acrylamide-based monomers such as N, N-diethylacrylamide are mentioned. Be done.

Among these hydrophilic monomers (A-3), 2-hydroxyethyl (meth) acrylate, 2,3-dihydroxypropyl (meth) acrylate, diacetone (meth) acrylamide and hydrophilic are used from the viewpoint of adhesion to dentin. A monofunctional (meth) acrylamide-based monomer is preferable, and 2-hydroxyethyl (meth) acrylate, N, N-dimethylacrylamide and N, N-diethylacrylamide are more preferable. As the hydrophilic monomer (A-3), one type may be blended alone, or two or more types may be used in combination.

If the content of the hydrophilic monomer (A-3) in the present invention is too small, the effect of improving the adhesive strength may not be sufficiently obtained, and if it is too large, the mechanical strength may decrease. is there. Therefore, the content of the hydrophilic monomer (A-3) is preferably in the range of 0 to 50 parts by mass and 0 to 40 parts by mass with respect to 100 parts by mass of the total amount of the monomer components in the dental composition. Is more preferable, and the range of 0 to 30 parts by mass is further preferable. The content of the hydrophilic monomer (A-3) may be 0 parts by mass.

[Polymerization initiator (B)]
The polymerization initiator (B) is roughly classified into a photopolymerization initiator and a chemical polymerization initiator, and the photopolymerization initiators are a water-soluble photopolymerization initiator (B-1) and a water-insoluble photopolymerization initiator (B-2). )are categorized. As the polymerization initiator (B), only the water-soluble photopolymerization initiator (B-1) may be used, or only the water-insoluble photopolymerization initiator (B-2) may be used, and the water-soluble photopolymerization may be used. The initiator (B-1) and the water-insoluble photopolymerization initiator (B-2) may be used in combination.

-Water-soluble photopolymerization initiator (B-1)
The water-soluble photopolymerization initiator (B-1) has improved polymerization curability at the hydrophilic tooth surface interface and can realize high adhesive strength. The water-soluble photopolymerization initiator (B-1) has a solubility of 10 g / L or more, preferably 15 g / L or more, more preferably 20 g / L or more, and more preferably 25 g / L or more. Is even more preferable. When the solubility is less than 10 g / L, the water-soluble photopolymerization initiator (B-1) is not sufficiently dissolved in water in the dentin at the adhesive interface, and the polymerization promoting effect is less likely to be exhibited.

Examples of the water-soluble photopolymerization initiator (B-1) include water-soluble acylphosphine oxides, water-soluble thioxanthones, and 1- [4- (2-hydroxyethoxy) -phenyl] -2-hydroxy-2-methyl. (Poly) ethylene glycol chain introduced into the hydroxyl group of -1-propane-1-one, (poly) ethylene glycol chain introduced into the hydroxyl group and / or phenyl group of 1-hydroxycyclohexylphenylketone, 1-hydroxy _{-OCH 2} COO ^- Na ⁺ introduced into the phenyl group of cyclohexylphenyl ketone, 2-hydroxy-2-methyl-1-phenylpropan-1-one hydroxyl group and / or (poly) ethylene glycol chain to the phenyl group Α-Hydroxyalkylacetophenones such as those introduced, those introduced with _{-OCH 2} COO ^- Na ⁺ into the phenyl group of 2-hydroxy-2-methyl-1-phenylpropan-1-one; 2-methyl-1 [ 4- (Methylthio) Phenyl] -2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) Butanone-1 and other α-aminoalkylphenones have four amino groups. Examples include those obtained by chlorinating grade ammonium.

Examples of the water-soluble thioxanthones include 2-hydroxy-3- (9-oxo-9H-thioxanthene-4-yloxy) -N, N, N-trimethyl-1-propaneaminium chloride, 2-hydroxy-. 3- (1-Methyl-9-oxo-9H-thioxanthene-4-yloxy) -N, N, N-trimethyl-1-propaneaminium chloride, 2-hydroxy-3- (9-oxo-9H-thio) Xanthene-2-yloxy) -N, N, N-trimethyl-1-propaneaminium chloride, 2-hydroxy-3- (3,4-dimethyl-9-oxo-9H-thioxanthene-2-yloxy) -N , N, N-trimethyl-1-propaneaminium chloride, 2-hydroxy-3- (3,4-dimethyl-9H-thioxanthene-2-yloxy) -N, N, N-trimethyl-1-propaneaminium Chloride, 2-hydroxy-3- (1,3,4-trimethyl-9-oxo-9H-thioxanthene-2-yloxy) -N, N, N-trimethyl-1-propaneaminium chloride and the like can be used.

Examples of the water-soluble acylphosphine oxides include acylphosphine oxides represented by the following general formula (1) or (2).

In formulas (1) and (2), R ¹ , R ² , R ³ , R ⁴ , R ⁵ , and R ⁶ are independent of each other and are linear or branched alkyl groups having 1 to 4 carbon atoms. Alternatively, it is a halogen atom, and in the formula (1), M is a hydrogen ion, an alkali metal ion, an alkaline earth metal ion, a magnesium ion, a pyridinium ion (the pyridine ring may have a substituent), or HN ^+. R ⁸ R ⁹ R ¹⁰ (in the formula, R ⁸ , R ⁹ and R ¹⁰ are independent of each other, an organic group or a hydrogen atom), and n is 1 or 2. In formula (2), X is a linear or branched alkylene group having 1 to 4 carbon atoms, and R ⁷ is represented by −CH (CH ₃ ) COO (C ₂ H ₄ O) _p CH _3. , P represent an integer from 1 to 1000.

The alkyl groups of R ¹ , R ² , R ³ , R ⁴ , R ⁵ , and R ⁶ are not particularly limited as long as they are linear or branched chains having 1 to 4 carbon atoms, and the methyl group, Ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, 2-methylpropyl group, tert-butyl group and the like can be mentioned. As ^{the alkyl group of R 1} , R ² , R ³ , R ⁴ , R ⁵ , and R ^6, a linear alkyl group having 1 to 3 carbon atoms is preferable, a methyl group or an ethyl group is more preferable, and a methyl group is preferable. Is even more preferable. Examples of the alkylene group of X include a methylene group, an ethylene group, an n-propylene group, an isopropylene group, an n-butylene group and the like. As the alkylene group of X, a linear alkylene group having 1 to 3 carbon atoms is preferable, a methylene group or an ethylene group is more preferable, and a methylene group is further preferable.

When M is a pyridinium ion, the substituent of the pyridine ring includes a halogen atom (fluorine atom, chlorine atom, bromine atom, iodine atom), a carboxy group, and a linear or branched acyl having 2 to 6 carbon atoms. Examples thereof include a group, a linear or branched alkyl group having 1 to 6 carbon atoms, and a linear or branched alkoxy group having 1 to 6 carbon atoms. As M, alkali metal ion, alkaline earth metal ion, magnesium ion, pyridinium ion (the pyridine ring may have a substituent), or HN ⁺ R ⁸ R ⁹ R ¹⁰ (in the formula, the symbol is the above). Ammonium ion (having the same meaning as) is preferable. Examples of the alkali metal ion include lithium ion, sodium ion, potassium ion, rubidium ion, and cesium ion. Examples of the alkaline earth metal ion include calcium ion, strontium ion, barium ion, and radium ion. Examples of the organic group of R ⁸ , R ⁹ , and R ¹⁰ include the same group as the substituent of the pyridine ring (excluding the halogen atom).

Among these, in the formulas (1) and (2), the ^{compounds in which R 1} , R ² , R ³ , R ⁴ , R ⁵ , and R ⁶ are all methyl groups are the storage stability and color tone in the composition. Especially preferable from the viewpoint of stability. On the other hand, examples of ^{M n + include Li +} , Na ⁺ , K ⁺ , Ca ²⁺ , Mg ²⁺ , and ammonium ions derived from various amines, and examples of amines include ammonia, trimethylamine, diethylamine, and dimethyl. Aniline, ethylenediamine, triethanolamine, N, N-dimethylaminomethacrylate, N, N-dimethylaminobenzoic acid and its alkyl ester, N, N-diethylaminobenzoic acid and its alkyl ester, N, N-bis (2-hydroxy) Ethyl) -p-toluidine and the like can be mentioned. As R ⁷ , from the viewpoint of adhesiveness, p is preferably 1 or more, more preferably 2 or more, further preferably 3 or more, particularly preferably 4 or more, preferably 1000 or less, more preferably 100 or less, and 75 or less. More preferably, 50 or less is particularly preferable.

Among these water-soluble acylphosphine oxides, represented by the general formula (1), compounds of general formula (1) M is Li, and the portion corresponding to the group represented by R ⁷ is a molecular weight of 950 A compound represented by the general formula (2) synthesized from polyethylene glycol methyl ether methacrylate is particularly preferable. ^{In these compounds, R 1} , R ² , and R ³ in the general formula (1) ^{and R 1} , R ² , R ³ , R ⁴ , R ⁵ , and R ⁶ in the general formula (2) are as described above. Is.

Water-soluble acylphosphine oxides having such a structure can be synthesized according to a known method, and some of them are also available as commercial products. For example, Chem. Commun. , 2018, 54 (8), 920-923 and the like, and can be synthesized by the method disclosed in JP-A-57-197289 and International Publication No. 2014/095724. One type of water-soluble photopolymerization initiator (B-1) may be used alone, or two or more types may be used in combination.

If the water-soluble photopolymerization initiator (B-1) can be dissolved in water on the surface of the dentin (wet body) and selectively enhance the polymerization curability inside the adhesive interface and the resin impregnated layer, the dental composition It may be dissolved in a substance or dispersed in the composition as a powder.

When the water-soluble photopolymerization initiator (B-1) is dispersed as a powder, if the average particle size is too large, it tends to settle, so 500 μm or less is preferable, 100 μm or less is more preferable, and 50 μm or less is further preferable. On the other hand, if the average particle size is too small, the specific surface area of the powder becomes excessive and the amount dispersible in the composition decreases, so 0.01 μm or more is preferable. That is, the average particle size of the water-soluble photopolymerization initiator (B-1) is preferably in the range of 0.01 to 500 μm, more preferably in the range of 0.01 to 100 μm, and even more preferably in the range of 0.01 to 50 μm.

The average particle size of the powder of each water-soluble photopolymerization initiator (B-1) is an image analysis type particle size distribution measurement software (Mac-View; manufactured by Mountech Co., Ltd.) based on electron micrographs of 100 or more particles. It can be calculated as the volume average particle size after performing image analysis using.

The shape of the initiator when the water-soluble photopolymerization initiator (B-1) is dispersed in powder includes various shapes such as spherical, needle-shaped, plate-shaped, and crushed, but is not particularly limited. The water-soluble photopolymerization initiator (B-1) can be produced by a conventionally known method such as a pulverization method, a freeze-drying method, or a reprecipitation method, and the freeze-drying method is used from the viewpoint of the average particle size of the obtained powder. And the reprecipitation method is preferable, and the freeze-drying method (method 1) is more preferable.

The content of the water-soluble photopolymerization initiator (B-1) is 0 with respect to 100 parts by mass of the total amount of the monomer components in the dental composition from the viewpoint of curability of the obtained dental composition and the like. 0.01 to 20 parts by mass is preferable, 0.05 to 10 parts by mass is more preferable, and 0.1 to 5 parts by mass is further preferable, from the viewpoint of high initial adhesive force and adhesive durability and reduction of polymerization shrinkage stress. When the content of the water-soluble photopolymerization initiator (B-1) is less than 0.01 parts by mass, the polymerization at the bonding interface does not proceed sufficiently, which may lead to a decrease in the bonding strength. On the other hand, when the content of the water-soluble photopolymerization initiator (B-1) exceeds 20 parts by mass, or when the polymerization performance of the water-soluble photopolymerization initiator (B-1) is low, sufficient adhesive strength is obtained. It may not be obtained and may be insufficiently dissolved, dispersed and diffused in the dental composition.

-Water-insoluble photopolymerization initiator (B-2)
From the viewpoint of curability, the dental composition of the present invention has a solubility in water at 25 ° C. of less than 10 g / L in addition to the water-soluble photopolymerization initiator (B-1) (water-insoluble photopolymerization initiator). B-2) (hereinafter referred to as a water-insoluble photopolymerization initiator (B-2)) may be contained. As the water-insoluble photopolymerization initiator (B-2) used in the present invention, a known photopolymerization initiator can be used. The water-insoluble photopolymerization initiator (B-2) may be blended alone or in combination of two or more.

Examples of the water-insoluble photopolymerization initiator (B-2) include (bis) acylphosphine oxides, thioxanthones, ketals, α-diketones, and coumarins other than the water-soluble photopolymerization initiator (B-1). Examples thereof include anthraquinones, benzoin alkyl ether compounds, and α-aminoketone compounds.

Among the (bis) acylphosphine oxides, examples of the acylphosphine oxides include 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2,6-dimethoxybenzoyldiphenylphosphine oxide, and 2,6-dichlorobenzoyldiphenylphosphine oxide. 2,4,6-trimethylbenzoylmethoxyphenylphosphine oxide, 2,4,6-trimethylbenzoylethoxyphenylphosphine oxide, 2,3,5,6-tetramethylbenzoyldiphenylphosphine oxide, benzoyldi (2,6-dimethylphenyl) Phosphate and the like can be mentioned. Examples of bisacylphosphine oxides include bis (2,6-dichlorobenzoyl) phenylphosphine oxide, bis (2,6-dichlorobenzoyl) -2,5-dimethylphenylphosphine oxide, and bis (2,6-dichlorobenzoyl)-. 4-propylphenylphosphine oxide, bis (2,6-dichlorobenzoyl) -1-naphthylphosphine oxide, bis (2,6-dimethoxybenzoyl) phenylphosphine oxide, bis (2,6-dimethoxybenzoyl) -2,4 4-trimethylpentylphosphine oxide, bis (2,6-dimethoxybenzoyl) -2,5-dimethylphenylphosphine oxide, bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide, bis (2,5,6-trimethyl) Benzoyl) -2,4,4-trimethylpentylphosphine oxide and the like can be mentioned.

Examples of the thioxanthones include thioxanthone and 2-chlorothioxanthene-9-one.

Examples of the ketals include benzyldimethyl ketal and benzyldiethyl ketal.

Examples of the α-diketones include diacetyl, benzyl, dl-camphorquinone, 2,3-pentadione, 2,3-octadione, 9,10-phenanthrenequinone, 4,4'-oxybenzyl, acenaphthenquinone and the like. Can be mentioned. Among these, dl-camphorquinone is particularly preferable from the viewpoint of having a maximum absorption wavelength in the visible light region.

Examples of the coumarin compound include 3,3'-carbonylbis (7-diethylamino kumarin), 3- (4-methoxybenzoyl) coumarin, 3-thienoyl coumarin, 3-benzoyl-5,7-dimethoxy kumarin, 3 -Benzoyl-7-methoxykumarin, 3-benzoyl-6-methoxykumarin, 3-benzoyl-8-methoxykumarin, 3-benzoyl kumarin, 7-methoxy-3- (p-nitrobenzoyl) kumarin, 3- (p-) Nitrobenzoyl) coumarin, 3,5-carbonylbis (7-methoxycumarin), 3-benzoyl-6-bromokumarin, 3,3'-carbonylbiscoumarin, 3-benzoyl-7-dimethylaminocumarin, 3-benzoylbenzo [F] Kumarin, 3-carboxykumarin, 3-carboxy-7-methoxykumarin, 3-ethoxycarbonyl-6-methoxykumarin, 3-ethoxycarbonyl-8-methoxykumarin, 3-acetylbenzo [f] kumarin, 3- Benzoyl-6-nitrocoumarin, 3-benzoyl-7-diethylaminocoumarin, 7-dimethylamino-3- (4-methoxybenzoyl) coumarin, 7-diethylamino-3- (4-methoxybenzoyl) coumarin, 7-diethylamino-3 -(4-Diethylamino) coumarin, 7-methoxy-3- (4-methoxybenzoyl) coumarin, 3- (4-nitrobenzoyl) benzo [f] coumarin, 3- (4-ethoxycinnamoyle) -7-methoxycoumarin , 3- (4-Dimethylaminocinnamoyle) coumarin, 3- (4-diphenylaminocinnamoyle) coumarin, 3-[(3-dimethylbenzothiazole-2-iriden) acetyl] coumarin, 3-[(1-methylnaphthoyl) [1,2-d] thiazole-2-iriden) acetyl] coumarin, 3,3'-carbonylbis (6-methoxycumarin), 3,3'-carbonylbis (7-acetoxycmarin), 3,3'- Carbonylbis (7-dimethylaminocoumarin), 3- (2-benzothiazolyl) -7- (diethylamino) coumarin, 3- (2-benzothiazolyl) -7- (dibutylamino) coumarin, 3- (2-benzoimidazolyl) -7 -(Diethylamino) coumarin, 3- (2-benzothiazolyl) -7- (dioctylamino) coumarin, 3-acetyl-7- (dimethylamino) coumarin, 3,3'-carbonylbis (7-dibutylaminocoumarin), 3 , 3'-carbonyl-7-diethylaminocoumarin-7'-bis (butoxyethyl) aminocoumarin, 10- [3- [4- (dimethylamino) phenyl] -1-oxo-2-propenyl] -2,3 6,7-Tetrahydro-1,1,7,7-Tetramethyl-1H, 5H, 11H- [1] benzopyrano [6,7,8-ij] quinolidine-11-one, 10- (2-benzothiazolyl)- 2,3,6,7-tetrahydro-1,1,7,7-tetramethyl-1H, 5H, 11H- [1] benzopyrano [6,7,8-ij] quinolidine-11-one, etc. Examples thereof include compounds described in Japanese Patent Application Laid-Open No. -3109 and Japanese Patent Application Laid-Open No. 10-245525.

Among the above-mentioned coumarin compounds, 3,3'-carbonylbis (7-diethylaminocoumarin) and 3,3'-carbonylbis (7-dibutylaminocoumarin) are particularly preferable.

Examples of the anthraquinones include anthraquinone, 1-chloroanthraquinone, 2-chloroanthraquinone, 1-bromoanthraquinone, 1,2-benz anthraquinone, 1-methylanthraquinone, 2-ethylanthraquinone, 1-hydroxyanthraquinone and the like. ..

Examples of the benzoin alkyl ether compound include benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether and the like.

Examples of the α-aminoketone compound include 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropane-1-one.

Among these water-insoluble photopolymerization initiators (B-2), it is preferable to use at least one selected from the group consisting of (bis) acylphosphine oxides, α-diketones, and coumarin compounds. As a result, a dental composition having excellent photocurability in the visible and near-ultraviolet regions and exhibiting sufficient photocurability using any light source such as a halogen lamp, a light emitting diode (LED), or a xenon lamp can be obtained.

The content of the water-insoluble photopolymerization initiator (B-2) is not particularly limited, but the content of the water-insoluble photopolymerization initiator (B-2) is determined from the viewpoint of curability of the obtained composition. , 0.01 to 10 parts by mass is preferable, 0.05 to 7 parts by mass is more preferable, and 0.1 to 5 parts by mass is preferable with respect to 100 parts by mass of the total amount of the monomer components in the dental composition. The range of parts is more preferred. If the content of the water-insoluble photopolymerization initiator (B-2) exceeds 10 parts by mass, sufficient adhesive strength may not be obtained if the polymerization performance of the polymerization initiator itself is low. In addition, it may cause precipitation from the dental composition.

The mass ratio [(B-1) :( B-2)] of the water-soluble photopolymerization initiator (B-1) and the water-insoluble photopolymerization initiator (B-2) in the present invention is preferably 10: 1. It is ~ 1:10, more preferably 7: 1 to 1: 7, still more preferably 5: 1 to 1: 5, and most preferably 3: 1 to 1: 3. If a water-soluble photopolymerization initiator (B-1) is blended in a mass ratio of more than 10: 1, the curability of the dental composition itself may decrease, making it difficult to develop high adhesive strength. is there. On the other hand, when the water-insoluble photopolymerization initiator (B-2) is blended in a mass ratio of more than 1:10, the curability of the dental composition itself is enhanced, but the polymerization promotion of the adhesive interface portion becomes insufficient. , It may be difficult to develop high adhesive strength.

[Chemical polymerization initiator]
The dental composition of the present invention can further contain a chemical polymerization initiator, and an organic peroxide is preferably used. The organic peroxide used in the above-mentioned chemical polymerization initiator is not particularly limited, and known ones can be used. Typical organic peroxides include, for example, ketone peroxides, hydroperoxides, diacyl peroxides, dialkyl peroxides, peroxyketals, peroxyesters, peroxydicarbonates and the like. Specific examples of these organic peroxides include those described in International Publication No. 2008/08977.

[Polymer particles (C)]
The polymer particles (C) are used in the dental composition of the present invention in order to achieve both suppression of polymerization shrinkage stress and mechanical strength.

In the present invention, the polymer particles (C) are particles obtained by polymerizing a monomer and are insoluble in a dental composition, and generally known particles can be used without any limitation. The polymer particles (C) in the present invention do not dissolve in the dental composition and exist as particles, thereby exhibiting effects such as reduction of polymerization shrinkage stress. Further, in general, when light diffusivity is imparted to a dental composition, although the curing depth is greatly reduced, the use of the polymer particles (C) has the effect of reducing the polymerization shrinkage stress and high mechanical properties. A dental composition having a suitable curing depth can be obtained by suppressing a significant decrease in the curing depth in addition to achieving both strength.

The polymer particles (C) used in the present invention are crosslinked, which is a polymer of a monomer containing a monomer having two or more polymerizable groups from the viewpoint of solubility in a dental composition and strength. Polymer particles are preferred.

Examples of the monomer for synthesizing the polymer particles (C) used in the present invention include vinyl-based monomers (compounds having an ethylenic double bond) commonly used in the synthesis of polymers. In the present invention, a desired light diffusivity D can be prepared using the polymer particles (C) using a vinyl-based monomer. Specific examples of the vinyl-based monomer include a conjugated diene-based monomer; an aromatic vinyl-based monomer (for example, a styrene-based monomer, etc.); a heterocyclic vinyl-based monomer; a vinyl ester-based single Quantities; Olefin-based monomers; Vinyl ether-based monomers; Ethylene-based unsaturated carboxylic acid monomers; Vinyl cyanide-based monomers; (Meta) acrylic-based monomers (for example, (meth) acrylamide-based singles Quantities; (meth) acrylic acid alkyl ester monomers, etc.); carboxylic acid vinyl ester-based monomers; amino group-containing ethylenic monomers; vinyl halides; Examples thereof include a body (a sulfonic acid group or a phosphoric acid group-containing vinyl-based monomer). One type of polymer particles (C) may be blended alone, or two or more types may be used in combination. As the polymer particles (C) synthesized from these monomers, (meth) acrylic polymer particles and styrene polymer particles are preferable, and crosslinked (meth) acrylic polymer is preferable from the viewpoint that a desired light diffusivity D can be easily prepared. Particles and crosslinked polystyrene particles are more preferable.

Examples of the (meth) acrylic polymer particles include (meth) acrylic monomers ((meth) acrylic acid ester-based monomers, (meth) acrylamide-based monomers, (meth) acrylic nitrile, and other (meth) acrylic skeletons. Polymer particles obtained by polymerization of (monomer having) or (meth) acrylic monomer and (meth) acrylic obtained by copolymerization of a vinyl-based monomer copolymerizable therewith. Examples thereof include polymer particles containing the system monomer component as the most abundant component and having a content of at least 25 mol% or more, preferably 40 mol% or more of all the components constituting the polymer particles. (Meth) acrylic polymer particles, for example, one or two to four kinds of (meth) obtained by acrylic acid C _{1 ~} C ₁₂ alkyl ester polymers (meth) acrylic acid ester polymer particles, (meth) acrylic monomer (Meta) acrylic butadiene copolymer particles obtained by copolymerization of a polymer and butadiene, (meth) acrylic nitrile polymer particles obtained by homopolymerization of (meth) acrylic nitrile, (meth) acrylic monomer and styrene-based single Examples thereof include (meth) acrylic styrene copolymer particles obtained by polymerization with a polymer. As the (meth) acrylic polymer particles, (meth) acrylic acid ester polymer particles are preferable.

The styrene polymer particles are obtained by polymer particles of a styrene-based monomer (a monomer having a styrene skeleton) or a copolymerization of a styrene-based monomer and a vinyl-based monomer copolymerizable therewith. Examples thereof include polymer particles which are polymer particles and contain a styrene-based monomer component as the most abundant component, and the content thereof is at least 25 mol% or more, preferably 40 mol% or more of all the components constituting the polymer particles. Examples of the styrene polymer particles include polystyrene particles obtained by homopolymerization of styrene, styrene vinyl copolymer particles, styrene butadiene copolymer particles, styrene acrylic copolymer particles and the like, and polystyrene particles and styrene vinyl copolymer particles are preferable.

The polymer particles (C) in the present invention can usually be obtained by suspension polymerization or emulsion polymerization, or organic fillers (polymer particles obtained by polymerizing a monomer and then pulverizing it) can also be used. .. Further, these polymers may be modified by introducing a carboxyl group or the like into the polymer. From the viewpoint of light diffusivity, polymer particles (C) obtained by suspension polymerization or emulsion polymerization are preferable.

Examples of the (meth) acrylic monomer (monomer having a (meth) acrylic skeleton) used for the synthesis of (meth) acrylic polymer particles include (meth) acrylic acid or a salt thereof, and aliphatic (meth) acrylic. Examples thereof include at least one (meth) acrylic monomer selected from the group consisting of acid esters, aromatic (meth) acrylic acid esters, (meth) acrylamide-based monomers and (meth) acrylonitrile, and (meth) Acrylic acid, aliphatic (meth) acrylic acid ester, and aromatic (meth) acrylic acid ester are preferable.

As the monomer other than the (meth) acrylic component used for the synthesis of the (meth) acrylic polymer particles, vinyl other than the (meth) acrylic monomer copolymerizable with the (meth) acrylic monomer A system monomer can be mentioned. Examples of vinyl-based monomers other than (meth) acrylic-based monomers that can be copolymerized with (meth) acrylic-based monomers include styrene-based monomers (for example, styrene, α-methylstyrene, divinylbenzene, etc.). , Vinyl chloride, vinyl acetate, itaconic acid, crotonic acid, maleic acid, fumaric acid, ethylene, conjugated diene having 4 to 8 carbon atoms (for example, 1,3-butadiene, isoprene and chloroprene), etc. The body is preferred. (Meta) acrylic copolymer particles obtained by polymerizing these with one or two to four (meth) acrylic monomers are preferable.

The styrene-based monomer used for the synthesis of styrene polymer particles is not particularly limited as long as it is a compound having styrene as a basic skeleton, and for example, styrene; a vinyl group is formed on the benzene ring of a styrene skeleton such as divinylbenzene. Compound having two or more; Styrene compound having one or more halogen atom or alkyl group having 1 to 3 carbon atoms as a substituent on the benzene ring of the styrene skeleton such as vinyltoluene, ethylvinylbenzene, bromostyrene, chlorostyrene; or Examples of styrene compounds having an alkyl group having 1 to 3 carbon atoms as a substituent on the vinyl group of the styrene skeleton such as α-methylstyrene and α-ethylstyrene can be mentioned, and the desired light diffusivity D can be easily adjusted. Styrene and divinylbenzene are preferred.

Preferred monomers other than the styrene-based monomer that can be copolymerized with the styrene-based monomer include (meth) acrylic acid or a salt thereof, an aliphatic (meth) acrylic acid ester, and an aromatic (meth) acrylic acid. At least one (meth) acrylic monomer selected from the group consisting of esters, (meth) acrylamide monomers and (meth) acrylonitrile, vinyl chloride, vinyl acetate, itaconic acid, crotonic acid, maleic acid, fumaric acid, Examples include ethylene, conjugated diene having 4 to 8 carbon atoms (for example, 1,3-butadiene, isoprene and chloroprene), (meth) acrylic acid or a salt thereof, aliphatic (meth) acrylic acid ester, aromatic (meth). Acrylic acid esters and (meth) acrylamide-based monomers are preferable.

Examples of the material of the organic filler include polymethyl methacrylate, ethyl polymethacrylate, methyl methacrylate-ethyl methacrylate copolymer, crosslinked polymethylmethacrylate, crosslinked polyethyl methacrylate, polyamide, polyvinyl chloride, and polystyrene. , Chloroprene rubber, nitrile rubber, ethylene-vinyl acetate copolymer, styrene-butadiene copolymer, acrylonitrile-styrene copolymer, acrylonitrile-styrene-butadiene copolymer and the like. These may be used alone or as a mixture of two or more.

As the polymer particles (C), a commercially available product may be used. Commercially available products include, for example, Sekisui Plastics Co., Ltd.'s techpolymer (registered trademark) "SBX series" (SBX-4, SBX-6, SBX-8.SBX-12 (crosslinked polystyrene particles, refractive index: 1). .59, average particle size: 12 μm)), techpolymer (registered trademark) "MSX series" (crosslinked methyl methacrylate-styrene copolymer particles, refractive index: 1.495 to 1.595, average particle size: 5 μm or more ), Techpolymer (registered trademark) "MBX series" (crosslinked polymethylmethacrylate particles, refractive index: 1.49, average particle size: 12 μm), techpolymer (registered trademark) "SMX series" (methyl methacrylate and styrene) Copolymerized crosslinked fine particles, refractive index: 1.495 to 1.595, average particle size: 5 μm or more), "Lumipearl" series manufactured by Nemoto Tokushu Kagaku Co., Ltd., "Epostal (trademark) MA" series manufactured by Nippon Catalyst Co., Ltd. , "Eposter (registered trademark) MA" series and the like, and among these, those having a refractive index of 1.550 or more are preferable from the viewpoint of reducing polymerization shrinkage stress and the like.

The refractive index of the polymer particles (C) is preferably different from that of either the monomer component or the filler (D) from the viewpoint of exhibiting light diffusivity, and the monomer component and the filler before curing ( It is more preferable that it is larger than any of the refractive indexes of D). Specifically, the refractive index of the polymer particles (C) is preferably 1.550 or more, more preferably 1.555 or more, and even more preferably 1.560 or more. Further, it is preferably 1.800 or less, more preferably 1.700 or less, and further preferably 1.650 or less. When the refractive index of the polymer particles (C) is less than 1.550, the effect of reducing the polymerization shrinkage stress may be reduced due to insufficient light diffusivity. On the other hand, if it exceeds 1.800, the transparency of the dental composition may be significantly reduced. Further, from the viewpoint of light diffusivity before curing of the dental composition, the difference in refractive index between the polymer particles (C) and the total monomer mixture (monomer component) before curing is 0.020 or more. Is preferable, 0.025 or more is more preferable, 0.030 or more is further preferable, and the difference in refractive index between the polymer particles (C) and the filler (D) is preferably 0.005 or more, and 0.010 or more is preferable. More preferably, 0.015 or more is further preferable. When it is within the range of the refractive index difference, it is easier to adjust the desired light diffusivity D in combination with other components such as the content of the polymer particles (C).

In the present specification, the refractive indexes of the polymer particles (C), the filler (D), and the monomer component can be measured by an Abbe refractometer. In the case of the refractive index of the polymer particles (C) and the filler (D), it is possible to measure by partially changing JIS K 0062: 1992. Specifically, using an Abbe refractometer and using the D line of sodium as a light source. It can be measured by the immersion method at 23 ° C. As the liquid, a plurality of liquids having different refractive indexes are prepared by combining two or more kinds of liquids having a refractive index close to the assumed refractive index of the sample fillers (polymer particles (C) and filler (D)). .. The sample is suspended in each liquid in an atmosphere of 23 ° C., and the liquid that looks most transparent by macroscopic observation is selected. The refractive index of the liquid is taken as the refractive index of the sample, and the refractive index of the liquid is measured with an Abbe refractometer. The liquids that can be used are, for example, diiodomethane in which sulfur is dissolved, 1-bromonaphthalene, methyl salicylate, dimethylformamide, 1-pentanol and the like. In the case of the monomer component, it conforms to JIS K 0062: 1992, and specifically, it can be measured in an atmosphere of 23 ° C. using an Abbe refractometer and using the D line of sodium as a light source. In the case of the monomer component before curing, the measurement can be carried out as a liquid. In the case of a cured monomer component, the monomer component is made into a cured plate having a certain size and measured. The liquids that can be used are diiodomethane in which sulfur is dissolved, 1-bromonaphthalene, methyl salicylate, dimethylformamide, 1-pentanol and the like.

Examples of the shape of the polymer particles (C) include an amorphous shape and a spherical shape. From the viewpoint of reducing the polymerization shrinkage stress, it is preferable to use spherical polymer particles as the polymer particles (C). Further, when the spherical polymer particles are used, there is an advantage that the dental composition of the present invention can obtain a dental composition having excellent fluidity. Here, the spherical polymer particles are those in which the polymer particles are photographed with an electron microscope and the particles observed in the unit field of view are rounded, and the particle size in the direction orthogonal to the maximum diameter is divided by the maximum diameter. Polymer particles having an average uniformity of 0.6 or more.

The average particle size of the polymer particles (C) is preferably 0.5 μm or more, more preferably 0.7 μm or more, further preferably 1.0 μm or more, particularly preferably 1.5 μm or more, and preferably 50 μm or less, preferably 30 μm. The following is more preferable, 20 μm or less is further preferable, and 10 μm or less is particularly preferable. If the average particle size is less than 0.5 μm, the viscosity of the dental composition may increase significantly and the mechanical strength may decrease. On the other hand, when the average particle size exceeds 50 μm, the light diffusion effect of the polymer particles (C) may decrease, and the effect of reducing the polymerization shrinkage stress may decrease.

In this specification, the average particle size of the polymer particles (C) can be determined by a laser diffraction / scattering method or an electron microscope observation of the particles. Specifically, the laser diffraction / scattering method is convenient for measuring the particle size of particles of 0.1 μm or more. 0.1 μm is a value measured by the laser diffraction / scattering method.

The laser diffraction / scattering method is specifically measured by a laser diffraction type particle size distribution measuring device (SALD-2300: manufactured by Shimadzu Corporation) using a 0.2% sodium hexametaphosphate aqueous solution as a dispersion medium on a volume basis. be able to.

The content of the polymer particles (C) used in the present invention is not particularly limited, and is preferably 0.1 part by mass or more and 20 parts by mass or less, and 0.5 parts by mass or more and 15 parts by mass or less, based on 100 parts by mass of the dental composition. The following is more preferable, and 0.8 parts by mass or more and 10 parts by mass or less is further preferable. If the content is less than 0.1 parts by mass, it is difficult to adjust to a predetermined light diffusivity D, and the light diffusing effect is not sufficient, so that the reduction of polymerization shrinkage stress may not be sufficient. On the other hand, if the content exceeds 20 parts by mass, a cured product of a dental composition having high mechanical strength may not be obtained. The content of the polymer particles (C) is preferably 0.1 part by mass or more, more preferably 0.5 part by mass or more, still more preferably 1 part by mass or more, based on 100 parts by mass of the total amount of the monomer components. Further, 50 parts by mass or less is preferable, 40 parts by mass or less is more preferable, and 30 parts by mass or less is further preferable. A predetermined light diffusivity D can be obtained by blending the polymer particles (C) having a content smaller than the content of the monomer component. Further, in order to obtain a predetermined light diffusivity D, the adjustment of the refractive index difference between the monomer component and the polymer particles (C) also has an effect. The content of the polymer particles (C) is preferably 0.01 parts by mass or more, more preferably 0.05 parts by mass or more, and further preferably 0.1 parts by mass or more with respect to 100 parts by mass of the filler (D). It is preferable, 40 parts by mass or less is preferable, 30 parts by mass or less is more preferable, and 20 parts by mass or less is further preferable.

In the present invention, two or more kinds of polymer particles (C) having different materials, particle size distributions, and morphologies may be mixed or used in combination.

[Filler (D)]
The dental composition of the present invention further comprises a filler (D). The filler (D) can also overlap with the polymer particles (C), but in the present invention, the filler (D) excludes those overlapping with the polymer particles (C). The filler (D) is roughly classified into an inorganic filler and an organic-inorganic composite filler.

Materials for inorganic fillers include quartz, silica, alumina, silica-titania, silica-titania-barium oxide, silica-zirconia, silica-alumina, lanthanum glass, borosilicate glass, soda glass, barium glass, strontium glass, and glass ceramics. , Aluminosilicate glass, barium boroaluminosilicate glass, strontium boroaluminosilicate glass, fluoroaluminosilicate glass, calcium fluoroaluminosilicate glass, strontium fluoroaluminosilicate glass, barium fluoroaluminosilicate glass, strontium calcium fluoroaluminosilicate glass, itterbium oxide, Examples include silica-coated itterbium fluoride. These may also be used alone or in admixture of two or more. The shape of the inorganic filler is not particularly limited, and the particle size of the filler can be appropriately selected and used. From the viewpoint of handleability and mechanical strength of the obtained composition, the average particle size of the inorganic filler is preferably 0.001 to 50 μm, more preferably 0.001 to 10 μm. Further, as a preferred embodiment, the filler (D) is a combination of an ultrafine particle inorganic filler having an average particle size of 1 nm or more and less than 0.1 μm and an inorganic filler having an average particle size of 0.1 μm or more and 10 μm or less. Dental compositions that include. In another preferred embodiment, the filler (D) comprises a combination of an ultrafine particle inorganic filler having an average particle size of 1 nm or more and less than 0.1 μm and an inorganic filler having an average particle size of 0.1 μm or more and 1 μm or less. Examples include dental compositions. In another preferred embodiment, the filler (D) is a dental composition comprising a combination of an ultrafine particle inorganic filler having an average particle size of 1 nm or more and less than 0.1 μm and an inorganic filler having an average particle size of more than 1 μm and 10 μm or less. Things can be mentioned. Further, in another preferred embodiment, the filler (D) includes an ultrafine particle inorganic filler having an average particle size of 1 nm or more and less than 0.1 μm, an inorganic filler having an average particle size of 0.1 μm or more and 1 μm or less, and an average particle. Examples thereof include dental compositions containing a combination with an inorganic filler having a diameter of more than 1 μm and 10 μm or less.

Examples of the shape of the inorganic filler include an amorphous filler and a spherical filler. From the viewpoint of improving the mechanical strength of the composition, it is preferable to use a spherical filler as the inorganic filler. Further, when the spherical filler is used, there is an advantage that a composite resin having excellent surface smoothness can be obtained when the dental composition of the present invention is used as a self-adhesive dental composite resin. Here, the spherical filler is a photograph of the filler taken with an electron microscope, and the particles observed in the unit field of view are rounded, and the particle size in the direction orthogonal to the maximum diameter is divided by the maximum diameter to achieve average uniformity. It is a filler having a degree of 0.6 or more. The average particle size of the spherical filler is preferably 0.05 to 5 μm. If the average particle size is less than 0.05 μm, the filling rate of the spherical filler in the composition may decrease, and the mechanical strength may decrease. On the other hand, when the average particle size exceeds 5 μm, the surface area of the spherical filler decreases, and a cured product of a dental composition having high mechanical strength may not be obtained.

In order to adjust the fluidity of the dental composition, the inorganic filler may be used after surface treatment with a known surface treatment agent such as a silane coupling agent, if necessary. Examples of such surface treatment agents include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltrichlorosilane, vinyltri (β-methoxyethoxy) silane, γ-methacryloyloxypropyltrimethoxysilane, and 8-methacryloyloxyoctyltrimethoxysilane. Examples thereof include 11-methacryloyloxyundecyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, and γ-aminopropyltriethoxysilane.

The organic-inorganic composite filler used in the present invention is obtained by adding a monomer compound to the above-mentioned inorganic filler in advance, forming a paste, polymerizing, and pulverizing. As the organic-inorganic composite filler, for example, a TMPT filler (a mixture of trimethylolpropane methacrylate and a silica filler and then pulverized) can be used. The shape of the organic-inorganic composite filler is not particularly limited, and the particle size of the filler can be appropriately selected and used. From the viewpoint of handleability and mechanical strength of the obtained composition, the average particle size of the organic-inorganic composite filler is preferably 0.001 to 50 μm, more preferably 0.001 to 10 μm. ..

In this specification, the average particle size of the filler can be determined by a laser diffraction / scattering method or an electron microscope observation of the particles. Specifically, the laser diffraction / scattering method is convenient for measuring the particle size of particles of 0.1 μm or more, and the electron microscope observation is convenient for measuring the particle size of ultrafine particles of less than 0.1 μm. 0.1 μm is a value measured by the laser diffraction / scattering method.

The laser diffraction / scattering method is specifically measured by a laser diffraction type particle size distribution measuring device (SALD-2300: manufactured by Shimadzu Corporation) using a 0.2% sodium hexametaphosphate aqueous solution as a dispersion medium on a volume basis. be able to.

Specifically, for electron microscope observation, for example, an electron microscope (manufactured by Hitachi, Ltd., S-4000 type) photograph of particles is taken, and the particle size of the particles (200 or more) observed in the unit field of view of the photograph is determined. , Image analysis type particle size distribution measurement software (Mac-View; manufactured by Mountech Co., Ltd.) can be used for measurement. At this time, the particle size is obtained as an arithmetic mean value of the longest length and the shortest length of the particles, and the average primary particle size is calculated from the number of particles and the particle size.

As the filler (D) used in the present invention, two or more kinds of fillers having different materials, particle size distributions, or forms may be mixed or used in combination, and within a range that does not impair the effects of the present invention. Therefore, particles other than the filler may be unintentionally contained as impurities.

The content of the filler (D) used in the present invention is not particularly limited, and the filler (D) is preferably 0 to 2000 parts by mass with respect to 100 parts by mass of the total amount of the monomer components in the dental composition. Since the suitable content of the filler (D) varies greatly depending on the embodiment used, the filler (D) according to each embodiment will be described in addition to the description of specific embodiments of the dental composition of the present invention described later. The suitable content of D) is shown.

[Polymerization accelerator (E)]
In other embodiments, a polymerization accelerator (E) is used along with a water-insoluble photopolymerization initiator (B-2) and / or a chemical polymerization initiator. Examples of the polymerization accelerator (E) used in the present invention include amines, sulfic acid and salts thereof, borate compounds, barbituric acid derivatives, triazine compounds, copper compounds, tin compounds, vanadium compounds, halogen compounds, and aldehydes. , Thiol compounds, sulfites, bisulfites, thiourea compounds and the like.

The amines used as the polymerization accelerator (E) are divided into aliphatic amines and aromatic amines. Examples of the aliphatic amine include primary aliphatic amines such as n-butylamine, n-hexylamine and n-octylamine; and secondary aliphatic amines such as diisopropylamine, dibutylamine and N-methylethanolamine; N-Methyldiethanolamine, N-ethyldiethanolamine, Nn-butyldiethanolamine, N-lauryldiethanolamine, 2- (dimethylamino) ethylmethacrylate, N-methyldiethanolaminedimethacrylate, N-ethyldiethanolaminedimethacrylate, triethanolamine monomethacrylate , Triethanolamine dimethacrylate, triethanolamine trimethacrylate, triethanolamine, trimethylamine, triethylamine, tributylamine and other tertiary aliphatic amines. Among these, tertiary aliphatic amines are preferable from the viewpoint of curability and storage stability of the dental composition, and among them, N-methyldiethanolamine and triethanolamine are more preferably used.

Examples of the aromatic amine include N, N-bis (2-hydroxyethyl) -3,5-dimethylaniline, N, N-bis (2-hydroxyethyl) -p-toluidine, and N, N-bis. (2-Hydroxyethyl) -3,4-dimethylaniline, N, N-bis (2-hydroxyethyl) -4-ethylaniline, N, N-bis (2-hydroxyethyl) -4-isopropylaniline, N, N-bis (2-hydroxyethyl) -4-t-butylaniline, N, N-bis (2-hydroxyethyl) -3,5-diisopropylaniline, N, N-bis (2-hydroxyethyl) -3, 5-di-t-butylaniline, N, N-dimethylaniline, N, N-dimethyl-p-toluidine, N, N-dimethyl-m-toluidine, N, N-diethyl-p-toluidine, N, N- Dimethyl-3,5-dimethylaniline, N, N-dimethyl-3,4-dimethylaniline, N, N-dimethyl-4-ethylaniline, N, N-dimethyl-4-isopropylaniline, N, N-dimethyl- 4-t-butylaniline, N, N-dimethyl-3,5-di-t-butylaniline, ethyl 4- (N, N-dimethylamino) benzoate, 4- (N, N-dimethylamino) benzoic acid Methyl, 4- (N, N-dimethylamino) propyl benzoate, 4- (N, N-dimethylamino) n-butoxyethyl benzoate, 4- (N, N-dimethylamino) 2- (methacryloyloxy) benzoate ) Ethyl, 4- (N, N-dimethylamino) benzophenone, 4- (N, N-dimethylamino) butyl benzoate and the like. Among these, N, N-bis (2-hydroxyethyl) -p-toluidine, 4- (N, N-dimethylamino) ethyl benzoate, 4 At least one selected from the group consisting of-(N, N-dimethylamino) n-butoxyethyl benzoate and 4- (N, N-dimethylamino) benzophenone is preferably used.

Specific examples of sulfinic acid and its salts, borate compounds, barbituric acid derivatives, triazine compounds, copper compounds, tin compounds, vanadium compounds, halogen compounds, aldehydes, thiol compounds, sulfites, hydrogen sulfites, and thiourea compounds. Is described in International Publication No. 2008/08977.

The above-mentioned polymerization accelerator (E) may be blended alone or in combination of two or more. The content of the polymerization accelerator (E) used in the present invention is not particularly limited, but from the viewpoint of curability of the obtained dental composition, the total amount of the monomer components in the dental composition is 100 parts by mass. On the other hand, 0.001 part by mass or more is preferable, 0.01 part by mass or more is more preferable, 0.1 part by mass or more is further preferable, 30 parts by mass or less is preferable, and 10 parts by mass or less is more preferable. More preferably, it is by mass or less. If the content of the polymerization accelerator (E) is less than 0.001 part by mass, the polymerization does not proceed sufficiently, which may lead to a decrease in adhesiveness. The content of the polymerization accelerator (E) is more preferably 0.05 parts by mass or more. On the other hand, if the content of the polymerization accelerator (E) exceeds 30 parts by mass, or if the polymerization performance of the polymerization initiator itself is low, sufficient adhesiveness may not be obtained, and further, a dental composition. May cause precipitation from. Therefore, the content of the polymerization accelerator (E) is more preferably 20 parts by mass or less.

[Fluoride ion-releasing substance]
The dental composition of the present invention may further contain a fluoride ion-releasing substance. By blending a fluoride ion-releasing substance, a dental composition capable of imparting acid resistance to the dentin can be obtained. Examples of such fluorine ion-releasing substances include metal fluorides such as sodium fluoride, potassium fluoride, sodium monofluorophosphate, lithium fluoride, and itterbium fluoride. The above-mentioned fluoride ion-releasing substance may be blended alone or in combination of two or more.

In addition, dental compositions include pH adjusters, polymerization inhibitors, thickeners, colorants, fluorescent agents, fragrances, and cross-linking agents (for example, polyvalent metal ion emitting components) as long as the effects of the present invention are not impaired. Etc.) and other additives may be added. As the additive, one type may be used alone, or two or more types may be used in combination. The dental compositions of the present invention include cetylpyridinium chloride, benzalkonium chloride, (meth) acryloyloxidedecylpyridinium bromide, (meth) acryloyloxyhexadecylpyridinium chloride, (meth) acryloyloxydecylammonium chloride, triclosan and the like. May contain antibacterial substances. The dental composition of the present invention may contain known dyes and pigments as colorants. Examples of the polyvalent metal ion releasing component include metal ion releasing components belonging to Group 3 and Group 13 of the periodic table. Metals belonging to Group 3 of the periodic table include yttrium, scandium, and lanthanoids. Examples of the metal belonging to Group 13 of the periodic table include aluminum, gallium, and indium. A preferred embodiment of the present invention is a monomer having an acidic group (from the viewpoint that the crosslink density in the polymer matrix is appropriately lowered and the effect of reducing the polymerization shrinkage stress of the (meth) acrylic compound (A) is not hindered. Examples thereof include dental compositions that do not contain a cross-linking agent such as a polyvalent metal ion-releasing component that forms an ionic cross-link with B).

The dental composition of the present invention comprises a monomer (A), a polymerization initiator (B), a polymer particle (C), a filler (D) (excluding the polymer particle (C)), a polymerization accelerator (E), and the like. The amount of the components other than the polymerization inhibitor and the colorant is preferably less than 0.1 parts by mass, more preferably less than 0.01 parts by mass, out of 100 parts by mass of the dental composition. It is more preferably less than 001 parts by mass.

The dental composition of the present invention is, for example, a dental composite resin (particularly preferably a self-adhesive dental composite resin), a dental cement, a pit fissure filling material, a swaying tooth fixing material, or an orthodontic bonding material. It can be used for dental treatments such as, and above all, it is preferably used as a dental composite resin such as a self-adhesive dental composite resin, or a dental cement. At this time, the components of the dental composition of the present invention may be used as a two-bottle type or a two-paste type divided into two. Hereinafter, specific embodiments when the dental composition is applied will be shown.

<Self-adhesive dental composite resin>
One of the preferred embodiments of the dental composition of the present invention is a self-adhesive dental composite resin. The self-adhesive dental composite resin comprising the dental composition of the present invention contains a monomer (A-1) having an acidic group. When the dental composition of the present invention is used as a self-adhesive dental composite resin, the monomer (A), the polymerization initiator (B), the polymer particles (C), the filler (D) and the polymerization accelerator (E) The monomer (A) contains, a monomer (A-1) having an acidic group, a hydrophobic monomer (A-2) having no acidic group, and a hydrophilic monomer having no acidic group. It is preferable to include a monomer (A-3). The polymerization initiator (B) is preferably a photopolymerization initiator, and the polymerization initiator (B) contains a water-soluble photopolymerization initiator (B-1) and a water-insoluble photopolymerization initiator (B-2). Is more preferable. When the dental composition of the present invention is used as a self-adhesive dental composite resin, a pretreatment material may be used, but since it has self-adhesiveness, the pretreatment material is not essential, and a pretreatment material is used. It does not have to be. It can be a self-adhesive dental composite resin containing only the dental composition of the present invention without containing a pretreatment material.

Regarding the content of each component in the self-adhesive dental composite resin, 1 to 50 parts by mass of the monomer (A-1) having an acidic group, acidic in 100 parts by mass of the total amount of the monomer components in the dental composition. It preferably contains 20 to 99 parts by mass of a hydrophobic monomer (A-2) having no group and 0 to 50 parts by mass of a hydrophilic monomer (A-3) having no acidic group, and has an acidic group. Monomer (A-1) 1 to 40 parts by mass, hydrophobic monomer (A-2) having no acidic group 40 to 99 parts by mass, hydrophilic monomer having no acidic group (A-3) It is more preferable to contain 0 to 40 parts by mass, 1 to 30 parts by mass of the monomer (A-1) having an acidic group, and 60 to 99 parts by mass of a hydrophobic monomer (A-2) having no acidic group. , It is more preferable to contain 0 to 30 parts by mass of the hydrophilic monomer (A-3) having no acidic group. Further, with respect to 100 parts by mass of the total amount of the monomer component, 0.001 to 30 parts by mass of the polymerization initiator (B), 10 to 500 parts by mass of the polymer particles (C), and 50 to 2000 parts by mass of the filler (D). And 0.001 to 20 parts by mass of the polymerization accelerator (E), 0.05 to 10 parts by mass of the polymerization initiator (B), 15 to 450 parts by mass of the polymer particles (C), and the polymerization accelerator (E). ) It is more preferable to contain 0.05 to 10 parts by mass and 100 to 1500 parts by mass of the filler (D). The dental composition used as the self-adhesive dental composite resin does not have to contain the hydrophilic monomer (A-3).

<Dental composite resin>
One of the preferred embodiments of the dental composition of the present invention is a dental composite resin (excluding self-adhesive dental composite resin). The dental composite resin comprising the dental composition of the present invention does not contain a monomer (A-1) having an acidic group. When the dental composition of the present invention is used as a dental composite resin, a hydrophobic monomer having no acidic group (A-2), a hydrophilic monomer having no acidic group (A-3), It preferably contains a polymerization initiator (B), polymer particles (C), filler (D) and polymerization accelerator (E). The polymerization initiator (B) is preferably a photopolymerization initiator, and the polymerization initiator (B) contains a water-soluble photopolymerization initiator (B-1) and a water-insoluble photopolymerization initiator (B-2). Is more preferable. When the dental composition of the present invention is used as a dental composite resin, it is essential to use a dental bonding material or a pretreatment material.

Regarding the content of each component in the dental composite resin, 50 to 99 parts by mass of the hydrophobic monomer (A-2) having no acidic group, acidic in 100 parts by mass of the total amount of the monomer components in the dental composition. It is preferable that the hydrophilic monomer (A-3) having no group contains 0 to 40 parts by mass, and the hydrophobic monomer (A-2) having no acidic group has 60 to 99 parts by mass and has an acidic group. No hydrophilic monomer (A-3) It is more preferable to contain 0 to 30 parts by mass, and 70 to 99 parts by mass of the hydrophobic monomer (A-2) having no acidic group, hydrophilic having no acidic group. It is more preferable to contain 0 to 20 parts by mass of the sex monomer (A-3). Further, with respect to 100 parts by mass of the total amount of the monomer component, 0.001 to 30 parts by mass of the polymerization initiator (B), 10 to 500 parts by mass of the polymer particles (C), and 0.001 parts by mass of the polymerization accelerator (E). It preferably contains to 20 parts by mass and 50 to 2000 parts by mass of the filler (D), 0.05 to 10 parts by mass of the polymerization initiator (B), 15 to 450 parts by mass of the polymer particles (C), and a polymerization accelerator (E). ) It is more preferable to contain 0.05 to 10 parts by mass and 100 to 1500 parts by mass of the filler (D). The dental composition used as the dental composite resin does not have to contain the hydrophilic monomer (A-3).

<Dental cement>
One of the other preferred embodiments of the dental composition of the present invention is dental cement. As the dental cement, resin cement, glass ionomer cement, resin reinforced glass ionomer cement and the like are preferable. For dental cement, a self-etching primer or the like may be used as a pretreatment material. When the dental composition of the present invention is used as a dental cement, it contains a monomer (A), a polymerization initiator (B), a polymer particle (C), a filler (D) and a polymerization accelerator (E). A monomer (A-1) in which the polymer (A) has an acidic group, a hydrophobic monomer (A-2) having no acidic group, and a hydrophilic monomer (A-) having no acidic group. 3) is preferably included. Further, the polymerization initiator (B) preferably contains a chemical polymerization initiator, and more preferably contains a chemical polymerization initiator and a photopolymerization initiator. The photopolymerization initiator preferably contains a water-soluble photopolymerization initiator (B-1) and a water-insoluble photopolymerization initiator (B-2).

Regarding the content of each component in the dental cement, 0 to 50 parts by mass of the monomer (A-1) having an acidic group and no acidic group in 100 parts by mass of the total amount of the monomer components in the dental composition. It is preferable to contain 50 to 99 parts by mass of the hydrophobic monomer (A-2) and 0 to 50 parts by mass of the hydrophilic monomer (A-3) having no acidic group, and the monomer having an acidic group ( A-1) 0 to 40 parts by mass, hydrophobic monomer (A-2) having no acidic group 60 to 99 parts by mass, hydrophilic monomer having no acidic group (A-3) 0 to 40 parts by mass More preferably, it contains 0 to 30 parts by mass of a monomer (A-1) having an acidic group, 70 to 99 parts by mass of a hydrophobic monomer (A-2) having no acidic group, and an acidic group. It is more preferable to contain 0 to 30 parts by mass of the hydrophilic monomer (A-3) which does not have. Further, with respect to 100 parts by mass of the total amount of the monomer component, 0.001 to 30 parts by mass of the polymerization initiator (B), 10 to 500 parts by mass of the polymer particles (C), and 0.001 parts by mass of the polymerization accelerator (E). It preferably contains to 20 parts by mass and 50 to 2000 parts by mass of the filler (D), 0.05 to 10 parts by mass of the polymerization initiator (B), 15 to 450 parts by mass of the polymer particles (C), and a polymerization accelerator (E). ) It is more preferable to contain 0.05 to 10 parts by mass and 100 to 1500 parts by mass of the filler (D). The hydrophilic monomer (A-3) may not be contained, and in the case of the type using a pretreatment material, the monomer (A-1) having an acidic group may not be contained.

In any of the preferred embodiments of the self-adhesive dental composite resin, the dental composite resin, and the dental cement described above, the content of each component can be appropriately changed based on the description in the above specification. Any component can be added, deleted, or otherwise changed.

The present invention includes embodiments in which the above configurations are variously combined within the scope of the technical idea of the present invention as long as the effects of the present invention are exhibited.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to the following Examples. Also, not all combinations of features described in the examples are essential to the solution of the present invention. The components used in the following examples and comparative examples, their abbreviations, structures, and test methods are as follows.

[Monomer (A)]
MDP: 10-methacryloyloxydecyldihydrogen phosphate D-2.6E: 2,2-bis (4-methacryloyloxypolyethoxyphenyl) propane (with an average number of moles of ethoxy groups of 2.6)
DD: 1,10-decanediol dimethacrylate MAEA: N-methacryloyloxyethyl acrylamide

[Polymerization initiator (B)]
-Water-soluble photopolymerization initiator (B-1)
Li-TPO: Phenyl (2,4,6-trimethylbenzoyl) lithium phosphinic acid salt (compound represented by the following formula (3))

-Water-insoluble photopolymerization initiator (B-2)
CQ: dl-camphorquinone

[Polymer particles (C)]
SBX-4: Spherical crosslinked polystyrene particles (manufactured by Sekisui Plastics Co., Ltd., Techpolymer (registered trademark) SBX-4, average particle size: 4 μm, refractive index: 1.59)
SBX-6: Spherical crosslinked polystyrene particles (manufactured by Sekisui Plastics Co., Ltd., Techpolymer (registered trademark) SBX-6, average particle size: 6 μm, refractive index: 1.59)
SBX-8: Spherical crosslinked polystyrene particles (manufactured by Sekisui Plastics Co., Ltd., Techpolymer (registered trademark) SBX-8, average particle size: 8 μm, refractive index: 1.59)
MSX-6: Spherical crosslinked methyl methacrylate-styrene copolymer particles (manufactured by Sekisui Kasei Kogyo Co., Ltd., Techpolymer (registered trademark) MSX-6, average particle size: 6 μm, refractive index: 1.57)

[Filler (D)]
Inorganic filler 1: Fine particle silica "Aerosil (registered trademark) R 972" manufactured by Nippon Aerosil Co., Ltd., average particle size: 16 nm, refractive index: 1.46
Inorganic filler 2: Silane-treated silica stone powder, refractive index: 1.55
Silica stone powder (manufactured by Nitchitsu Co., Ltd., trade name: high silica) was crushed with a ball mill to obtain crushed silica stone powder. The average particle size of the obtained pulverized siliceous powder was measured by using a laser diffraction type particle size distribution measuring device (manufactured by Shimadzu Corporation, model "SALD-2300") and using a 0.2% aqueous sodium hexametaphosphate solution as a dispersion medium. When measured by the standard, it was 2.2 μm. 100 parts by mass of this crushed silica stone powder was surface-treated with 4 parts by mass of γ-methacryloyloxypropyltrimethoxysilane by a conventional method to obtain a silane-treated silica stone powder.
Inorganic filler 3: Silane-treated barium glass powder, refractive index: 1.55
Barium glass (manufactured by STEC, product code "E-3000") was pulverized with a ball mill to obtain barium glass powder. The average particle size of the obtained barium glass powder was measured using a laser diffraction type particle size distribution measuring device (manufactured by Shimadzu Corporation, model "SALD-2300") using a 0.2% aqueous sodium hexametaphosphate solution as a dispersion medium. When measured by the standard, it was 2.4 μm. 100 parts by mass of this barium glass powder was surface-treated with 3 parts by mass of γ-methacryloyloxypropyltrimethoxysilane by a conventional method to obtain a silane-treated barium glass powder.
Inorganic filler 4: Silane-treated barium glass powder, refractive index: 1.53
8235 UF 0.7 grade (SCHOTT barium glass, average particle size: 0.7 μm) 100 g, γ-methacryloyloxypropyltrimethoxysilane 6 g, and 0.3 mass% acetic acid aqueous solution 200 mL were placed in a three-necked flask for 2 hours. Stirred at room temperature. After removing water by freeze-drying, heat treatment was performed at 80 ° C. for 5 hours to obtain an inorganic filler 4.
Inorganic filler 5: Silane-treated barium glass powder, refractive index: 1.53
100 g of GM27884 NF180 grade (SCHOTT barium glass, average particle size: 0.18 μm), 13 g of γ-methacryloyloxypropyltrimethoxysilane, and 200 mL of 0.3 mass% acetic acid aqueous solution are placed in a three-necked flask at room temperature for 2 hours. Was stirred with. After removing water by freeze-drying, heat treatment was performed at 80 ° C. for 5 hours to obtain an inorganic filler 5.

[Polymerization accelerator (E)]
DABE: 4- (N, N-dimethylamino) ethyl benzoate

[Other]
BHT: 2,6-di-t-butyl-4-methylphenol (stabilizer (polymerization inhibitor))

[Example 1 and Comparative Example 1 Application of dental composition to dental composite resin and self-adhesive dental composite resin]
<Examples 1 to 12 and Comparative Examples 1 to 2>
By mixing and kneading each component shown in Table 1 at room temperature using the above-mentioned components, the dental composite resin of Examples 1 to 10 and the self-adhesive dental composite resin of Examples 11 to 12 can be obtained. And the paste (composition) of the dental composite resin of Comparative Examples 1 and 2 was prepared. Then, using these pastes, the curing depth, the polymerization shrinkage stress, the bending strength, and the light diffusivity D of the paste before curing were measured according to the methods described later. Table 1 shows the compounding ratio (parts by mass) of the dental composite resin of each Example and Comparative Example and the test results.

[Curing depth]
The paste of the dental composite resin of each Example and Comparative Example was filled in a stainless steel mold (thickness 10 mm, diameter 2 mm). The upper and lower surfaces are laminated and pressure-welded in the order of film and slide glass, and the glass plate is removed from one side. From the pressure-contact surface of the film, a dental LED light irradiator (Morita Co., Ltd., "Pencure 2000") irradiates light for 10 seconds. And cured. After removing the cured product from the mold, wipe off the uncured part, measure the curing depth from the light irradiation surface using a micrometer (manufactured by Mitutoyo Co., Ltd.), and set half of the measured value as the curing depth (N). = 5), the average value was calculated.

[Measurement of polymerization shrinkage stress]
A stainless steel washer (inner diameter 5.3 mm x 0.8 mm thickness) coated with a mold release agent was installed on a 5.0 mm thick glass plate sandblasted with 50 μm alumina powder, and each example and comparative example were installed in the washer. Filled with dental composite resin paste. Next, the excess dental composite resin paste was removed, and the dental composite resin paste was sandwiched between a separately sandblasted stainless steel jig (φ5 mm) and a glass plate.

Light irradiation was performed for 10 seconds from the glass plate side of the paste using a dental LED light irradiator (manufactured by Morita Co., Ltd., trade name "Pencure 2000") to cure the dental composite resin, and polymerization at this time. The shrinkage stress was measured with a universal testing machine (Autograph AG-I 100 kN, manufactured by Shimadzu Corporation) (N = 3), and the average value was calculated.

[Evaluation of bending properties]
Strength was evaluated by bending test according to ISO4049: 2009. Specifically, it is as follows. The paste of the dental composite resin was filled in a SUS mold (length 2 mm × width 25 mm × thickness 2 mm), and the top and bottom (2 mm × 25 mm surface) of the paste (dental composition) were pressed with a slide glass. Next, the dental composition was cured by irradiating the front and back of the paste with light through a slide glass at 5 locations on each side for 10 seconds with a dental LED light irradiator (manufactured by Morita Co., Ltd., "Pencure 2000"). The obtained cured product was subjected to a bending test at a crosshead speed of 1 mm / min using a universal testing machine (Autograph AG-I 100 kN, manufactured by Shimadzu Corporation), and the bending strength was measured (N =). 5), the average value was calculated.

[Measurement of light diffusivity D before curing]
The dental composite resins of each Example and Comparative Example were filled in a Teflon (registered trademark) mold (diameter 30 mm × thickness 0.25 mm). The upper and lower surfaces were pressure-welded with a slide glass, and the luminous intensity distribution of transmitted light was measured using a three-dimensional variable-angle photometer (“GP-200” manufactured by Murakami Color Technology Laboratory Co., Ltd., halogen light source, color temperature of about 6774K). (N = 3). The light diffusing degree D was calculated according to the following formula [I], and the average value of the obtained light diffusing degree D was calculated.
D = (I ₂₀ / cos 20 ° + I ₇₀ / cos 70 °) / (2I ₀ ) [I]
(In the formula, I represents the luminous intensity of the light transmitted through the sample, and I ₀ , I ₂₀ and I ₇₀ are the luminous intensities in the zero, 20 and 70 degree directions with respect to the direction perpendicular to the sample plate (light incident direction). Light intensity))

[Measurement of refractive index of all monomer mixture before curing]
The refractive index of the entire monomer mixture before curing was directly measured at 23 ° C. using an Abbe refractive index meter (manufactured by Atago Co., Ltd., trade name: 1T). The whole monomer mixture before curing was set in an Abbe refractive index meter, and the refractive index was measured.

As shown in Table 1, the dental composite resin (Examples 1 to 10) and the self-adhesive dental composite resin (Examples 11 to 12) according to the present invention have a bending strength of 3 mm or more as a cured product. In addition to having a low polymerization shrinkage stress of 11.2 MPa or less, it exhibited a flexural strength of 95 MPa or more, and further exhibited a light diffusivity D of 0.20 or more. From this, it was suggested that the polymerization shrinkage stress was relaxed by containing the polymer particles (C) and having a specific light diffusivity D. On the other hand, the dental composite resins (Comparative Examples 1 and 2) that do not contain the polymer particles (C) or have a light diffusivity D of less than 0.10 before curing have a polymerization shrinkage stress of 12 MPa or more and shrinkage. It was confirmed that the stress reduction was not sufficient. Further, in Comparative Example 2, although the difference in refractive index between the polymer particles (C) and the total monomer mixture before curing is the same as in Example 10, the content of the polymer particles (C) is different. As a result, the light diffusivity D before curing became less than 0.10, and the reduction of the polymerization shrinkage stress was insufficient.

The dental composition according to the present invention is suitably used as a dental composite resin, a self-adhesive dental composite resin, and a dental cement in the field of dentistry.

the incident direction 1 sample plate L ₁ incident light L a light ₀ transmitted light I ₀ transmitted light I with respect to the incident direction of the transmitted light I ₂₀ light to zero degree angle relative to the direction of the light to 20 degree angle ₇₀ transmitted light to 70 degree angle relative to the direction of light

Claims (18)

1. The dental composition containing the monomer (A), the polymerization initiator (B), the polymer particles (C), and the filler (D) (excluding the polymer particles (C)) has the following formula [I]. ], The light diffusivity D is 0.10 or more.
   D = (I ₂₀ / cos 20 ° + I ₇₀ / cos 70 °) / (2I ₀ ) [I]
   (In the formula, I represents the luminous intensity of the light transmitted through the sample, and I ₀ , I ₂₀ and I ₇₀ are the luminous intensities in the zero, 20 and 70 degree directions with respect to the direction perpendicular to the sample plate (light incident direction). Light intensity))
2. The dental composition according to claim 1, wherein the polymer particles (C) have an average particle size of 0.5 μm to 50 μm.
3. The dental composition according to claim 1 or 2, wherein the filler (D) is an inorganic filler.
4. The dental composition according to any one of claims 1 to 3, wherein the polymer particles (C) are crosslinked polymer particles.
5. The dental composition according to any one of claims 1 to 4, wherein the polymer particles (C) have a refractive index of 1.550 or more.
6. The dental composition according to any one of claims 1 to 5, wherein the content of the polymer particles (C) is 0.1 part by mass to 20 parts by mass in 100 parts by mass of the dental composition.
7. The dentistry according to any one of claims 1 to 6, wherein the content of the polymer particles (C) is 0.1 part by mass or more and 50 parts by mass or less with respect to 100 parts by mass of the total amount of the monomer components. Composition for.
8. The dental composition according to any one of claims 1 to 7, wherein the polymer particles (C) are spherical.
9. The dental composition according to any one of claims 1 to 8, wherein the difference in refractive index between the polymer particles (C) and the total monomer mixture before curing is 0.020 or more.
10. The dental composition according to any one of claims 1 to 9, wherein the polymer particles (C) are composed of (meth) acrylic polymer particles or styrene polymer particles.
11. The dental composition according to any one of claims 1 to 10, wherein the monomer (A) contains a monomer (A-1) having an acidic group.
12. The dental composition according to any one of claims 1 to 11, wherein the monomer (A) contains a hydrophobic monomer (A-2) having no acidic group.
13. The dental composition according to any one of claims 1 to 12, wherein the polymerization initiator (B) contains a water-insoluble photopolymerization initiator (B-2).
14. The dental composition according to any one of claims 1 to 13, wherein the filler (D) contains an ultrafine particle inorganic filler having an average particle diameter of 1 nm or more and less than 0.1 μm.
15. The dental composition according to any one of claims 1 to 13, wherein the filler (D) contains an inorganic filler having an average particle size of more than 1 μm and 10 μm or less.
16. A dental composite resin comprising the dental composition according to any one of claims 1 to 15.
17. A self-adhesive dental composite resin comprising the dental composition according to any one of claims 1 to 15.
18. A dental cement comprising the dental composition according to any one of claims 1 to 15.

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