Dental composition and dental adhesive composition kit using the same

Abstract

To provide a dental composition with a large 50% stress relaxation distance of shear adhesive strength immediately after curing and a large bending displacement, and to provide a dental adhesive composition kit using the same.SOLUTION: A dental composition (B) comprises a monomer (b) having no acidic group, a polymerization initiator (c), and a filler (d), the monomer (b) having no acidic group comprising a (meth)acrylic compound (b-1) having a weight average molecular weight per (meth)acrylic group of 2,000 or more and less than 20,000, and the content of the filler (d) being 0.1 to 40 mass%.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a dental composition and a dental adhesive composition kit using the same. More specifically, the present invention relates to a dental composition having a large 50% stress relaxation distance of shear bond strength immediately after curing and a large bending displacement, and a dental adhesive composition kit using the same. [Background technology]

[0002] Adhesive materials and filling materials are used for dental restorative treatment. As these adhesive materials and filling materials, dental materials made of dental polymerizable compositions containing a (meth)acrylic acid ester, a polymerization initiator, a filler, etc. are widely used.

[0003] There are various dental treatment methods using these dental materials, among which there are cases where gums have degenerated due to periodontal disease caused by aging, making it difficult to adequately support the teeth, and the teeth have become loose and prone to falling out. Such loose teeth are called mobile teeth. A method is used to treat mobile teeth by fixing the mobile teeth to healthy teeth using a dental material called a mobile tooth fixation material. Bending strain is applied during fixation until healing, but it is necessary that the tooth does not break due to the strain. On the other hand, it is also necessary to bend to a certain extent to absorb the strain so as not to break the tooth, and it is not enough to simply have high strength. In other words, the hardened material of the mobile tooth fixation material is required to have excellent toughness. The commonly used materials are chemically polymerized, but since they cannot be hardened at the desired time, a light-polymerized material that is easy to operate is desired.

[0004] In recent years, light-cured, mobile tooth fixation materials have been developed, but there are cases where the degree of mobility of the teeth is small and cases where it is large, and although light-cured products are easy to handle, they have the problem of peeling off when the teeth are very mobile. On the other hand, chemically cured types do not peel off even in cases where the teeth are very mobile, but they have the problem of being extremely difficult to handle, so there was a demand for a material that combines excellent handling with the ability to not peel off from the tooth structure. In response to this, various proposals have been made for the use of materials for fixing loose teeth (Patent Documents 1 to 3, etc.).

[0005] From the viewpoint of achieving both excellent operability and a material that does not peel off from tooth structure, Patent Document 1 proposes a dental adhesive composition that has a repeat bending test resistance of 3 or more times, thereby preventing the destruction or falling off of the hardened body and allowing for easy handling. The dental adhesive composition is excellent in strength, has good adhesion to tooth structure, and is in the form of a one-component composition for easy handling during use.

[0006] Patent Document 2 proposed a kit for fixing a loose tooth having excellent adhesion to enamel, which is made of a pretreatment material of a specific composition and a polymerizable composition kit including an acrylic block polymer having at least one polymer block that mainly contains (meth)acrylic acid ester units and functions as a hard segment, and at least one polymer block that mainly contains acrylic acid ester and functions as a soft segment.

[0007] Patent Document 3 proposed a one-component dental polymerizable composition suitable for use as a fixative for loose teeth, which has excellent operability, toughness, and adhesion to tooth structure, and in which the non-crosslinked (meth)acrylic acid ester polymer (c) has a specific composition including a homopolymer of one type of (meth)acrylic acid ester and / or a random copolymer of two or more types of (meth)acrylic acid ester. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] JP 2016-6040 A [Patent Document 2] JP 2012-46468 A [Patent Document 3] JP 2014-189504 A Summary of the Invention [Problem to be solved by the invention]

[0009] However, the inventors' investigations revealed that there is room for improvement in the conventional technology in terms of the 50% stress relaxation distance of the shear adhesive strength immediately after curing.

[0010] The "50% stress relaxation distance" is the distance from the maximum stress reached to the stress reduction to 50% in measuring the shear adhesive strength. If the 50% stress relaxation distance is large, the tooth is less likely to fall off even if it is highly mobile. Normally, for adhesives, the moment the shear bond strength reaches the maximum stress, the test piece peels off from the tooth structure, so the 50% stress relaxation distance is almost zero. In the case of materials such as adhesives, when the maximum stress is reached, not all of the material peels off, but only a portion of it peels off, resulting in a 50% greater stress relaxation distance.

[0011] In addition, in dental compositions, the adhesive strength is usually low immediately after hardening and increases as the degree of polymerization increases. Since tooth mobility is affected immediately after hardening, it has been found that the adhesive strength immediately after hardening and the 50% stress relaxation distance are important in fixing loose teeth.

[0012] As described above, in the conventional technology, fixing loose teeth poses problems specific to teeth that are highly mobile, and there is a problem that they are susceptible to the effects immediately after hardening.

[0013] Therefore, an object of the present invention is to provide a dental composition that has a large 50% stress relaxation distance of the shear adhesive strength immediately after curing and a large bending displacement, and a dental adhesive composition kit using the same. [Means for solving the problem]

[0014] As a result of extensive investigations, the present inventors discovered that a dental composition having a specific composition can solve the above problems, and after further investigations they have completed the present invention.

[0015] That is, the present invention includes the following inventions. [1] A composition comprising: a monomer (b) having no acidic group; a polymerization initiator (c); and a filler (d); the monomer (b) having no acidic group contains a (meth)acrylic compound (b-1) having a weight average molecular weight per (meth)acrylic group of 2,000 or more and less than 20,000; The dental composition (B), wherein the content of the filler (d) is 0.1 to 40 mass %. [2] The dental composition (B) according to [1], further comprising a monomer (a) having an acidic group. [3] The dental composition (B) according to [1] or [2], wherein the (meth)acrylic compound (b-1) comprises a urethane-modified (meth)acrylic compound (b-1a). [4] The dental composition (B) according to any one of [1] to [3], wherein the content of the (meth)acrylic compound (b-1) is 1 to 70 parts by mass per 100 parts by mass of the total amount of the monomers. [5] The dental composition (B) according to any one of [1] to [4], wherein at least one of the (meth)acrylic compounds (b-1) has a glass transition temperature (Tg) of lower than 40°C. [6] The dental composition (B) according to any one of [3] to [5], wherein the urethane-modified (meth)acrylic compound (b-1a) is a (meth)acrylate having a urethane bond and a structure selected from the group consisting of polyester, polycarbonate, polyurethane, polyether, polyconjugated diene, and hydrogenated polyconjugated diene. [7] The dental composition (B) according to any one of [1] to [6], wherein the dental composition (B) is of a one-component type. [8] The dental composition (B) according to any one of [1] to [6], wherein the dental composition (B) is of a two-component type. [9] The dental composition (B) according to any one of [1] to [8], wherein the dental composition (B) is a material for fixing a loose tooth.

[10] The dental composition (B) according to any one of [1] to [8], wherein the dental composition (B) is a pit and fissure sealant.

[11] The dental composition (B) according to any one of [1] to [8], wherein the dental composition (B) is an orthodontic bonding material.

[12] The dental composition according to any one of [1] to [8], wherein the dental composition (B) is a dental temporary adhesive.

[13] A dental composition (B) according to any one of [1] to [8] and a dental adhesive composition (A), A dental adhesive composition kit, comprising a dental adhesive composition (A) comprising a monomer (a) having an acidic group, a monomer (b) not having an acidic group, a polymerization initiator (c) and / or a polymerization accelerator (e), and water (f).

[14] A dental adhesive composition kit according to

[13] , in which the 50% stress relaxation distance when measuring the shear bond strength immediately after curing is 0.010 mm or more.

[15] The dental adhesive composition kit according to

[13] or

[14] , wherein the dental adhesive composition (A) is a dental bonding material.

[16] The dental adhesive composition kit according to

[13] or

[14] , wherein the dental adhesive composition (A) is a dental primer. Effect of the Invention

[0016] According to the present invention, it is possible to provide a dental composition having a large 50% stress relaxation distance of the shear adhesive strength immediately after curing and a large bending displacement, and a dental adhesive composition kit using the same. Furthermore, according to the present invention, since the 50% stress relaxation distance of the shear adhesive strength immediately after curing is large, when the cured product is peeled off, only a portion of the product peels off, and thus the cured product can be effectively prevented from falling off. Furthermore, since the hardened material has a sufficiently soft bending displacement, the hardened material can have a flexible flexibility, and even when force is applied due to tooth movement, the force can be mitigated by deformation, thereby more effectively preventing the hardened material from falling off. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] The dental composition (B) of the present invention is a dental composition (B) containing a monomer (b) having no acidic group, a polymerization initiator (c), and a filler (d), in which the monomer (b) having no acidic group contains a (meth)acrylic compound (b-1) having a weight average molecular weight per (meth)acrylic group of 2,000 or more and less than 20,000, and the dental composition (B) contains 0.1 to 40 mass% of the filler (d) relative to a total amount of 100 mass% of the dental composition (B).

[0018] In this specification, "(meth)acrylic" is a general term for methacrylic and acrylic, and the same applies to similar expressions (such as "(meth)acrylic acid" and "(meth)acrylonitrile"). In this specification, "immediately after hardening" means that the dental composition is hardened to form a hardened product, and immediately after hardening, the hardened product is placed in a container while immersed in distilled water, the container is left in an incubator set at 37°C for 15 minutes, and then the container is removed from the distilled water. In this specification, the upper and lower limits of numerical ranges (contents of each component, values ​​calculated from each component, and each physical property, etc.) can be appropriately combined. In addition, in this specification, the embodiments can be modified by combining all or part of them as appropriate. In addition, in this specification, the components (types of materials, etc.) and contents of the dental adhesive composition (A) and the dental composition (B) can be applied to both, unless otherwise specified.

[0019] The reason why the dental composition of the present invention has a large 50% stress relaxation distance of the shear bond strength immediately after hardening and a large bending displacement is not clear, but is presumed to be as follows. It is presumed that the blending of the (meth)acrylic compound (b-1) having a weight average molecular weight per (meth)acrylic group of 2,000 or more and less than 20,000 balances the crosslink density, and the blending of a specific amount of filler (d) balances the strength. As a result, the cured product has a sufficiently soft bending deformation immediately after light irradiation, and therefore, even when a force is applied due to tooth movement, the force is absorbed by deforming. Furthermore, because the 50% stress relaxation distance is large when measuring the shear bond strength immediately after hardening, even if part of the material adhered to a mobile tooth peels off, it will not peel off completely at the interface, but only part of the material will peel off, which is thought to relieve stress and make it possible to fix the mobility of even significantly mobile teeth.

[0020] In order to increase the 50% stress relaxation distance when measuring the shear bond strength immediately after curing, it is preferable for the dental adhesive composition kit to consist of a dental adhesive composition (A) containing a monomer (a) having an acidic group, a monomer (b) not having an acidic group, a polymerization initiator (c) and / or a polymerization accelerator (e), and water (f), and a dental adhesive composition (B). By applying dental adhesive composition (A) to the tooth surface before using dental composition (B), the hardening of the interface between the tooth surface and dental composition (B) is enhanced, resulting in a larger 50% stress relaxation distance when measuring the shear bond strength immediately after hardening.

[0021] The dental adhesive composition kit of the present invention has a 50% stress relaxation distance when measuring the shear bond strength immediately after curing, from the viewpoints of limiting peeling of the cured product to partial peeling and effectively preventing the cured product from falling off due to its sticky nature, and is therefore preferably 0.010 mm or more, more preferably 0.015 mm or more, even more preferably 0.020 mm or more, and particularly preferably 0.025 mm or more.

[0022] The adjustment of the 50% stress relaxation distance when measuring the shear bond strength immediately after curing by adjusting the dental composition (B) will be described below. The greater the number of functional groups of the monomer (b) that does not have an acidic group, the harder the cured product will be and the smaller the 50% stress relaxation distance will be. On the other hand, if there is too much monofunctional monomer, the cured product will become brittle, affecting mechanical strength, etc. The greater the content of (meth)acrylic compound (b-1) with a weight average molecular weight per (meth)acrylic group of 2,000 or more and less than 20,000, the larger the 50% stress relaxation distance will tend to be, but the mechanical strength will also tend to decrease. Furthermore, the greater the content of the filler (d), the greater the mechanical strength becomes, and the smaller the 50% stress relaxation distance tends to become.

[0023] Hereinafter, each component used in the dental adhesive composition (A) and the dental composition (B) of the present invention will be described.

[0024] <Monomer (a) Having an Acidic Group> The dental adhesive composition (A) contains a monomer (a) having an acidic group from the viewpoint of adhesion to tooth structure. From the viewpoint of adhesion to tooth structure, the dental composition (B) preferably further contains a monomer (a) having an acidic group. In the dental adhesive composition (A) and the dental composition (B), a radically polymerizable monomer is suitably used as the monomer (a) having an acidic group. Specific examples of the radical polymerizable monomer in the monomer (a) having an acidic group include (meth)acrylate monomers, (meth)acrylamide monomers, esters such as α-cyanoacrylic acid, (meth)acrylic acid, α-halogenated acrylic acid, crotonic acid, cinnamic acid, sorbic acid, maleic acid, and itaconic acid, vinyl esters, vinyl ethers, mono-N-vinyl derivatives, and styrene derivatives. Among these, (meth)acrylate monomers and (meth)acrylamide monomers are preferred from the viewpoint of curability. In an embodiment in which the dental composition (B) contains a monomer (a) having an acidic group, the monomer (a) having an acidic group used in the dental adhesive composition (A) and the monomer (a) having an acidic group used in the dental composition (B) may be the same or different.

[0025] Examples of the monomer (a) having an acidic group used in the present invention include monomers having at least one acidic group such as a phosphoric acid group, a pyrophosphoric acid group, a thiophosphoric acid group, a phosphonic acid group, a carboxylic acid group, or a sulfonic acid group. The monomer (a) having an acidic group may be used alone or in combination of two or more kinds. Specific examples of the monomer (a) having an acidic group are given below.

[0026] Examples of monomers having a phosphate group include 2-(meth)acryloyloxyethyl dihydrogen phosphate, 3-(meth)acryloyloxypropyl dihydrogen phosphate, 4-(meth)acryloyloxybutyl dihydrogen phosphate, 5-(meth)acryloyloxypentyl dihydrogen phosphate, 6-(meth)acryloyloxyhexyl dihydrogen phosphate, 7-(meth)acryloyloxyheptyl dihydrogen phosphate, and 8-(meth)acryloyloxyoctyl. Dihydrogen phosphate, 9-(meth)acryloyloxynonyl dihydrogen phosphate, 10-(meth)acryloyloxydecyl dihydrogen phosphate, 11-(meth)acryloyloxyundecyl dihydrogen phosphate, 12-(meth)acryloyloxydodecyl dihydrogen phosphate, 16-(meth)acryloyloxyhexadecyl dihydrogen phosphate, 20-(meth)acryloyloxyicosyl dihydrogen phosphate, bis[2-(meth)acryloyloxy] acryloyloxyethyl]hydrogen phosphate, bis[4-(meth)acryloyloxybutyl]hydrogen phosphate, bis[6-(meth)acryloyloxyhexyl]hydrogen phosphate, bis[8-(meth)acryloyloxyoctyl]hydrogen phosphate, bis[9-(meth)acryloyloxynonyl]hydrogen phosphate, bis[10-(meth)acryloyloxydecyl]hydrogen phosphate, 1,3-di(meth)acryloyloxypropyl dihydrogen Examples of suitable phosphates include 2-(meth)acryloyloxyethylphenyl hydrogen phosphate, 2-(meth)acryloyloxyethyl-(2-bromoethyl)hydrogen phosphate, 2-methacryloyloxyethyl-(4-methoxyphenyl)hydrogen phosphate, 2-methacryloyloxypropyl-(4-methoxyphenyl)hydrogen phosphate, and acid chlorides, alkali metal salts, and amine salts thereof, and a monomer having a divalent phosphoric acid group having an alkylene group having 6 to 12 carbon atoms is preferred. One preferred embodiment is a self-adhesive dental composite resin, in which the monomer (a) having an acidic group includes a monomer having a divalent phosphate group having an alkylene group having 6 to 12 carbon atoms.

[0027] Examples of monomers having a pyrophosphate group include bis[2-(meth)acryloyloxyethyl]pyrophosphate, bis[4-(meth)acryloyloxybutyl]pyrophosphate, bis[6-(meth)acryloyloxyhexyl]pyrophosphate, bis[8-(meth)acryloyloxyoctyl]pyrophosphate, bis[10-(meth)acryloyloxydecyl]pyrophosphate, and acid chlorides, alkali metal salts, and amine salts thereof.

[0028] Examples of monomers having a thiophosphate group include 2-(meth)acryloyloxyethyl dihydrogen thiophosphate, 3-(meth)acryloyloxypropyl dihydrogen thiophosphate, 4-(meth)acryloyloxybutyl dihydrogen thiophosphate, 5-(meth)acryloyloxypentyl dihydrogen thiophosphate, 6-(meth)acryloyloxyhexyl dihydrogen thiophosphate, 7-(meth)acryloyloxyheptyl dihydrogen thiophosphate, and 8-(meth)acryloyloxyoctyl dihydrogen thiophosphate. Examples of suitable acryloyloxyalkyl groups include acryloyloxyalkyl groups, 9-(meth)acryloyloxynonyl dihydrogen thiophosphate, 10-(meth)acryloyloxydecyl dihydrogen thiophosphate, 11-(meth)acryloyloxyundecyl dihydrogen thiophosphate, 12-(meth)acryloyloxydodecyl dihydrogen thiophosphate, 16-(meth)acryloyloxyhexadecyl dihydrogen thiophosphate, 20-(meth)acryloyloxyicosyl dihydrogen thiophosphate, and acid chlorides, alkali metal salts, and ammonium salts thereof.

[0029] Examples of monomers having a phosphonic acid group include 2-(meth)acryloyloxyethyl phenyl phosphonate, 5-(meth)acryloyloxypentyl-3-phosphonopropionate, 6-(meth)acryloyloxyhexyl-3-phosphonopropionate, 10-(meth)acryloyloxydecyl-3-phosphonopropionate, 6-(meth)acryloyloxyhexyl phosphonoacetate, 10-(meth)acryloyloxydecyl phosphonoacetate, and acid chlorides, alkali metal salts, and ammonium salts thereof.

[0030] Examples of the monomer having a carboxylic acid group include a monofunctional (meth)acrylic acid ester having one carboxyl group or an acid anhydride group thereof in one molecule, and a monofunctional (meth)acrylic acid ester having multiple carboxyl groups or acid anhydride groups thereof in one molecule.

[0031] Examples of monofunctional monomers having one carboxyl group or an acid anhydride group thereof in one molecule include (meth)acrylic acid, N-(meth)acryloylglycine, N-(meth)acryloylaspartic acid, 2-(meth)acryloyloxyethyl hydrogen succinate, 2-(meth)acryloyloxyethyl hydrogen phthalate, 2-(meth)acryloyloxyethyl hydrogen maleate, O-(meth)acryloyltyrosine, N-(meth)acryloyltyrosine, N-(meth)acryloyloxyethyl hydrogen phthalate, N-(meth)acryloyloxyethyl hydrogen maleate ... Examples of such compounds include acryloylphenylalanine, N-(meth)acryloyl-p-aminobenzoic acid, N-(meth)acryloyl-o-aminobenzoic acid, 2-(meth)acryloyloxybenzoic acid, 3-(meth)acryloyloxybenzoic acid, 4-(meth)acryloyloxybenzoic acid, N-(meth)acryloyl-5-aminosalicylic acid, and N-(meth)acryloyl-4-aminosalicylic acid, as well as compounds in which the carboxyl group of these compounds has been converted to an acid anhydride group.

[0032] Examples of monofunctional monomers having a plurality of carboxyl groups or acid anhydride groups thereof in one molecule include, for example, 6-(meth)acryloyloxyhexane-1,1-dicarboxylic acid, 9-(meth)acryloyloxynonane-1,1-dicarboxylic acid, 10-(meth)acryloyloxydecane-1,1-dicarboxylic acid, 11-(meth)acryloyloxyundecane-1,1-dicarboxylic acid, 12-(meth)acryloyloxydodecane-1,1-dicarboxylic acid, 13-(meth)acryloyloxytridecane-1,1-dicarboxylic acid, 4-(meth)acryloyloxyethyl trimellitate, 4-(meth)acryloyloxyethyl trimellitate anhydride ... Examples of the acryloyloxyethyl ester include oxybutyl trimellitate, 4-(meth)acryloyloxyhexyl trimellitate, 4-(meth)acryloyloxydecyl trimellitate, 2-(meth)acryloyloxyethyl-3'-(meth)acryloyloxy-2'-(3,4-dicarboxybenzoyloxy)propyl succinate, 6-(meth)acryloyloxyethyl naphthalene-1,2,6-tricarboxylic anhydride, 6-(meth)acryloyloxyethyl naphthalene-2,3,6-tricarboxylic anhydride, 4-(meth)acryloyloxyethyl carbonylpropionoyl-1,8-naphthalic anhydride, and 4-(meth)acryloyloxyethyl naphthalene-1,8-tricarboxylic anhydride.

[0033] An example of the monomer having a sulfonic acid group is 2-sulfoethyl (meth)acrylate.

[0034] Among the above-mentioned monomers (a) having an acidic group, from the viewpoint of good adhesive strength when used as the dental adhesive composition (A) or the dental composition (B), it is preferable to contain a monomer having a phosphoric acid group or a monomer having a carboxylic acid group, and examples of the monomers (a) having an acidic group include 2-(meth)acryloyloxyethyl dihydrogen phosphate, 3-(meth)acryloyloxypropyl dihydrogen phosphate, 4-(meth)acryloyloxybutyl dihydrogen phosphate, 5-(meth)acryloyloxypentyl dihydrogen phosphate, 6-(meth)acryloyloxyhexyl dihydrogen phosphate, 7-(meth)acryloyloxyheptyl dihydrogen phosphate, 8-(meth)acryloyloxyhexyl dihydrogen phosphate, 9-(meth)acryloyloxyheptyl dihydrogen phosphate, 10-(meth)acryloyloxyhexyl dihydrogen phosphate, 11-(meth)acryloyloxyheptyl dihydrogen phosphate, 12-(meth)acryloyloxyhexyl dihydrogen phosphate, 13-(meth)acryloyloxyheptyl dihydrogen phosphate, 14-(meth)acryloyloxyheptyl dihydrogen phosphate, 15-(meth)acryloyloxyheptyl dihydrogen phosphate, 16-(meth)acryloyloxyheptyl dihydrogen phosphate, 17-(meth)acryloyloxyheptyl dihydrogen phosphate, 18-(meth)acryloyloxyheptyl dihydrogen phosphate, 19-(meth)acryloyloxyheptyl dihydrogen phosphate, 20-(meth)acryloyloxyheptyl dihydrogen phosphate, 21-(meth)acryloyloxyheptyl dihydrogen phosphate, 22-(meth)acryloyloxyheptyl dihydrogen phosphate, 23-(meth)acryloyl Acryloyloxyoctyl dihydrogen phosphate, 9-(meth)acryloyloxynonyl dihydrogen phosphate, 10-(meth)acryloyloxydecyl dihydrogen phosphate, 11-(meth)acryloyloxyundecyl dihydrogen phosphate, 12-(meth)acryloyloxydodecyl dihydrogen phosphate, 16-(meth)acryloyloxyhexadecyl dihydrogen phosphate, 20-(meth)acryloyloxyicosyl dihydrogen phosphate, 4-(meth)acryloyloxyethyl trimellitate anhydride, 4-(meth)acryloyloxyethyl trimellitate, 11-(meth)acryloyloxyundecane-1,1-Dicarboxylic acid and a mixture of 2-methacryloyloxyethyl dihydrogen phosphate and bis(2-methacryloyloxyethyl)hydrogen phosphate are more preferred, and 8-(meth)acryloyloxyoctyl dihydrogen phosphate, 9-(meth)acryloyloxynonyl dihydrogen phosphate, 10-(meth)acryloyloxydecyl dihydrogen phosphate, 11-(meth)acryloyloxyundecyl dihydrogen phosphate, 12-(meth)acryloyloxydodecyl dihydrogen phosphate, 16-(meth)acryloyloxyhexadecyl dihydrogen phosphate, and 20-(meth)acryloyloxyicosyl dihydrogen phosphate are even more preferred, with 10-(meth)acryloyloxydecyl dihydrogen phosphate being particularly preferred from the viewpoint of a balance with curability.

[0035] From the viewpoint of adhesion to tooth structure, the content of the monomer (a) having an acidic group in the dental adhesive composition (A) is preferably 1 to 40 parts by mass, more preferably 2 to 35 parts by mass, even more preferably 3 to 30 parts by mass, and particularly preferably 5 to 25 parts by mass, per 100 parts by mass of the total amount of the monomers. In an embodiment in which the dental composition (B) contains a monomer (a) having an acidic group, the content of the monomer (a) having an acidic group in the dental composition (B) may be the same as the content of the monomer (a) having an acidic group in the dental adhesive composition (A). In addition, in an embodiment in which the dental composition (B) contains a monomer (a) having an acidic group, the content of the monomer (a) having an acidic group in the dental composition (B) is, from the viewpoint of adhesion to tooth structure, preferably 0.1 to 20 mass%, more preferably 1 to 15 mass%, and even more preferably 2 to 10 mass%, based on the total amount of the dental composition (B) (100 mass%). From the viewpoint of adhesion to tooth structure, the content of the monomer (a) having an acidic group in the dental adhesive composition (A) is preferably 0.1 to 50 mass%, more preferably 1 to 40 mass%, and even more preferably 2 to 30 mass%, based on 100 mass% of the total amount of the dental adhesive composition (A).

[0036] <Monomer (b) Having No Acidic Group> The monomer (b) having no acidic group in the present invention includes a (meth)acrylic compound (b-1) having a weight average molecular weight per (meth)acrylic group of 2,000 or more and less than 20,000 (hereinafter also referred to as a (meth)acrylic compound (b-1)). In addition, a hydrophobic monomer (b-2) having no acidic group and having a solubility in water at 25°C of less than 10% by mass (hereinafter sometimes simply referred to as a "hydrophobic monomer (b-2)") that does not fall under the (meth)acrylic compound (b-1) can be mentioned. In addition, a hydrophilic monomer (b-3) having no acidic group and having a solubility in water at 25°C of 10% by mass or more (hereinafter sometimes simply referred to as a "hydrophilic monomer (b-3)") that does not fall under the (meth)acrylic compound (b-1) can be mentioned. The monomer (b) having no acidic group may be used alone or in combination of two or more kinds. The monomer (b) having no acidic group (e.g., hydrophobic monomer (b-2)) contained in the dental adhesive composition (A) and the monomer (b) having no acidic group (e.g., hydrophobic monomer (b-2)) contained in the dental composition (B) may be the same or different.

[0037] (Meth)acrylic compounds (b-1) having a weight average molecular weight per (meth)acrylic group of 2,000 or more and less than 20,000 The dental composition (B) of the present invention contains a (meth)acrylic compound (b-1) having a weight average molecular weight per (meth)acrylic group of 2,000 or more and less than 20,000. The (meth)acrylic compound (b-1) is used in the dental composition (B) of the present invention in order to increase the 50% stress relaxation distance of the shear bond strength immediately after curing and to increase the bending displacement. In this specification, in the monomer (b) having no acidic group, a (meth)acrylic compound having a weight average molecular weight per (meth)acrylic group of 2,000 or more and less than 20,000 is regarded as a (meth)acrylic compound (b-1) regardless of its solubility in water at 25°C.

[0038] The (meth)acrylic compound (b-1) can be roughly classified into two types: urethane-modified (meth)acrylic compounds (b-1a) and (meth)acrylic compounds not having a urethane skeleton (b-1b). Due to the ease of introducing (meth)acrylic groups and the desired crosslinking density, when used in combination with the dental adhesive composition (A), the 50% stress relaxation distance when measuring the shear bond strength immediately after curing becomes large, so that even if the cured product of the dental composition (B) adhered to a mobile tooth partially peels off, the peeling does not occur completely at the interface, but only partially. Furthermore, the cured product has a sufficiently soft bending displacement immediately after light irradiation, and can relieve the force by deforming even when a force due to mobile teeth is applied, and also has excellent mechanical strength when combined with a specific amount of filler (d). Therefore, it is preferable that the (meth)acrylic compound (b-1) contained in the dental composition (B) contains a urethane-type (meth)acrylic compound (b-1a). The urethane-modified (meth)acrylic compound (b-1a) can be easily synthesized, for example, by adding a polyol containing a polymer skeleton described later, a compound having an isocyanate group (-NCO), and a (meth)acrylic compound having a hydroxyl group (-OH). The urethane-modified (meth)acrylic compound (b-1a) can be easily synthesized by ring-opening addition reaction of a (meth)acrylic compound having a hydroxyl group with lactone or alkylene oxide, and then adding the resulting compound having a hydroxyl group at one end to a compound having an isocyanate group. The (meth)acrylic compound (b-1b) without a urethane skeleton can be obtained, for example, by dehydration condensation reaction of a polymer of a monomer having a hydroxyl group with (meth)acrylic acid.

[0039] · Urethane (meth)acrylic compound (b-1a) The urethane-modified (meth)acrylic compound (b-1a) is preferably a (meth)acrylate having a urethane bond and a structure (polymer skeleton) selected from the group consisting of polyesters, polycarbonates, polyurethanes, polyethers, polyconjugated dienes, and hydrogenated polyconjugated dienes, and more preferably a (meth)acrylate having a urethane bond and at least one structure selected from the group consisting of polyesters, polycarbonates, polyurethanes, polyethers, polyconjugated dienes, and hydrogenated polyconjugated dienes having a structure derived from an aliphatic diol unit having 4 to 18 carbon atoms and a branched structure in one molecule.

[0040] In the above structure, examples of the polyester include copolymers of dicarboxylic acids (aromatic dicarboxylic acids such as phthalic acid and isophthalic acid; unsaturated aliphatic dicarboxylic acids such as maleic acid) and aliphatic diols having 2 to 18 carbon atoms, copolymers of dicarboxylic acids (saturated aliphatic dicarboxylic acids such as adipic acid and sebacic acid) and aliphatic diols having 2 to 18 carbon atoms, β-propiolactone polymers, γ-butyrolactone polymers, δ-valerolactone polymers, ε-caprolactone polymers, and copolymers thereof. Of these, copolymers of dicarboxylic acids (aromatic dicarboxylic acids such as phthalic acid and isophthalic acid; unsaturated aliphatic dicarboxylic acids such as maleic acid) and aliphatic diols having 2 to 12 carbon atoms, and copolymers of dicarboxylic acids (saturated aliphatic dicarboxylic acids such as adipic acid and sebacic acid) and aliphatic diols having 2 to 12 carbon atoms are preferred. Examples of the polycarbonate include polycarbonates derived from an aliphatic diol having 2 to 18 carbon atoms, polycarbonates derived from bisphenol A, and polycarbonates derived from an aliphatic diol having 2 to 18 carbon atoms and bisphenol A. Of these, polycarbonates derived from an aliphatic diol having 2 to 12 carbon atoms, polycarbonates derived from bisphenol A, and polycarbonates derived from an aliphatic diol having 2 to 12 carbon atoms and bisphenol A are preferred. Examples of polyurethane include polymers of aliphatic diols having 2 to 18 carbon atoms and diisocyanates having 1 to 18 carbon atoms, and polymers of aliphatic diols having 2 to 12 carbon atoms and diisocyanates having 1 to 12 carbon atoms are preferred. Examples of polyethers include polyethylene glycol, polypropylene glycol, polybutylene glycol, and poly(1-methylbutylene glycol). Examples of polyconjugated dienes and hydrogenated polyconjugated dienes include 1,4-polybutadiene, 1,2-polybutadiene, polyisoprene, poly(butadiene-isoprene), poly(butadiene-styrene), poly(isoprene-styrene), polyfarnesene, and hydrogenated products thereof. Among these, the structures of polyester, polycarbonate, and polyconjugated diene are preferred in terms of excellent mechanical strength and water resistance. In the production of the urethane-modified (meth)acrylic compound (b-1a), a polyol having the above-mentioned polymer skeleton can be used, and it is preferable to use a polyol having the above-mentioned polymer skeleton.

[0041] Examples of compounds having an isocyanate group include hexamethylene diisocyanate (HDI), tolylene diisocyanate (TDI), xylylene diisocyanate (XDI), diphenylmethane diisocyanate (MDI), isophorone diisocyanate (IPDI), trimethylhexamethylene diisocyanate (TMHMDI), tricyclodecane diisocyanate (TCDDI), and adamantane diisocyanate (ADI).

[0042] Examples of the (meth)acrylic compound having a hydroxyl group include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, 10-hydroxydecyl (meth)acrylate, 3-chloro-2-hydroxypropyl (meth)acrylate, 2-hydroxy-3-phenoxypropyl (meth)acrylate, glycerin mono(meth)acrylate, and 2-hydroxy-3-acryloyloxypropyl (meth)acrylate. hydroxy(meth)acrylate compounds such as dipentaerythritol tri(meth)acrylate, 2,2-bis[4-[3-(meth)acryloyloxy-2-hydroxypropoxy]phenyl]propane, 1,2-bis[3-(meth)acryloyloxy-2-hydroxypropoxy]ethane, pentaerythritol tri(meth)acrylate, and dipentaerythritol tri- or tetra(meth)acrylate; and hydroxy(meth)acrylamide compounds such as N-hydroxyethyl(meth)acrylamide and N,N-bis(2-hydroxyethyl)(meth)acrylamide. When the desired urethane-modified (meth)acrylic compound (b-1a) is a (meth)acrylate compound, it can be produced by selecting a hydroxy(meth)acrylate compound.

[0043] Examples of the aliphatic diol having 4 to 18 carbon atoms and a branched structure include 2-methyl-1,3-propanediol, 2,2-diethyl-1,3-propanediol, 1,3-butanediol, 2-methyl-1,4-butanediol, neopentyl glycol, 3-methyl-1,5-pentanediol, 2-methyl-1,8-octanediol, 2,7-dimethyl-1,8-octanediol, 2-methyl-1,9-nonanediol, 2,8-dimethyl-1,9-nonanediol, 2-methyl-1,10-decanediol, 2,9-dimethyl-1,10-decanediol, and 2-methyl-1,11-undecandiol. Examples of the dimethyl-1,15-pentadecanediol include 2,14-dimethyl-1,15-pentadecanediol, 2,14-dimethyl-1,15-pentadecanediol, 2-methyl-1,16-hexadecanediol, and 2,15-dimethyl-1,16-hexadecanediol. Among these, from the viewpoint of excellent curing properties of the self-adhesive dental composite resin, it is preferable to use an aliphatic diol having 5 to 12 carbon atoms and a methyl group as a side chain, such as 2-methyl-1,4-butanediol, 3-methyl-1,5-pentanediol, 2-methyl-1,8-octanediol, 2,7-dimethyl-1,8-octanediol, 2-methyl-1,9-nonanediol, or 2,8-dimethyl-1,9-nonanediol, as the polyol component, and 2-methyl-1,4-butanediol, 3-methyl-1,5-pentanediol, 2-methyl-1,8-octanediol, or 2,7-dimethyl-1,8-octanediol are more preferable, and 3-methyl-1,5-pentanediol and 2-methyl-1,8-octanediol are even more preferable.

[0044] The addition reaction between a compound having an isocyanate group and a (meth)acrylic compound having a hydroxyl group can be carried out according to a known method, and there is no particular limitation.

[0045] The urethane-modified (meth)acrylic compound (b-1a) may be any combination of a polyol having at least one structure selected from the group consisting of polyester, polycarbonate, polyurethane, polyether, polyconjugated diene, and hydrogenated polyconjugated diene, a compound having an isocyanate group, and a (meth)acrylic compound having a hydroxyl group.

[0046] (Meth)acrylic compounds that do not have a urethane skeleton (b-1b) The (meth)acrylic compound (b-1b) having no urethane skeleton preferably has a structure (polymer skeleton) selected from the group consisting of polyester, polycarbonate, polyurethane, polyether, polyconjugated diene, and hydrogenated polyconjugated diene. In the above structure, examples of the polyester include copolymers of dicarboxylic acids (aromatic dicarboxylic acids such as phthalic acid and isophthalic acid; unsaturated aliphatic dicarboxylic acids such as maleic acid) and aliphatic diols having 2 to 18 carbon atoms, copolymers of dicarboxylic acids (saturated aliphatic dicarboxylic acids such as adipic acid and sebacic acid) and aliphatic diols having 2 to 18 carbon atoms, β-propiolactone polymers, γ-butyrolactone polymers, δ-valerolactone polymers, ε-caprolactone polymers, and copolymers thereof. Of these, copolymers of dicarboxylic acids (aromatic dicarboxylic acids such as phthalic acid and isophthalic acid; unsaturated aliphatic dicarboxylic acids such as maleic acid) and aliphatic diols having 2 to 12 carbon atoms, and copolymers of dicarboxylic acids (saturated aliphatic dicarboxylic acids such as adipic acid and sebacic acid) and aliphatic diols having 2 to 12 carbon atoms are preferred. Examples of the polycarbonate include polycarbonates derived from an aliphatic diol having 2 to 18 carbon atoms, polycarbonates derived from bisphenol A, and polycarbonates derived from an aliphatic diol having 2 to 18 carbon atoms and bisphenol A. Of these, polycarbonates derived from an aliphatic diol having 2 to 12 carbon atoms, polycarbonates derived from bisphenol A, and polycarbonates derived from an aliphatic diol having 2 to 12 carbon atoms and bisphenol A are preferred. Examples of polyurethane include polymers of aliphatic diols having 2 to 18 carbon atoms and diisocyanates having 1 to 18 carbon atoms, and polymers of aliphatic diols having 2 to 12 carbon atoms and diisocyanates having 1 to 12 carbon atoms are preferred. Examples of polyethers include polyethylene glycol, polypropylene glycol, polybutylene glycol, and poly(1-methylbutylene glycol). Examples of polyconjugated dienes and hydrogenated polyconjugated dienes include 1,4-polybutadiene, 1,2-polybutadiene, polyisoprene, poly(butadiene-isoprene), poly(butadiene-styrene), poly(isoprene-styrene), polyfarnesene, and hydrogenated products thereof. Among these, the structures of polyester, polycarbonate, and polyconjugated diene are preferred in terms of excellent flexibility and water resistance. The polyol having the above-mentioned polymer skeleton can be used to produce the (meth)acrylic compound (b-1b) that does not have a urethane skeleton. By adjusting the skeleton and molecular weight of the structure (polymer skeleton) selected from the group consisting of polyester, polycarbonate, polyurethane, polyether, polyconjugated diene, and hydrogenated polyconjugated diene, the glass transition temperature and acetone solubility of the (meth)acrylic compound (b-1b) having no urethane skeleton can be adjusted.

[0047] Examples of the (meth)acrylic compound having a hydroxyl group include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, 10-hydroxydecyl (meth)acrylate, 3-chloro-2-hydroxypropyl (meth)acrylate, 2-hydroxy-3-phenoxypropyl (meth)acrylate, glycerin mono(meth)acrylate, and 2-hydroxy-3-acryloyloxypropyl (meth)acrylate. hydroxy(meth)acrylate compounds such as dipentaerythritol tri(meth)acrylate, 2,2-bis[4-[3-(meth)acryloyloxy-2-hydroxypropoxy]phenyl]propane, 1,2-bis[3-(meth)acryloyloxy-2-hydroxypropoxy]ethane, pentaerythritol tri(meth)acrylate, and dipentaerythritol tri- or tetra(meth)acrylate; and hydroxy(meth)acrylamide compounds such as N-hydroxyethyl(meth)acrylamide and N,N-bis(2-hydroxyethyl)(meth)acrylamide. When the desired (meth)acrylic compound (b-1b) is a (meth)acrylate compound, it can be produced by selecting a hydroxy(meth)acrylate compound.

[0048] Examples of the (meth)acrylic compound (b-1b) not having a urethane skeleton include reaction products of any combination of the above-mentioned polyol having at least one structure selected from the group consisting of polyester, polycarbonate, polyurethane, polyether, polyconjugated diene, and hydrogenated polyconjugated diene, and a (meth)acrylic compound having a hydroxyl group.

[0049] The weight average molecular weight (Mw) of the (meth)acrylic compound (b-1) is preferably 1,000 to 80,000, more preferably 2,000 to 50,000, and even more preferably 3,000 to 20,000, from the viewpoint of improving the 50% stress relaxation distance and bending displacement. In the present invention, the weight average molecular weight (Mw) means a polystyrene-equivalent weight average molecular weight determined by gel permeation chromatography (GPC).

[0050] The weight average molecular weight per (meth)acrylic group in the (meth)acrylic compound (b-1) is 2,000 or more and less than 20,000, preferably 2,500 or more and 17,500 or less, more preferably 3,000 or more and 16,000 or less, and even more preferably 3,500 or more and 15,000 or less. When the weight average molecular weight per (meth)acrylic group of the (meth)acrylic compound (b-1) is within the above range, appropriate crosslinking occurs, and in addition to improving the 50% stress relaxation distance and bending displacement, it becomes possible to more effectively maintain mechanical strength. Furthermore, when the (meth)acrylic compound (b-1) contains a polymerizable group other than the (meth)acrylic group, such as a vinyl group or a styrene group, the desired 50% stress relaxation distance and bending displacement may not be obtained depending on the polymerization form. Therefore, the number of polymerizable groups other than the (meth)acrylic group in the (meth)acrylic compound (b-1) is preferably 2 or less, and more preferably 0.

[0051] The (meth)acrylic compound (b-1) may contain at least one glass transition temperature (hereinafter sometimes simply abbreviated as "Tg") of less than 40°C. The Tg is not particularly limited as long as it is less than 40°C, but from the viewpoint of obtaining superior 50% stress relaxation distance of shear adhesive strength immediately after curing and bending displacement, it is preferably in the temperature range of -100°C to 30°C, more preferably in the temperature range of -75°C to 15°C, and even more preferably in the temperature range of -60°C to 10°C. If the (meth)acrylic compound (b-1) only has a Tg of 40° C. or more, it will be in a glassy state at the temperature during polymerization, and therefore will not exhibit the excellent effects in the 50% stress relaxation distance of the shear adhesive strength immediately after curing and in the bending displacement. As described below, the (meth)acrylic compound (b-1) may have multiple Tgs, and in that case, one of the Tgs may be less than 40° C., and the other Tgs may be in a temperature range of 40° C. or more. For example, the (meth)acrylic compound (b-1) may have two Tgs, one of which is −42° C. and the other is 44.6° C. In an embodiment, in order to adjust the glass transition region to less than 40° C., it is preferable to use a (meth)acrylic compound (b-1) that does not contain an aromatic ring in its skeleton in order to prevent the glass transition temperature from becoming high. In another embodiment, in order to adjust the glass transition region to less than 40° C., a (meth)acrylic compound (b-1) that does not contain a cyclic structure (aromatic ring, heterocyclic ring, alicyclic structure) in the skeleton is preferred.

[0052] The glass transition temperature (Tg) in the present invention is the midpoint glass transition temperature (T mg The glass transition temperature (Tg) used in the present invention is specifically determined by measurement based on JIS K 7121-1987 (2012 supplement).

[0053] Commercially available products may be used as the (meth)acrylic compound (b-1). Examples of commercially available products include urethane polymers having a polymerizable group at the end, such as the "Art Resin" series (UN-7600, UN-7700) manufactured by Negami Chemical Industrial Co., Ltd., and the "Kuraprene" series (LIR-30, LIR-50, LIR-390, LIR-403, LIR-410, UC-102M, UC-203M, LIR-700, LB) having a polyisoprene skeleton or a polybutadiene skeleton, manufactured by Kuraray Co., Ltd. R-302, LBR-307, LBR-305, LBR-352, LBR-361, L-SBR-820, L-SBR-841), polyols manufactured by Kuraray Co., Ltd. (P-6010, P-5010, P-4010, P-3010, P-2010, P-1010, F-3010, F2010, F-1010, P-2011, P-1020, P-2020, P-530, P-2030, P-2050, C-2090), Examples of the polybutadiene include liquid polybutadiene "NISSO-PB" (B-1000, B-2000, B-3000, BI-2000, BI-3000, G-1000, G-2000, G-3000, GI-1000, GI-2000, GI-3000, TEAI-1000, TE-2000, TE-4000, JP-100, JP-200) manufactured by Nippon Soda Co., Ltd., and UN-7600, UN-7700, LBR-302, LB R-307, LBR-305, LBR-352, LBR-361, L-SBR-820, UC-102M, UC-203M, C-2090, P-2020, P-2050, B3000, BI-2000, BI-3000, TEAI-1000, TE-2000, and TE-4000 are preferred, and from the viewpoint of flexibility, UN-7600, UN-7700, UC-102M, TE-2000, and TE-4000 are more preferred.

[0054] The content of the (meth)acrylic compound (b-1) in the dental composition (B) of the present invention is preferably 1 to 70 parts by mass, more preferably 2.5 to 60 parts by mass, even more preferably 3 to 55 parts by mass, and particularly preferably 5 to 50 parts by mass, from the viewpoint of a large 50% stress relaxation distance of the shear bond strength immediately after curing and a large bending displacement, per 100 parts by mass of the total amount of monomers. From the viewpoints of achieving a large 50% stress relaxation distance of the shear bond strength immediately after curing and a large bending displacement, the content of the (meth)acrylic compound (b-1) in the dental composition (B) is preferably 1 to 70 mass%, more preferably 5 to 60 mass%, and even more preferably 8 to 50 mass%, based on 100 mass% of the total amount of the dental composition (B). The dental adhesive composition (A) may contain a (meth)acrylic compound (b-1), but it is preferable that it does not contain such a compound.

[0055] Hydrophobic monomers without acidic groups (b-2) The hydrophobic monomer (b-2) having no acidic group improves the handleability of the dental adhesive composition (A) and the dental composition (B) and the mechanical strength (flexural strength) of the cured product, and reduces the water absorption and dissolution amounts. As the hydrophobic monomer (b-2), a radical polymerizable monomer having no acidic group and a polymerizable group is preferred, and from the viewpoint of easy radical polymerization, the polymerizable group is preferably a (meth)acryloyloxy group and / or a (meth)acrylamide group. The hydrophobic monomer (b-2) means a monomer having no acidic group and a solubility in water at 25°C of less than 10% by mass. Examples of the hydrophobic monomer (b-2) include crosslinkable monomers such as aromatic compound-based monofunctional monomers, aliphatic compound-based monofunctional monomers, aromatic compound-based bifunctional monomers, aliphatic compound-based bifunctional monomers, and trifunctional or higher monomers. The hydrophobic monomer (b-2) may be used alone or in combination of two or more types.

[0056] Examples of the monofunctional hydrophobic monomer include aliphatic compound-based monofunctional (meth)acrylate monomers such as n-stearyl (meth)acrylate; aliphatic compound-based monofunctional (meth)acrylate monomers containing ether bonds such as butoxydiethylene glycol (meth)acrylate and methoxypolyethylene glycol (meth)acrylate (average molar number of oxyethylene groups added: 9); alicyclic compound-based monofunctional (meth)acrylate monomers such as cyclohexyl (meth)acrylate, isobornyl (meth)acrylate, and dicyclopentanyl (meth)acrylate; monofunctional (meth)acrylate monomers having an aromatic ring group such as 2-phenoxyethyl (meth)acrylate and phenoxybenzyl (meth)acrylate; and (meth)acrylate monomers containing a heterocyclic group (e.g., a cyclic ether group) such as tetrahydrofurfuryl (meth)acrylate. As the monofunctional (meth)acrylate monomer having an aromatic ring group, one having one or two phenyl groups is preferred. As the (meth)acrylate monomer containing a heterocyclic group, one having one or two heterocyclic groups (e.g., cyclic ether group, etc.) is preferred. Among these, phenoxybenzyl methacrylate (commonly known as POB-MA), tetrahydrofurfuryl methacrylate (commonly known as THF-MA), and benzyl methacrylate (commonly known as BEMA) are preferred from the viewpoints of mechanical strength, a large 50% stress relaxation distance of shear adhesive strength immediately after curing, a large bending displacement, flexibility, etc.

[0057] Examples of the aromatic bifunctional hydrophobic monomer include 2,2-bis((meth)acryloyloxyphenyl)propane, 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-(meth)acryloyloxydiethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxytriethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxytetraethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxypentaethoxyphenyl)propane, and the like. 2-(4-(meth)acryloyloxydipropoxyphenyl)propane, 2-(4-(meth)acryloyloxydiethoxyphenyl)-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, from the viewpoints of mechanical strength, refractive index adjustment, and handling properties, 2,2-bis[4-(2-hydroxy-3-methacryloyloxypropoxy)phenyl]propane (commonly known as "Bis-GMA"), 2,2-bis(4-(meth)acryloyloxyethoxyphenyl)propane, 2,2-bis(4-methacryloyloxypolyethoxyphenyl)propane (average number of moles added of ethoxy groups: 2.6, commonly known as "D-2.6E"), 2,2-bis(4-(meth)acryloyloxydiethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxytriethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxytetraethoxyphenyl)propane, and 2,2-bis(4-(meth)acryloyloxypentaethoxyphenyl)propane are preferred.

[0058] Examples of the aliphatic compound-based bifunctional hydrophobic monomer include glycerol di(meth)acrylate, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, propylene glycol di(meth)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-hexanediol di(meth)acrylate, 1,10-decanediol di(meth)acrylate, and the like. Examples of such compounds include ol di(meth)acrylate, 1,2-bis(3-methacryloyloxy-2-hydroxypropoxy)ethane, 2,2,4-trimethylhexamethylene bis(2-carbamoyloxyethyl) di(meth)acrylate, N-methacryloyloxyethyl acrylamide (commonly known as "MAEA"), N-methacryloyloxypropyl acrylamide, N-methacryloyloxybutyl acrylamide, N-(1-ethyl-(2-methacryloyloxy)ethyl)acrylamide, and N-(2-(2-methacryloyloxyethoxy)ethyl)acrylamide. Among these, from the viewpoints of mechanical strength and handling properties, 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 "UDMA"), 1,10-decanediol dimethacrylate (commonly known as "DD"), and 2,2,4-trimethylhexamethylene bis(2-carbamoyloxyethyl) dimethacrylate are preferred. From the viewpoint of 50% stress relaxation distance, 1,2-bis(3-methacryloyloxy-2-hydroxypropoxy)ethane, UDMA, and DD are preferred. From the viewpoint of adhesion to tooth structure, particularly dentin, MAEA and N-methacryloyloxypropylacrylamide are preferred.

[0059] Examples of the trifunctional or higher hydrophobic monomer include trimethylolpropane tri(meth)acrylate, trimethylolethane tri(meth)acrylate, trimethylolmethane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, N,N-(2,2,4-trimethylhexamethylene)bis[2-(aminocarboxy)propane-1,3-diol]tetra(meth)acrylate, 1,7-diacryloyloxy-2,2,6,6-tetra(meth)acryloyloxymethyl-4-oxaheptane, etc. Among these, N,N-(2,2,4-trimethylhexamethylene)bis[2-(aminocarboxy)propane-1,3-diol]tetramethacrylate is preferred from the viewpoint of mechanical strength.

[0060] Among the above hydrophobic monomers (b-2), from the viewpoints of mechanical strength (bending strength), water absorption amount, solubility amount, and handleability, bifunctional hydrophobic monomers based on aromatic compounds, and bifunctional hydrophobic monomers and monofunctional hydrophobic monomers based on aliphatic compounds are preferably used. As the aromatic compound-based bifunctional monomer, Bis-GMA and D-2.6E are preferred. As the aliphatic compound-based bifunctional monomer, 3G, neopentyl glycol di(meth)acrylate, UDMA, DD, and MAEA are preferred. As the monofunctional hydrophobic monomer, THF-MA, BEMA, POB-MA, and 2-phenoxyethyl methacrylate (commonly known as PEMA) are preferable.

[0061] The hydrophobic monomer (b-2) may be used alone or in combination of two or more kinds. The content of the hydrophobic monomer (b-2) in the dental composition (B) is preferably 15 to 98 parts by mass, more preferably 30 to 95 parts by mass, and even more preferably 40 to 92 parts by mass, per 100 parts by mass of the total amount of monomers in the dental composition (B). When the content of the hydrophobic monomer (b-2) is equal to or less than the upper limit, it is easy to suppress a decrease in the mechanical strength of the dental composition (B), and when the content is equal to or more than the lower limit, it is easy to obtain the desired mechanical strength and handleability of the cured product. The content of the hydrophobic monomer (b-2) in the dental adhesive composition (A) may be the same as the content of the hydrophobic monomer (b-2) in the dental composition (B). In addition, the content of the hydrophobic monomer (b-2) in the dental composition (B) is preferably 8 to 95 mass%, more preferably 10 to 90 mass%, and even more preferably 20 to 85 mass%, based on 100 mass% of the total amount of the dental composition (B) from the viewpoints of mechanical strength and handleability. In addition, the content of the hydrophobic monomer (b-2) in the dental adhesive composition (A) is preferably 8 to 75 mass%, more preferably 10 to 70 mass%, and even more preferably 20 to 65 mass%, based on 100 mass% of the total amount of the dental adhesive composition (A), from the viewpoints of mechanical strength and handleability.

[0062] Hydrophilic monomers without acidic groups (b-3) The hydrophilic monomer (b-3) can improve the wettability of the dental adhesive composition (A) and the dental composition (B) to tooth tissue and the permeability into tooth tissue (enamel / dentin), thereby improving the adhesive strength to tooth tissue. As the hydrophilic monomer (b-3), a radical polymerizable monomer having no acidic group and a polymerizable group is preferred, and from the viewpoint of easy radical polymerization, the polymerizable group is preferably a (meth)acryloyloxy group and / or a (meth)acrylamide group. The hydrophilic monomer (b-3) means a monomer having no acidic group and a solubility in water at 25°C of 10% by mass or more, preferably a monomer having a solubility of 30% by mass or more, and more preferably a monomer that can be dissolved in water at any ratio at 25°C. As the hydrophilic monomer, a monomer having a hydrophilic group such as a hydroxyl group, an oxymethylene group, an oxyethylene group, an oxypropylene group, or an amide group is preferred.

[0063] Examples of the hydrophilic monomer (b-3) include hydrophilic monofunctional (meth)acrylate monomers such as 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)ethyltrimethylammonium chloride, and polyethylene glycol di(meth)acrylate (average number of moles of oxyethylene groups added: 9 or more); -Hydrophilic monofunctional (meth)acrylamide monomers such as 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-(meth)acryloylmorpholine, N-trihydroxymethyl-N-methyl (meth)acrylamide, N,N-dimethylacrylamide and N,N-diethylacrylamide.

[0064] Among these hydrophilic monomers (b-3), from the viewpoint of adhesion to tooth structure, 2-hydroxyethyl (meth)acrylate, 2,3-dihydroxypropyl (meth)acrylate, and hydrophilic monofunctional (meth)acrylamide monomers are preferred, and 2-hydroxyethyl (meth)acrylate, N,N-dimethylacrylamide, and N,N-diethylacrylamide are more preferred. The hydrophilic monomers (b-3) may be used alone or in combination of two or more kinds.

[0065] The content of the hydrophilic monomer (b-3) in the dental adhesive composition (A) is preferably 0 to 50 parts by mass, more preferably 0 to 40 parts by mass, and even more preferably 0 to 30 parts by mass, in 100 parts by mass of the total amount of the monomers. The content of the hydrophilic monomer (b-3) may be 0 parts by mass in 100 parts by mass of the total amount of the monomers. When the content of the hydrophilic monomer (b-3) in the dental adhesive composition (A) is equal to or more than the lower limit, a sufficient effect of improving the adhesive strength is easily obtained, and when the content is equal to or less than the upper limit, the desired mechanical strength, water absorption amount, and dissolution amount of the cured product are easily obtained. The content of the hydrophilic monomer (b-3) in the dental composition (B) may be the same as the content of the hydrophilic monomer (b-3) in the dental adhesive composition (A).

[0066] The content of the monomer (b) not having an acidic group in the dental adhesive composition (A) is preferably 60 to 99 parts by mass, more preferably 65 to 97.5 parts by mass, and even more preferably 70 to 95 parts by mass, per 100 parts by mass of the total amount of the monomers, from the viewpoints of a large 50% stress relaxation distance of the shear bond strength immediately after curing and a large bending displacement. In an embodiment in which the dental composition (B) contains a monomer (a) having an acidic group, the content of the monomer (b) not having an acidic group in the dental composition (B) is the same as the content of the monomer (b) not having an acidic group in the dental adhesive composition (A). In an embodiment in which the dental composition (B) does not contain a monomer (a) having an acidic group, the content of the monomer (b) not having an acidic group in the dental composition (B) may be 100 parts by mass per 100 parts by mass of the total amount of the monomers. From the viewpoints of achieving a large 50% stress relaxation distance of the shear bond strength immediately after curing and a large bending displacement, the content of the monomer (b) not having an acidic group in the dental adhesive composition (A) is preferably 10 to 75 mass%, more preferably 15 to 70 mass%, and even more preferably 20 to 65 mass%, based on 100 mass% of the total amount of the dental adhesive composition (A). From the viewpoints of achieving a large 50% stress relaxation distance of the shear bond strength immediately after curing and a large bending displacement, the content of the monomer (b) not having an acidic group in the dental composition (B) is preferably 60 to 99 mass%, more preferably 65 to 97.5 mass%, and even more preferably 70 to 95 mass%, based on 100 mass% of the total amount of the dental composition (B).

[0067] <Polymerization initiator (c)> To harden the monomer, the dental composition (B) contains a polymerization initiator (c). In order to harden the monomer, it is preferred that the dental adhesive composition (A) also contains a polymerization initiator (c). As the polymerization initiator (c), a photopolymerization initiator (c-1) or a chemical polymerization initiator (c-2) can be used, and each of them may be blended alone or in combination. In an embodiment in which the dental adhesive composition (A) contains a polymerization initiator (c), the polymerization initiator (c) (e.g., photopolymerization initiator (c-1)) contained in the dental adhesive composition (A) and the polymerization initiator (c) (e.g., photopolymerization initiator (c-1)) contained in the dental composition (B) may be the same or different.

[0068] The photopolymerization initiator (c-1) is classified into a water-soluble photopolymerization initiator (c-1a) and a water-insoluble photopolymerization initiator (c-1b). As the photopolymerization initiator (c-1), only the water-soluble photopolymerization initiator (c-1a) may be used, only the water-insoluble photopolymerization initiator (c-1b) may be used, or the water-soluble photopolymerization initiator (c-1a) and the water-insoluble photopolymerization initiator (c-1b) may be used in combination, but it is preferable to use them in combination.

[0069] Water-soluble photopolymerization initiator (C-1A) The water-soluble photopolymerization initiator (c-1a) improves polymerization hardening at the hydrophilic tooth surface interface, and can realize high adhesive strength. The water-soluble photopolymerization initiator (c-1a) has a solubility in water at 25°C of 10 g / L or more, preferably 15 g / L or more, more preferably 20 g / L or more, and even more preferably 25 g / L or more. By having a solubility of 10 g / L or more, the water-soluble photopolymerization initiator (c-1a) is sufficiently dissolved in water in the tooth substance at the adhesive interface, and the polymerization promotion effect is easily expressed.

[0070] Examples of the water-soluble photopolymerization initiator (c-1a) include water-soluble thioxanthones; water-soluble acylphosphine oxides; 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propan-1-one having a (poly)ethylene glycol chain introduced to the hydroxyl group, 1-hydroxycyclohexyl phenyl ketone having a (poly)ethylene glycol chain introduced to the hydroxyl group and / or phenyl group, and 1-hydroxycyclohexyl phenyl ketone having -OCHCOO - Na + a (poly)ethylene glycol chain is introduced to the hydroxyl group and / or phenyl group of 2-hydroxy-2-methyl-1-phenylpropan-1-one; a -OCH2COO is introduced to the phenyl group of 2-hydroxy-2-methyl-1-phenylpropan-1-one - Na +and α-hydroxyalkylacetophenones such as those into which the above-mentioned formula has been introduced; and α-aminoalkylphenones such as 2-methyl-1[4-(methylthio)phenyl]-2-morpholinopropan-1-one and 2-benzyl-2-(dimethylamino)-1-[(4-morpholino)phenyl]-1-butanone have been converted into quaternary ammonium salts.

[0071] Examples of the water-soluble thioxanthones include 2-hydroxy-3-(9-oxo-9H-thioxanthen-4-yloxy)-N,N,N-trimethyl-1-propanaminium chloride, 2-hydroxy-3-(1-methyl-9-oxo-9H-thioxanthen-4-yloxy)-N,N,N-trimethyl-1-propanaminium chloride, 2-hydroxy-3-(9-oxo-9H-thioxanthen-2-yloxy)-N,N,N-trimethyl-1-propanaminium chloride, 2-hydroxy-3-(9-oxo-9H-thioxanthen-2-yloxy)-N,N,N-trimethyl-1-propanaminium chloride, 2- Hydroxy-3-(3,4-dimethyl-9-oxo-9H-thioxanthen-2-yloxy)-N,N,N-trimethyl-1-propanaminium chloride, 2-hydroxy-3-(3,4-dimethyl-9H-thioxanthen-2-yloxy)-N,N,N-trimethyl-1-propanaminium chloride, 2-hydroxy-3-(1,3,4-trimethyl-9-oxo-9H-thioxanthen-2-yloxy)-N,N,N-trimethyl-1-propanaminium chloride, and the like can be used.

[0072] Examples of the water-soluble acylphosphine oxides include acylphosphine oxides represented by the following general formula (1), (2) or (3).

[0073] [ka]

[0074] [ka]

[0075] [ka]

[0076] In formulas (1), (2) and (3), R 1 ~R 9 and R 11 ~R 16 are each independently a C1 to C4 linear or branched alkyl group or a halogen atom, and 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 17 R 18 R 19 (In the formula, R 17 , R 18 , and R 19 are each independently an organic group or a hydrogen atom), n and q are each 1 or 2, X is a C1-C4 linear or branched alkylene group, and R 10 -CH(CH3)COO(C2H4O) p It is represented by CH3, and p represents an integer of 1 to 1000.

[0077] R 1 ~R 9 and R 11 ~R 16 The alkyl group is not particularly limited as long as it is a C1 to C4 linear or branched alkyl group, and examples thereof include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a 2-methylpropyl group, and a tert-butyl group. R 1 ~R 9 The alkyl group is preferably a C1 to C3 linear alkyl group, more preferably a methyl group or an ethyl group, and even more preferably a methyl group. Examples of X include a methylene group, an ethylene group, an n-propylene group, an isopropylene group, and an n-butylene group. X is preferably a C1 to C3 linear alkylene group, more preferably a methylene group or an ethylene group, and further preferably a methylene group.

[0078] When M is a pyridinium ion, examples of the substituent on the pyridine ring include a halogen atom (fluorine atom, chlorine atom, bromine atom, iodine atom), a carboxyl group, a C2-C6 linear or branched acyl group, a C1-C6 linear or branched alkyl group, a C1-C6 linear or branched alkoxy group, etc. M is 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 17 R 18 R 19 Preferred is an ammonium ion represented by the formula: (wherein the symbols have the same meanings as above). Examples of the alkali metal ion include a lithium ion, a sodium ion, a potassium ion, a rubidium ion, and a cesium ion. Examples of the alkaline earth metal ions include calcium ions, strontium ions, barium ions, and radium ions. R 17 , R 18 , and R 19 Examples of the organic group include the same as the substituents on the pyridine ring (excluding halogen atoms).

[0079] Among these, R 1 ~R 3 A compound represented by the general formula (1) in which R 4 ~R 9 A compound represented by the general formula (2) in which R 11 ~R 16In terms of storage stability and color stability in the dental adhesive composition (A) and dental composition (B), the compound represented by the general formula (3) in which all are methyl groups is particularly preferred. In addition, the ammonium ion may be ammonium ions derived from various amines. Examples of amines include ammonia, trimethylamine, diethylamine, dimethylaniline, ethylenediamine, triethanolamine, N,N-dimethylamino methacrylate, 4-(N,N-dimethylamino)benzoic acid and its alkyl esters, 4-(N,N-diethylamino)benzoic acid and its alkyl esters, and N,N-bis(2-hydroxyethyl)-p-toluidine.

[0080] R 10 From the viewpoint of adhesion, p is preferably 1 or more, more preferably 2 or more, even more preferably 3 or more, and particularly preferably 4 or more; it is preferably 1000 or less, more preferably 100 or less, even more preferably 75 or less, and particularly preferably 50 or less.

[0081] Among these water-soluble acylphosphine oxides, sodium phenyl(2,4,6-trimethylbenzoyl)phosphinate, lithium phenyl(2,4,6-trimethylbenzoyl)phosphinate, sodium bis(2,4,6-trimethylbenzoyl)phosphinate, and lithium bis(2,4,6-trimethylbenzoyl)phosphinate, and R 10 Particularly preferred is a compound represented by the general formula (2) synthesized from polyethylene glycol methyl ether methacrylate having a molecular weight of 950 corresponding to the group represented by the following formula:

[0082] The water-soluble acylphosphine oxides having such a structure can be synthesized according to known methods, and some of them are also available as commercial products. For example, they can be synthesized by the methods disclosed in JP-A-57-197289 and WO 2014 / 095724. The water-soluble photopolymerization initiator (c-1a) may be used alone or in combination of two or more.

[0083] The water-soluble photopolymerization initiator (c-1a) may be dissolved in the dental adhesive composition (A) or the dental composition (B), or may be dispersed in the form of a powder in the dental adhesive composition (A) or the dental composition (B).

[0084] When the water-soluble photopolymerization initiator (c-1a) is dispersed in the dental adhesive composition (A) or the dental composition (B) in the form of a powder, if the average particle size is too large, it is likely to settle, so it is preferably 500 μm or less, more preferably 100 μm or less, and even more preferably 50 μm or less. On the other hand, if the average particle size is too small, the specific surface area of ​​the powder becomes too large, and the amount dispersible in the dental adhesive composition (A) or the dental composition (B) decreases, so it is preferably 0.01 μm or more. That is, the average particle size of the water-soluble photopolymerization initiator (c-1a) 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.

[0085] The average particle size of each water-soluble photopolymerization initiator (c-1a) powder can be calculated as the volume average particle size after performing image analysis using image analysis type particle size distribution measurement software (Mac-View; manufactured by Mountec Co., Ltd.) based on electron microscope photographs of 100 or more particles.

[0086] When dispersing the water-soluble photopolymerization initiator (c-1a) in the form of powder, the shape of the initiator can be spherical, needle-like, plate-like, crushed, etc., but is not particularly limited. The water-soluble photopolymerization initiator (c-1a) can be prepared by a conventionally known method such as a pulverization method, a freeze-drying method, or a reprecipitation method, and from the viewpoint of the average particle size of the obtained powder, the freeze-drying method and the reprecipitation method are preferred, and the freeze-drying method is more preferred.

[0087] From the viewpoint of the hardening properties of the dental adhesive composition (A) and dental composition (B) obtained, the content of the water-soluble photopolymerization initiator (c-1a) is preferably 0.01 to 20 parts by mass relative to 100 parts by mass of the total amount of monomers in the dental adhesive composition (A) and dental composition (B); from the viewpoint of adhesion to tooth structure, the content is more preferably 0.05 to 10 parts by mass, and even more preferably 0.1 to 5 parts by mass. When the content of the water-soluble photopolymerization initiator (c-1a) is equal to or more than the lower limit, the polymerization at the adhesive interface proceeds sufficiently, and sufficient adhesive strength is easily obtained. On the other hand, when the content of the water-soluble photopolymerization initiator (c-1a) is equal to or less than the upper limit, sufficient adhesive strength is easily obtained.

[0088] Non-water-soluble photopolymerization initiator (c-1b) From the viewpoint of curability and mechanical strength, the dental adhesive composition (A) and the dental composition (B) preferably contain, in addition to the water-soluble photopolymerization initiator (c-1a), a water-insoluble photopolymerization initiator (c-1b) having a solubility in water at 25°C of less than 10 g / L (hereinafter, sometimes referred to as the water-insoluble photopolymerization initiator (c-1b)). The water-insoluble photopolymerization initiator (c-1b) used in the present invention can be a known photopolymerization initiator. The water-insoluble photopolymerization initiator (c-1b) may be used alone or in combination of two or more kinds.

[0089] Examples of the non-water-soluble photopolymerization initiator (c-1b) include (bis)acylphosphine oxides, thioxanthones, ketals, α-diketones, coumarins, anthraquinones, benzoin alkyl ether compounds, and α-aminoketone compounds other than the water-soluble photopolymerization initiator (c-1a).

[0090] Among the (bis)acylphosphine oxides, examples of the acylphosphine oxides include 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2,6-dimethoxybenzoyldiphenylphosphine oxide, 2,6-dichlorobenzoyldiphenylphosphine oxide, 2,4,6-trimethylbenzoylmethoxyphenylphosphine oxide, 2,4,6-trimethylbenzoylethoxyphenylphosphine oxide, 2,3,5,6-tetramethylbenzoyldiphenylphosphine oxide, and benzoyldi(2,6-dimethylphenyl)phosphonate. Examples of the bisacylphosphine oxides include bis(2,6-dichlorobenzoyl)phenylphosphine oxide, bis(2,6-dichlorobenzoyl)-2,5-dimethylphenylphosphine oxide, bis(2,6-dichlorobenzoyl)-4-propylphenylphosphine oxide, bis(2,6-dichlorobenzoyl)-1-naphthylphosphine oxide, bis(2,6-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, and bis(2,5,6-trimethylbenzoyl)-2,4,4-trimethylpentylphosphine oxide.

[0091] Examples of the thioxanthones include thioxanthone, 2-chlorothioxanthen-9-one, and the like.

[0092] Examples of the ketals include benzyl dimethyl ketal and benzyl diethyl ketal.

[0093] Examples of the α-diketones include diacetyl, benzil, dl-camphorquinone, 2,3-pentadione, 2,3-octadione, 9,10-phenanthrenequinone, 4,4′-oxybenzil, acenaphthenequinone, etc. Among these, dl-camphorquinone is particularly preferred from the viewpoint of having a maximum absorption wavelength in the visible light region.

[0094] Examples of the coumarins include 3,3'-carbonylbis(7-diethylaminocoumarin), 3-(4-methoxybenzoyl)coumarin, 3-thienoylcoumarin, 3-benzoyl-5,7-dimethoxycoumarin, 3-benzoyl-7-methoxycoumarin, 3-benzoyl-6-methoxycoumarin, 3-benzoyl-8-methoxycoumarin, 3-benzoylcoumarin, 7-methoxy-3-(p-nitrobenzoyl)coumarin, 3-(p-nitrobenzoyl)coumarin, 3,5-carbonylbis(7-methoxycoumarin), 3-benzoyl-6-bromo Coumarin, 3,3'-carbonylbiscoumarin, 3-benzoyl-7-dimethylaminocoumarin, 3-benzoylbenzo[f]coumarin, 3-carboxycoumarin, 3-carboxy-7-methoxycoumarin, 3-ethoxycarbonyl-6-methoxycoumarin, 3-ethoxycarbonyl-8-methoxycoumarin, 3-acetylbenzo[f]coumarin, 3-benzoyl-6-nitrocoumarin, 3-benzoyl-7-diethylaminocoumarin, 7-dimethylamino-3-(4-methoxybenzoyl)coumarin, 7-diethylamino-3-(4-methoxybenzoyl)coumarin )coumarin, 7-diethylamino-3-(4-diethylamino)coumarin, 7-methoxy-3-(4-methoxybenzoyl)coumarin, 3-(4-nitrobenzoyl)benzo[f]coumarin, 3-(4-ethoxycinnamoyl)-7-methoxycoumarin, 3-(4-dimethylaminocinnamoyl)coumarin, 3-(4-diphenylaminocinnamoyl)coumarin, 3-[(3-dimethylbenzothiazol-2-ylidene)acetyl]coumarin, 3-[(1-methylnaphtho[1,2-d]thiazol-2-ylidene)acetyl]coumarin, 3,3'-carbo nylbis(6-methoxycoumarin), 3,3'-carbonylbis(7-acetoxycoumarin), 3,3'-carbonylbis(7-dimethylaminocoumarin), 3-(2-benzothiazolyl)-7-(diethylamino)coumarin, 3-(2-benzothiazolyl)-7-(dibutylamino)coumarin, 3-(2-benzimidazolyl)-7-(diethylamino)coumarin, 3-(2-benzothiazolyl)-7-(dioctylamino)coumarin, 3-acetyl-7-(dimethylamino)coumarin, 3,3'-carbonylbis(7-dibutylamino)coumarin, 3,Examples of the compounds include those described in JP-A-9-3109 and JP-A-10-245525, such as 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]quinolizin-11-one, and 10-(2-benzothiazolyl)-2,3,6,7-tetrahydro-1,1,7,7-tetramethyl-1H,5H,11H-[1]benzopyrano[6,7,8-ij]quinolizin-11-one.

[0095] Among the above-mentioned coumarins, 3,3'-carbonylbis(7-diethylaminocoumarin) and 3,3'-carbonylbis(7-dibutylaminocoumarin) are particularly preferred.

[0096] Examples of the anthraquinones include anthraquinone, 1-chloroanthraquinone, 2-chloroanthraquinone, 1-bromoanthraquinone, 1,2-benzanthraquinone, 1-methylanthraquinone, 2-ethylanthraquinone, and 1-hydroxyanthraquinone.

[0097] Examples of the benzoin alkyl ether compound include benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, and benzoin isobutyl ether.

[0098] Examples of the α-aminoketone compounds include 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one.

[0099] Among these water-insoluble photopolymerization initiators (c-1b), it is preferable to use at least one selected from the group consisting of (bis)acylphosphine oxides, α-diketones, and coumarins. This provides a dental adhesive composition (A) and a dental composition (B) that are excellent in photocurability in the visible and near-ultraviolet regions and exhibit sufficient photocurability even when using any of the light sources, such as a halogen lamp, a light-emitting diode (LED), and a xenon lamp.

[0100] The content of the water-insoluble photopolymerization initiator (c-1b) is not particularly limited, but from the viewpoint of the curing properties of the resulting dental adhesive composition (A) and dental composition (B), the content is preferably 0.01 to 10 parts by mass, more preferably 0.05 to 7 parts by mass, and even more preferably 0.1 to 5 parts by mass, relative to 100 parts by mass of the total amount of monomers in the dental adhesive composition (A) and dental composition (B). In addition, by making the content of the water-insoluble photopolymerization initiator (c-1b) equal to or less than the upper limit, even if the polymerization performance of the water-insoluble photopolymerization initiator (c-1b) itself is low, sufficient adhesive strength is easily obtained, and further, precipitation of the polymerization initiator (c-1b) itself from the dental adhesive composition (A) and the dental composition (B) can be suppressed.

[0101] When the water-soluble photopolymerization initiator (c-1a) and the water-insoluble photopolymerization initiator (c-1b) are used in combination, the mass ratio of the water-soluble photopolymerization initiator (c-1a) to the water-insoluble photopolymerization initiator (c-1b) in the present invention [(c-1a):(c-1b)] is preferably 10:1 to 1:10, more preferably 7:1 to 1:7, even more preferably 5:1 to 1:5, and particularly preferably 3:1 to 1:3. If the water-soluble photopolymerization initiator (c-1a) is contained in a mass ratio of more than 10:1, the hardening property of the dental adhesive composition (A) and the dental composition (B) themselves is reduced, and the adhesive strength to the dentin and bending strength are reduced, so that it may be difficult to realize the effect of the present invention, which shows good cavity sealing property in a wedge-shaped defect cavity. On the other hand, if the water-insoluble photopolymerization initiator (c-1b) is contained in a mass ratio of more than 1:10, although the hardening property of the dental adhesive composition (A) and the dental composition (B) themselves is increased, the polymerization promotion at the adhesive interface becomes insufficient, so that it may be difficult to realize high adhesive strength.

[0102] Chemical polymerization initiator (c-2) The dental adhesive composition (A) and the dental composition (B) may further contain a chemical polymerization initiator (c-2) in order to enable chemical polymerization. For example, from the viewpoint of improving the sealing ability of the dental composition (B) for cavities in areas where light does not reach, the dental composition (B) preferably contains a chemical polymerization initiator (c-2). As the chemical polymerization initiator (c-2), an organic peroxide is preferably used. The organic peroxide is not particularly limited, and known organic peroxides can be used. Representative organic peroxides include, for example, ketone peroxides, hydroperoxides, diacyl peroxides, dialkyl peroxides, peroxyketals, peroxyesters, peroxydicarbonates, etc. Specific examples of these organic peroxides include those described in WO 2008 / 087977. For example, specific examples of hydroperoxides include t-butyl hydroperoxide, cumene hydroperoxide, p-diisopropylbenzene hydroperoxide, and 1,1,3,3-tetramethylbutyl hydroperoxide. The chemical polymerization initiator (c-2) may be used alone or in combination of two or more kinds.

[0103] <Filler (d)> The dental composition (B) contains a filler (d) for adjusting the handleability, adjusting the 50% stress relaxation distance, adjusting the bending displacement, and increasing the mechanical strength (bending strength, etc.) of the cured product. The dental adhesive composition (A) may contain a filler (d). Examples of such a filler (d) include an inorganic filler, an organic-inorganic composite filler, an organic filler, etc. The filler (d) may be used alone or in combination of two or more kinds. The filler (d) (e.g., an inorganic filler) contained in the dental adhesive composition (A) and the filler (d) (e.g., an inorganic filler) contained in the dental composition (B) may be the same or different.

[0104] As the material for the inorganic filler, it is preferable to use various glasses (containing silica as the main component (containing 5% or more by mass of silica, preferably 10% or more by mass of silica), and, as necessary, oxides of heavy metals, boron, aluminum, etc.). Examples of inorganic fillers include glass powders of general compositions such as fused silica, quartz, soda lime silica glass, E glass, C glass, and borosilicate glass (Pyrex (registered trademark) glass); barium glass, strontium borosilicate glass, lanthanum glass ceramics, fluoroaluminosilicate glass, various ceramics, alumina, silica-titania, silica-zirconia, ytterbium oxide, silica-coated ytterbium fluoride, aluminosilicate glass, barium boroaluminosilicate glass, calcium fluoroaluminosilicate glass, and the like. Examples of the inorganic fillers include composite oxides such as luminosilicate glass, strontium fluoroaluminosilicate glass, barium fluoroaluminosilicate glass, and strontium calcium fluoroaluminosilicate glass, diatomaceous earth, kaolin, clay minerals (such as montmorillonite), activated clay, synthetic zeolite, mica, calcium fluoride, ytterbium fluoride, yttrium fluoride, calcium phosphate, barium sulfate, zirconium oxide, titanium oxide, and hydroxyapatite. These may be used alone or in combination of two or more. Among these, quartz, silica, silica-titania, silica-zirconia, barium glass, ytterbium oxide, and silica-coated ytterbium fluoride are preferred, and quartz, silica, silica-titania, silica-zirconia, barium glass, and silica-coated ytterbium fluoride are more preferred, in that the resulting dental adhesive composition (A) and dental composition (B) have excellent mechanical strength and transparency.

[0105] From the viewpoint of the handleability and mechanical strength of the resulting dental adhesive composition (A) and dental composition (B), the average particle size of the inorganic filler is preferably 0.001 to 50 μm, more preferably 0.001 to 10 μm, and even more preferably 0.005 to 5 μm. In the present invention, when the inorganic filler is surface-treated as described below, the average particle size of the inorganic filler means the average particle size before the surface treatment. A preferred embodiment includes the dental composition (B), wherein the filler (d) is an inorganic filler. Another preferred embodiment includes a dental adhesive composition kit, in which the dental adhesive composition (A) contains a filler (d), and the filler (d) is an inorganic filler.

[0106] The inorganic filler used may be a commercially available product. Examples of commercially available products include silica such as Aerosil (registered trademark) 90, Aerosil (registered trademark) 130, Aerosil (registered trademark) 150, Aerosil (registered trademark) 200, Aerosil (registered trademark) 255, Aerosil (registered trademark) 300, Aerosil (registered trademark) 380, Aerosil (registered trademark) OX50, and Aerosil (registered trademark) R972 (all manufactured by Nippon Aerosil Co., Ltd.), barium glass such as GM27884 and 8235 (manufactured by SCHOTT), product code "E-3000" (manufactured by Estech), strontium borosilicate glass (E-4000, manufactured by ESSTECH), lanthanum glass ceramics (GM31684, manufactured by Schott), and fluoroaluminosilicate glass (GM35429, G018-091, G018-117, manufactured by Schott).

[0107] The inorganic filler may be amorphous, crystalline, or a mixture of both, but preferably contains at least an amorphous portion.

[0108] The shape of the inorganic filler is not particularly limited, and the particle size of the filler can be appropriately selected and used, and examples thereof include amorphous filler (crushed filler) and spherical filler. From the viewpoint of the handling property of the dental adhesive composition (A) and the dental composition (B), it is preferable to use a spherical filler. A spherical filler is a filler in which the particles observed within a unit field of view of a photograph of the filler taken with an electron microscope are rounded, and the average uniformity obtained by dividing the particle diameter in the direction perpendicular to the maximum diameter by the maximum diameter is 0.6 or more.

[0109] In order to adjust the mechanical strength and fluidity of the dental adhesive composition (A) and the dental composition (B), it is preferable to previously surface-treat the inorganic filler with a known surface treatment agent such as a silane coupling agent. For example, by surface-treating the hydroxyl groups present on the surface of the inorganic filler with a surface treatment agent, an inorganic filler with the hydroxyl groups surface-treated can be obtained.

[0110] Examples of the surface treatment agent include dimethoxydimethylsilane, diethoxydimethylsilane, dimethoxydiethylsilane, diethoxydiethylsilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltrichlorosilane, vinyltri(β-methoxyethoxy)silane, γ-methacryloyloxypropyltrimethoxysilane, 8-methacryloyloxyoctyltrimethoxysilane, 11-methacryloyloxyundecyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, and γ-aminopropyltriethoxysilane. Of these, dimethoxydimethylsilane, diethoxydimethylsilane, vinyltrimethoxysilane, γ-methacryloyloxypropyltrimethoxysilane, 8-methacryloyloxyoctyltrimethoxysilane, 11-methacryloyloxyundecyltrimethoxysilane, and γ-aminopropyltriethoxysilane are preferred.

[0111] The surface treatment method can be any known method without any particular limitation, for example, a method of spraying the above-mentioned surface treatment agent while vigorously stirring the inorganic filler, a method of dispersing or dissolving the inorganic filler and the above-mentioned surface treatment agent in a suitable solvent and then removing the solvent, or a method of hydrolyzing the alkoxy group of the above-mentioned surface treatment agent in an aqueous solution with an acid catalyst to convert it to a silanol group, attaching it to the inorganic filler surface in the aqueous solution, and then removing the water, etc. In any of these methods, the reaction between the inorganic filler surface and the above-mentioned surface treatment agent can be completed by heating in the range of 50 to 150 ° C., and the surface treatment can be performed. The amount of surface treatment is not particularly limited, and for example, 0.1 to 50 parts by mass of the surface treatment agent can be used for 100 parts by mass of the inorganic filler before treatment.

[0112] The organic-inorganic composite filler is obtained by adding a monomer to the inorganic filler described above in advance, forming a paste, polymerizing it, and pulverizing it. The organic-inorganic composite filler refers to a filler containing an inorganic filler and a polymer of a monomer. As the organic-inorganic composite filler, for example, a filler obtained by mixing Bis-GMA, 3G, and a surface-treated silica filler, polymerizing it, and then pulverizing it 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. The organic-inorganic composite filler may also be used alone or in combination of two or more kinds, and it is preferable that the organic-inorganic composite filler is also surface-treated from the viewpoint of mechanical strength. Examples and preferred types of surface treatment agents are the same as those of the inorganic filler. From the viewpoint of the handling property and mechanical strength of the obtained self-adhesive dental composite resin composition, the average particle size of the organic-inorganic composite filler is preferably 0.001 to 50 μm, more preferably 0.001 to 20 μm, and even more preferably 0.005 to 15 μm.

[0113] Examples of the organic filler material include polymethyl methacrylate, polyethyl methacrylate, methyl methacrylate-ethyl methacrylate copolymer, cross-linked polymethyl methacrylate, cross-linked polyethyl methacrylate, polyamide, polyvinyl chloride, polystyrene, chloroprene rubber, nitrile rubber, ethylene-vinyl acetate copolymer, styrene-butadiene copolymer, acrylonitrile-styrene copolymer, acrylonitrile-styrene-butadiene copolymer, etc., which may be used alone or as a mixture of two or more. The shape of the organic filler is not particularly limited, and the particle size of the filler can be appropriately selected and used. From the viewpoint of the handleability and mechanical strength of the obtained self-adhesive dental composite resin, the average particle size of the organic filler is preferably 0.001 to 50 μm, more preferably 0.001 to 20 μm, and even more preferably 0.005 to 15 μm.

[0114] In this specification, the average particle size of the filler can be determined by a laser diffraction scattering method or by observing the particles with an electron microscope. Specifically, the laser diffraction scattering method is convenient for measuring particle sizes of 0.1 μm or more, while electron microscope observation is convenient for measuring the particle size of ultrafine particles less than 0.1 μm. 0.1 μm is the measurement value obtained by the laser diffraction scattering method. In the case of particles formed by agglomeration of primary particles such as aggregated particles, there are an average particle size of the primary particles and an average particle size of the secondary particles, but the average particle size of the filler is the average particle size of the secondary particles with a larger particle size.

[0115] Specifically, the laser diffraction scattering method can be performed by, for example, using a laser diffraction particle size distribution analyzer (SALD-2300, manufactured by Shimadzu Corporation) and measuring on a volume basis using a 0.2% aqueous solution of sodium hexametaphosphate as a dispersion medium.

[0116] Specifically, electron microscope observation can be performed by taking a photograph of the particles with an electron microscope (S-4000 model, manufactured by Hitachi, Ltd.) and measuring the particle diameters of the particles (200 or more) observed within a unit field of view of the photograph using image analysis type particle size distribution measurement software (Mac-View (manufactured by Mountec Co., Ltd.)). At this time, the particle diameter is determined as the arithmetic mean value of the longest and shortest lengths of the particles, and the average particle diameter is calculated from the number of particles and their particle diameters.

[0117] From the viewpoints of 50% stress relaxation distance and bending displacement, the content of the filler (d) in the dental composition (B) is in the range of 0.1 to 40 mass%, preferably in the range of 0.5 to 30 mass%, more preferably in the range of 1 to 20 mass%, and even more preferably in the range of 2 to 15 mass%, relative to 100 mass% of the total amount of the dental composition (B). The content of the filler (d) in the dental adhesive composition (A) is not particularly limited, and the dental adhesive composition (A) may not contain the filler (d). In an embodiment in which the dental adhesive composition (A) contains a filler (d), the content of the filler (d) is preferably in the range of 0.1 to 30 mass%, more preferably in the range of 0.5 to 20 mass%, and even more preferably in the range of 1.0 to 10 mass%, relative to 100 mass% of the total amount of the dental adhesive composition (A).

[0118] In the dental composition (B), from the viewpoint of easily adjusting the desired 50% stress relaxation distance and bending displacement, the mass ratio of the content of the (meth)acrylic compound (b-1) to the content of the filler (d) is preferably (b-1):(d)=100:5 to 100:1000, more preferably 100:10 to 100:450, and even more preferably 100:20 to 100:300. When the content of the filler (d) is within the above-mentioned range and the mass ratio of the content of the (meth)acrylic compound (b-1) to the content of the filler (d) is within the above-mentioned range, the cured product does not become too hard, has excellent flexibility, and peeling is easily limited to a certain area.

[0119] <Polymerization accelerator (e)> From the viewpoint of the mechanical strength of the cured product, the dental adhesive composition (A) and the dental composition (B) preferably contain a polymerization accelerator (e) together with at least one of the water-soluble photopolymerization initiator (c-1a), the water-insoluble photopolymerization initiator (c-1b), and the chemical polymerization initiator (c-2). The polymerization accelerator (e) (e.g., amines) contained in the dental adhesive composition (A) and the polymerization accelerator (e) (e.g., amines) contained in the dental composition (B) may be the same or different.

[0120] Examples of the polymerization accelerator (e) used in the present invention include amines, 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.

[0121] The amines used as the polymerization accelerator (e) are divided into aliphatic amines and aromatic amines. Examples of aliphatic amines include primary aliphatic amines such as n-butylamine, n-hexylamine, and n-octylamine; secondary aliphatic amines such as diisopropylamine, dibutylamine, and N-methylethanolamine; and tertiary aliphatic amines such as N-methyldiethanolamine, N-ethyldiethanolamine, Nn-butyldiethanolamine, N-lauryldiethanolamine, 2-(dimethylamino)ethyl methacrylate, N-methyldiethanolamine dimethacrylate, N-ethyldiethanolamine dimethacrylate, triethanolamine monomethacrylate, triethanolamine dimethacrylate, triethanolamine trimethacrylate, triethanolamine, trimethylamine, triethylamine, and tributylamine. Among these, from the viewpoint of the curability and storage stability of the dental adhesive composition (A) and the dental composition (B), tertiary aliphatic amines are preferred, and among these, 2-(dimethylamino)ethyl methacrylate, N-methyldiethanolamine, and triethanolamine are more preferably used. In this specification, the polymerization accelerator (e) containing a polymerizable group, such as 2-(dimethylamino)ethyl methacrylate, is included in 100 parts by mass of the total amount of monomers. Therefore, in the polymerization accelerator (e), a compound having a polymerizable group and also corresponding to a polymerizable monomer (for example, a compound corresponding to a monomer (b) having no acidic group) may be excluded.

[0122] Examples of aromatic amines include N,N-bis(2-hydroxyethyl)-3,5-dimethylaniline, N,N-bis(2-hydroxyethyl)-p-toluidine, 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, and 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, 4-(N,N-dimethylamino)ethyl benzoate, 4-(N,N-dimethylamino)methyl benzoate, 4-(N,N-dimethylamino)propyl benzoate, 4-(N,N-dimethylamino)n-butoxyethyl benzoate, 4-(N,N-dimethylamino)2-(methacryloyloxy)ethyl benzoate, 4-(N,N-dimethylamino)benzophenone, and 4-(N,N-dimethylamino)butyl benzoate. Among these, from the viewpoint of imparting excellent curing properties to the dental adhesive composition (A) and the dental composition (B), at least one selected from the group consisting of N,N-bis(2-hydroxyethyl)-p-toluidine, ethyl 4-(N,N-dimethylamino)benzoate, n-butoxyethyl 4-(N,N-dimethylamino)benzoate, and 4-(N,N-dimethylamino)benzophenone is preferably used.

[0123] 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 include those described in WO 2008 / 087977. Among the polymerization accelerators (e), examples of the thiourea compounds include 1-(2-pyridyl)-2-thiourea, thiourea, methylthiourea, ethylthiourea, N,N'-dimethylthiourea, N,N'-diethylthiourea, N,N'-di-n-propylthiourea, N,N'-dicyclohexylthiourea, trimethylthiourea, triethylthiourea, tri-n-propylthiourea, tricyclohexylthiourea, tetramethylthiourea, tetraethylthiourea, tetra-n-propylthiourea, tetracyclohexylthiourea, 3,3-dimethylethylenethiourea, and 4,4-dimethyl-2-imidazolidinethione. Examples of vanadium compounds include divanadium(IV) tetroxide, vanadyl acetylacetonate(IV), vanadyl oxalate(IV), vanadyl sulfate(IV), oxobis(1-phenyl-1,3-butanedionato)vanadium(IV), bis(maltolato)oxovanadium(IV), vanadium pentoxide(V), sodium metavanadate(V), and ammonium metavanadate(V).

[0124] The polymerization accelerator (e) may be used alone or in combination of two or more kinds. The content of the polymerization accelerator (e) used in the present invention is not particularly limited, but from the viewpoint of the curability of the dental adhesive composition (A) and dental composition (B) obtained, it is preferably 0.001 to 30 parts by mass, more preferably 0.01 to 10 parts by mass, and even more preferably 0.1 to 5 parts by mass, relative to 100 parts by mass of the total amount of monomers in the dental adhesive composition (A) and dental composition (B). When the content of the polymerization accelerator (e) is equal to or more than the lower limit, polymerization proceeds sufficiently and sufficient adhesive strength is easily obtained. On the other hand, when the content of the polymerization accelerator (e) is equal to or less than the upper limit, sufficient adhesiveness is easily obtained, and further, precipitation of the polymerization accelerator (e) itself from the dental adhesive composition (A) and dental composition (B) can be suppressed.

[0125] <Water(f)> The dental adhesive composition (A) of the present invention contains water (f). Water improves adhesion to tooth tissue by demineralizing the surface of the tooth. It is necessary to use water that is substantially free of impurities that adversely affect adhesion, and distilled water or ion-exchanged water is preferable. If the water content is too low, the demineralization promoting effect may not be sufficiently obtained, and if the water content is too high, adhesion may decrease. Therefore, the content of water (f) is preferably in the range of 1 to 50 mass%, more preferably in the range of 2 to 50 mass%, and even more preferably in the range of 3 to 20 mass%, based on the total amount of the dental adhesive composition (A) (100 mass%).

[0126] Organic solvents The dental adhesive composition (A) may further contain an organic solvent. When the dental adhesive composition (A) of the present invention contains an organic solvent, it is possible to further improve adhesion, application property, and penetration into tooth structure, and to further prevent separation of each component of the composition. As the organic solvent, an organic solvent is usually used that has a boiling point of 150°C or less under normal pressure and a solubility in water of 5% by mass or more at 25°C, more preferably 30% by mass or more, and further preferably is soluble in water at any ratio.

[0127] Examples of organic solvents include alcohols such as methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, and 2-methyl-2-propanol; ketones such as acetone and methyl ethyl ketone; ethers such as tetrahydrofuran, diethyl ether, and diisopropyl ether; hydrocarbons such as hexane, toluene, and chloroform; and esters such as ethyl acetate and butyl acetate. Among these, when considering both safety to living organisms and ease of removal based on volatility, it is preferable that the organic solvent is a water-soluble organic solvent, specifically, ethanol, 2-propanol, 2-methyl-2-propanol, acetone, and tetrahydrofuran are preferred, and ethanol, 2-propanol, acetone, 2-methyl-2-propanol, and tetrahydrofuran are more preferred. The content of the organic solvent is not particularly limited, and in some embodiments, the organic solvent does not need to be added. In the embodiment in which the organic solvent is used, the content of the organic solvent is preferably in the range of 1 to 85 mass %, more preferably in the range of 10 to 80 mass %, and even more preferably in the range of 15 to 75 mass %, relative to 100 mass % of the total amount of the dental adhesive composition (A).

[0128] <Fluoride ion releasing substances> The dental adhesive composition (A) and the dental composition (B) may further contain a fluoride ion-releasing substance. By containing the fluoride ion-releasing substance, the dental adhesive composition (A) and the dental composition (B) that can impart acid resistance to tooth structure can be obtained. Examples of fluoride ion releasing substances include fluoride ion releasing polymers such as copolymers of methyl methacrylate and methacrylic acid fluoride; and metal fluorides such as sodium fluoride, potassium fluoride, sodium monofluorophosphate, lithium fluoride, and ytterbium fluoride. The above fluoride ion releasing substances may be used alone or in combination of two or more kinds.

[0129] Furthermore, the dental adhesive composition (A) and the dental composition (B) may contain known additives within limits that do not impair the performance. Examples of the additives include polymerization inhibitors, antioxidants, colorants (pigments, dyes), ultraviolet absorbers, fluorescent agents, solvents such as organic solvents, thickeners, and the like. The additives may be used alone or in combination of two or more kinds. In one embodiment, the content of the solvent (e.g., water, organic solvent) in the dental composition (B) is preferably less than 1 mass%, more preferably less than 0.1 mass%, and even more preferably less than 0.01 mass%, based on the total amount (100 mass) of the dental composition (B).

[0130] From the viewpoint of storage stability and adjustment of curing property, the dental adhesive composition (A) and the dental composition (B) of the present invention preferably contain a polymerization inhibitor. Examples of the polymerization inhibitor include hydroquinone, hydroquinone monomethyl ether, dibutyl hydroquinone, dibutyl hydroquinone monomethyl ether, t-butyl catechol, 2-t-butyl-4,6-dimethylphenol, 2,6-di-t-butylphenol, 3,5-di-t-butyl-4-hydroxytoluene, etc. These may be used alone or in combination of two or more. The content of the polymerization inhibitor is preferably 0.001 to 1.0 part by mass relative to 100 parts by mass of the total amount of the monomers in the dental adhesive composition (A) and the dental composition (B).

[0131] The dental adhesive composition (A) and the dental composition (B) can be easily produced by methods known to those skilled in the art.

[0132] The dental composition (B) of the present invention can be suitably used as a material for fixing loose teeth, a pit and fissure filling material, a bonding material (e.g., orthodontic bonding material, etc.), a temporary dental adhesive, etc., and is particularly suitable for use as a material for fixing loose teeth, since it can limit peeling even for teeth with large mobility to only a small extent and can effectively prevent the hardened material from falling off.

[0133] The dental composition (B) of the present invention is not particularly limited, and may be either a one-component type or a two-component type.

[0134] In the dental adhesive composition kit of the present invention, in addition to the dental adhesive composition (A), the dental composition (B) may be combined with a dental etching material, a dental primer, etc. From the viewpoint of adhesive strength to tooth structure, it is preferable to combine with a dental etching material. In the dental adhesive composition kit of the present invention, a dental primer may be used as the dental adhesive composition (A) and combined with the dental composition (B). In one preferred embodiment, the dental adhesive composition (A) is a dental bonding material, and the dental adhesive composition kit can be mentioned. When the dental adhesive composition (A) is a dental bonding material, the dental adhesive composition (A) may contain a hydrophobic monomer (b-2) that does not have an acidic group (e.g., a bifunctional hydrophobic monomer of an aromatic compound). Certain other suitable embodiments include a dental adhesive composition kit, in which the dental adhesive composition (A) is a dental primer.

[0135] As a dental adhesive composition kit, it is particularly suitable for use as a kit for fixing loose teeth, since it can limit peeling to only a portion of the tooth even when the tooth is significantly mobile, and can effectively prevent the hardened product from falling off.

[0136] <Specific application methods and procedures> A method for applying the dental adhesive composition kit will be described below by taking as an example an embodiment in which the dental adhesive composition kit of the present invention is combined with a dental etching material. A dental etching material is applied to the tooth surface to which the dental composition (B) is to be applied. After application, the tooth surface is washed with water and dried. Next, the dental adhesive composition (A) is applied. After volatilizing the water and solvent with an air blower, if the dental adhesive composition (A) contains a photopolymerization initiator, it is irradiated with light using a dental light irradiator to harden it. After filling with the dental composition (B) and preparing the surface, if the dental composition (B) contains a photopolymerization initiator, it is irradiated with light using a dental light irradiator to harden it. In some cases, the surface shape is corrected and polished. When the dental composition (B) of the present invention and a dental adhesive composition kit containing the dental composition (B) are used to fix a tooth that is highly mobile, the dental composition (B) has a paste-like consistency that allows it to be applied directly between the teeth, and the dental composition (B) and the dental adhesive composition kit containing the dental composition (B) are also easy to use. EXAMPLES

[0137] The present invention will be described in detail below with reference to examples and comparative examples, but the present invention is not limited to the examples. In the examples, the parts are by weight unless otherwise specified.

[0138] Next, the components of the dental adhesive composition (A) and the dental composition (B) of the Examples and Comparative Examples are shown below together with their abbreviations.

[0139] [Monomer (a) having an acidic group] MDP: 10-methacryloyloxydecyl dihydrogen phosphate

[0140] [Monomer (b) having no acidic group] D-2.6E: 2,2-bis(4-methacryloyloxypolyethoxyphenyl)propane (average number of moles of ethoxy groups added: 2.6) Bis-GMA: 2,2-bis[4-(2-hydroxy-3-methacryloyloxypropoxy)phenyl]propane UDMA: [2,2,4-trimethylhexamethylenebis(2-carbamoyloxyethyl)]dimethacrylate 3G: Triethylene glycol dimethacrylate DD: 1,10-decanediol dimethacrylate DEAA: N,N-diethylacrylamide MAEA: N-methacryloyloxyethyl acrylamide HEMA: 2-hydroxyethyl methacrylate POB-MA: Phenoxybenzyl methacrylate DMAEMA: 2-(Dimethylamino)ethyl methacrylate #801: 1,2-bis(3-methacryloyloxy-2-hydroxypropoxy)ethane UN-7700: Urethane acrylate (manufactured by Negami Chemical Industries, Ltd., weight average molecular weight (Mw): 15,000 to 25,000, glass transition temperature (Tg): -41°C, polyester skeleton, number of polymerizable groups: 2, weight average molecular weight per acrylic group: 7,500 to 12,500) UN-7600: Urethane acrylate (manufactured by Negami Chemical Industrial Co., Ltd., weight average molecular weight (Mw): 11,500, glass transition temperature (Tg): -42°C and 44.6°C, number of polymerizable groups: 2, weight average molecular weight per acrylic group: 5,750) The weight average molecular weight (Mw) refers to the weight average molecular weight calculated in terms of polystyrene as determined by gel permeation chromatography (GPC).

[0141] Production of acrylic block copolymers The acrylic block copolymer was produced according to the method described in JP 2012-046468 A. (1) A 1-liter three-neck flask was fitted with a three-way cock, the inside of which was degassed and replaced with nitrogen. Then, at room temperature, 390 g of toluene, 1.4 ml of N,N',N',N'',N''-pentamethyldiethylenetriamine, and 18 ml of a toluene solution containing 11 mmol of isobutylbis(2,6-di-t-butyl-4-methylphenoxy)aluminum were added, and 1.7 ml of a mixed solution of cyclohexane and n-hexane containing 2.2 mmol of sec-butyllithium were added. 35 ml of methyl methacrylate was added to this, and the reaction was carried out at room temperature for 1 hour. At this point, 1 g of the reaction liquid was collected and used as the sampling sample 1. Subsequently, the internal temperature of the polymerization liquid was cooled to -15°C, and 75 ml of n-butyl acrylate was added dropwise over 5 hours. After the dropwise addition was completed, 1 g of the reaction solution was collected and used as sampling sample 2. Then, 35 ml of methyl methacrylate was added, and the reaction solution was warmed to room temperature and stirred for about 10 hours. 1 g of methanol was added to the reaction solution to terminate the polymerization. The reaction solution after the polymerization was terminated was poured into a large amount of a mixed solution of methanol and water (methanol 90% by mass), and the white precipitate that precipitated was collected and used as sampling sample 3.

[0142] (2) The samples 1 to 3 collected or recovered in (1) above are subjected to GPC measurement by the method described above. 1 H-NMR measurement was performed, and based on the results, the Mw, Mw / Mn, and mass ratio of the methyl methacrylate polymer (PMMA) block and the n-butyl acrylate polymer (PnBA) block of the polymers and block copolymers obtained at each polymerization stage were calculated. It was found that the white precipitate finally obtained in (1) above was a triblock copolymer consisting of PMMA-PnBA-PMMA, with an overall Mw of 85,000, an Mw / Mn of 1.03, and a ratio of each polymer block being PMMA (25% by mass)-PnBA (50% by mass)-PMMA (25% by mass) (total of 50% by mass of PMMA). Sample 1 was PMMA with an Mw of 18,000 and an Mw / Mn of 1.05; Sample 2 was a PMMA-PnBA diblock copolymer with an Mw of 67,000 and an Mw / Mn of 1.14.

[0143] [Photopolymerization initiator (c-1)] CQ: Camphorquinone BAPO: Bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide Li-TPO: Lithium phenyl(2,4,6-trimethylbenzoyl)phosphinate [Chemical polymerization initiator (c-2)] THP: 1,1,3,3-tetramethylbutyl hydroperoxide

[0144] Filler (d) Inorganic filler 1: Silane-treated silica 100 g of Ar130 (manufactured by Nippon Aerosil Co., Ltd., hydrophilic fumed silica, ultrafine silica "Aerosil (registered trademark) 130", average particle size: 16 nm, refractive index: 1.46), 30 g of γ-methacryloyloxypropyltrimethoxysilane, and 200 mL of 0.3 mass% acetic acid aqueous solution were placed in a three-neck flask and stirred for 2 hours under ultrasonic dispersion at room temperature. After removing water by freeze-drying, the mixture was heated at 90°C for 3 hours to obtain inorganic filler 1. Inorganic filler 2: Silane-treated silica powder (quartz) Silica powder (manufactured by Nichitsu Co., Ltd., product name: High Silica, refractive index: 1.55) was pulverized with a dry ball mill (Φ10mm alumina balls) to obtain pulverized silica powder. The average particle size of the obtained pulverized silica powder was measured on a volume basis using a laser diffraction particle size distribution measuring device (manufactured by Shimadzu Corporation, model "SALD-2300") and was found to be 2.2 μm. 100 g of this pulverized silica powder, 4 parts by mass of γ-methacryloyloxypropyltrimethoxysilane (4 g) by a conventional method, and 200 mL of an aqueous acetic acid solution were placed in a three-neck flask and stirred for 2 hours under ultrasonic dispersion at room temperature. After removing water by freeze-drying, the mixture was heated at 90°C for 3 hours to obtain inorganic filler 2. R972: Hydrophobic fumed silica, ultrafine silica "Aerosil (registered trademark) R972", manufactured by Nippon Aerosil Co., Ltd., average particle size: 16 nm (silica), refractive index: 1.46 Ar380: Nippon Aerosil Co., Ltd., ultrafine silica "Aerosil 380", average particle size: 7 nm

[0145] [Polymerization accelerator (e)] DABE: Ethyl 4-(N,N-dimethylamino)benzoate DEPT: N,N-bis(2-hydroxyethyl)-p-toluidine DMETU: 4,4-Dimethyl-2-imidazolidinethiol VOAA: Vanadyl acetylacetonate(IV)

[0146] [others] BHT: 3,5-di-t-butyl-4-hydroxytoluene (polymerization inhibitor)

[0147] [Examples 1 to 9 and Comparative Examples 1 to 5] [Preparation of dental adhesive composition (A) and dental composition (B)] The components shown in Table 1 were mixed at room temperature (23° C.) to prepare a liquid dental adhesive composition (A). A paste-like dental composition (B) was prepared by mixing and kneading each component other than the dental adhesive composition (A) shown in Table 2 in a dark place at room temperature (23°C) to make a homogeneous mixture and degassing it under vacuum. For Example 8, the dental composition (B) was a paste obtained by kneading paste A and paste B in Table 2 for 10 seconds or more on a mixing paper prepared separately immediately before the test.

[0148] Test Example 1 Shear bond strength (enamel after phosphoric acid etching) The test was conducted in accordance with ISO29022:2013. Specifically, the test is as follows: The labial surfaces of bovine teeth were polished with #80 silicon carbide paper (Nihon Kenshi Co., Ltd.) under running water to obtain samples with exposed flat surfaces of enamel. First, the shear bond strength to enamel was measured using a sample with the flat surface of the enamel exposed, using the following method. Tape was applied to the bottom surface of a separately prepared mold having 15 holes (15-hole mold, manufactured by Ultradent, φ35 mm×height 25 mm), and the sample bovine tooth was fixed onto the tape. Next, a resin for dental impression trays (trade name "Tray Resin II", manufactured by Matsufu Co., Ltd.) was filled into the mold and left to stand for about 30 minutes to harden the resin for dental impression trays, thereby obtaining a composite of bovine teeth and hardened resin. The composite was taken out of the mold as a sample. The composite was in a state where the bovine tooth was exposed on the upper surface of the hardened resin. The upper surface of the sample was polished under running water with #600 silicon carbide paper (manufactured by Nihon Kenshi Co., Ltd.) until the size of the surface to be adhered (φ2.38 mm or more) was secured, and the surface to be adhered was washed with ultrasonic waves for 5 minutes.

[0149] Next, a phosphoric acid etching agent (product name "K Etchant Syringe", manufactured by Kuraray Noritake Dental Co., Ltd.) (a separately prepared φ2.38 mm CR filling mold (Bonding Mold Insert, manufactured by Ultradent Japan Co., Ltd.)) was applied to the enamel surface, which was the adhesion surface, and left for 10 seconds. After that, it was washed with water and the enamel surface was dried. Next, for the examples and comparative examples (Examples 1 to 8 and Comparative Examples 2 to 5) in which the dental adhesive composition (A) was applied, the dental adhesive composition (A) was applied to the area where the phosphoric acid etching agent had been applied, and after leaving it for 10 seconds, mild air was blown for 5 seconds or more to volatilize the solvent. Example 9 and Comparative Example 1 were conducted in the same manner as Example 1, except that the dental adhesive composition (A) was not applied to the area where the phosphoric acid etching material was applied.

[0150] After volatilization, the dental adhesive composition (A) was cured by irradiating it with light for 10 seconds using a dental LED light irradiator (product name "VALO", manufactured by Ultradent Japan Co., Ltd.). Next, a dedicated tool (Bonding Clamp, manufactured by Ultradent Japan Co., Ltd.) was attached, and the CR filling mold attached to the dedicated tool was lowered so that the CR filling mold was in close contact with the adhesion surface of the sample, and the sample was fixed in place. Next, the prepared dental composition (B) was thinly filled into the hole of the CR filling mold to a thickness of 1 mm or less. After that, the dental composition (B) was filled into the CR filling mold again (up to about 2 / 3 of the mold, about 2 mm thick), and left for 10 seconds, and then irradiated with light for 10 seconds with a dental LED light irradiator (product name "VALO", manufactured by Ultradent Japan Co., Ltd.) to harden the dental composition (B) and obtain a hardened product. The cured product was removed from the CR filling mold to prepare a test sample for the adhesion test. Ten test samples for the adhesion test were prepared.

[0151] The resulting cured product was placed in a container filled with distilled water immediately after curing. The five adhesive test samples were immersed in distilled water in a container, and the container was left in an incubator set at 37°C for 15 minutes. Immediately after removing from the distilled water, the shear adhesive strength to enamel was measured. The average value of the measurement results is shown in Table 2 as "immediately after curing." The remaining adhesion test samples were immersed in distilled water in a container and the container was left in an incubator set at 37°C for 24 hours, and the shear bond strength to enamel was measured immediately after removing from the distilled water. The average value of the measurement results is shown in Table 2 as "37°C 24 hours later." The adhesive strength (shear adhesive strength) was measured by attaching the adhesive test sample to a dedicated holder (Test Base Clamp, manufactured by Ultradent Japan Co., Ltd.) and using a dedicated tool (Crosshead Assembly, manufactured by Ultradent Japan Co., Ltd.) and a universal testing machine (manufactured by Shimadzu Corporation) with the crosshead speed set to 1 mm / min. The average values ​​are shown in the table (n=5). During the measurement, the 50% stress relaxation distance was calculated from the displacement at the time of maximum stress and the displacement at the time when the stress became 50% after reaching the maximum stress.

[0152] From the viewpoint of adhesion to tooth structure, the higher the shear bond strength to enamel, the better, and immediately after application, it is preferably 10 MPa or more, more preferably 12 Pa or more, and even more preferably 15 MPa or more. After 24 hours at 37°C, the shear bond strength to enamel is preferably 18 MPa or more, more preferably 20 MPa or more, and even more preferably 23 MPa or more. From the viewpoint of fixing loose teeth, the higher the 50% stress relaxation distance, the more preferable. Both "immediately after hardening" and "after 24 hours at 37°C", the distance is preferably 0.008 mm or more, more preferably 0.010 mm or more, and even more preferably 0.040 mm or more.

[0153] Test Example 2: Bending properties (bending strength, bending displacement) The bending strength and bending displacement were evaluated by bending tests in accordance with ISO 4049:2019. Specifically, the bending strength and bending displacement were evaluated as follows. The dental composition (B) thus prepared was filled into a SUS mold (length 2 mm × width 25 mm × thickness 2 mm), and the top and bottom of the paste (2 mm × 25 mm surfaces) were pressed with a glass slide. Next, in the pressed state, a dental visible light irradiator (trade name "Pencure 2000", manufactured by Morita Corporation) was used to irradiate the paste from above, below, and on the front and back of the paste through the glass slide in standard mode for 10 seconds each at five separate locations on each side (a total of 50 seconds of light irradiation on each side), thereby hardening the paste and obtaining a hardened product. Ten hardened products were prepared for each Example and Comparative Example. Five of the pieces were left in a container immersed in distilled water in an incubator set at 37°C for 15 minutes, after which the three-point bending strength and bending modulus were measured (n=5) using a universal testing machine (Autograph AG-I 100kN, Shimadzu Corporation) with a support distance of 20mm and a crosshead speed of 1mm / min, and the average values ​​were calculated. The average value of the measurement results is shown in Table 2 as "immediately after curing." The remaining five pieces were left in a container immersed in distilled water in an incubator set at 37°C for 24 hours, after which the three-point bending strength and bending displacement were measured (n=5) using a universal testing machine (Autograph AG-I 100kN, manufactured by Shimadzu Corporation) with a support distance of 20mm and a crosshead speed of 1mm / min, and the average values ​​were calculated. The average values ​​of the measurement results are shown in Table 2 as "After 24 hours at 37°C." The bending displacement is the displacement from the moment stress begins to be applied to the test piece until the test piece breaks, and the larger the displacement, the more flexible the material.

[0154] The bending strength (immediately after curing) is preferably 20 MPa or more, more preferably 30 MPa or more, and even more preferably 40 MPa or more, from the viewpoint of the mechanical strength of the cured product. Similarly, from the viewpoint of mechanical strength, the bending strength (after 24 hours at 37° C.) is preferably 10 MPa or more, more preferably 20 MPa or more, and even more preferably 30 MPa or more. The bending displacement, both "immediately after hardening" and "after 24 hours at 37°C", is preferably 3.0 mm or more, more preferably 3.5 mm or more, and even more preferably 4.0 mm or more, from the viewpoint of fixing mobile teeth.

[0155] [Table 1]

[0156] [Table 2]

[0157] As shown in Table 2, the dental compositions of the examples had a shear bond strength immediately after hardening of 10 MPa or more, a 50% stress relaxation distance of 0.008 mm or more, a bending strength of 26 MPa or more, and a bending displacement of 3.1 mm or more. In addition, the dental compositions of the examples had a shear bond strength of 12 MPa or more after 24 hours at 37°C, a 50% stress relaxation distance of 0.008 mm or more, a bending strength of 15 MPa or more, and a bending displacement of 3.2 mm or more. In this way, since the dental composition of the present invention has a high 50% stress relaxation distance value, when the maximum stress is reached, the cured product does not peel off completely, but only partially, and therefore can effectively prevent the cured product from falling off. In addition, since the dental composition of the present invention has a high bending displacement, the cured product has flexibility and can deform when a force is applied to it, thereby mitigating the force, thereby more effectively preventing the cured product from falling off.

[0158] On the other hand, among the comparative examples, the 50% stress relaxation distance was small at 0.007 mm or less and the bending displacement was small at 2.4 mm or less in all of Comparative Examples 1 to 3 and 5. In Comparative Example 4, the bending displacement was small at 1.2 mm or less. It is presumed that the brittleness of the cured product due to the large amount of filler is the cause of the influence in Comparative Examples 1 and 4. It is presumed that the appropriate crosslinking density could not be formed in Comparative Examples 2 (corresponding to Patent Document 2), 3, and 5 because they did not contain the (meth)acrylic compound (b-1) having a weight average molecular weight per (meth)acrylic group of 2,000 or more and less than 20,000. [Industrial Applicability]

[0159] The dental composition and dental adhesive composition kit of the present invention can be suitably used for fixing loose teeth, sealing pits and fissures, orthodontic treatment, and temporary attachment in dental treatment.

Claims

1. It comprises a monomer (b) that does not have an acidic group, a polymerization initiator (c), and a filler (d), Monomer (b) without acidic groups contains (meth)acrylic compound (b-1) having a weight-average molecular weight of 2,000 or more and less than 20,000 per (meth)acrylic group. A dental composition (B) having a filler (d) content of 0.1 to 40% by mass.

2. The dental composition (B) according to claim 1, further comprising a monomer (a) having an acidic group.

3. The dental composition (B) according to claim 1, wherein the (meth)acrylic compound (b-1) comprises a urethane-modified (meth)acrylic compound (b-1a).

4. The dental composition (B) according to claim 1, wherein the content of the (meth)acrylic compound (b-1) is 1 to 70 parts by mass per 100 parts by mass of the total amount of monomers.

5. The dental composition (B) according to claim 1, wherein at least one glass transition temperature (Tg) of the (meth)acrylic compound (b-1) is less than 40°C.

6. The dental composition (B) according to claim 3, wherein the urethane-modified (meth)acrylic compound (b-1a) is a (meth)acrylate having a structure and urethane bond selected from the group consisting of polyester, polycarbonate, polyurethane, polyether, polyconjugated diene, and hydrogenated polyconjugated diene.

7. The dental composition (B) according to claim 1, wherein the dental composition (B) is a single dosage form.

8. The dental composition (B) according to claim 1, wherein the dental composition (B) is in two formulations.

9. The dental composition (B) according to any one of claims 1 to 8, wherein the dental composition (B) is a tooth-fixing material.

10. The dental composition (B) according to any one of claims 1 to 8, wherein the dental composition (B) is a pit and fissure filling material.

11. The dental composition (B) according to any one of claims 1 to 8, wherein the dental composition (B) is an orthodontic bonding material.

12. The dental composition (B) according to any one of claims 1 to 8, wherein the dental composition (B) is a dental temporary adhesive.

13. A dental composition (B) according to any one of claims 1 to 8 and a dental adhesive composition (A) A dental adhesive composition kit comprising a dental adhesive composition (A) containing an acidic monomer (a), a non-acidic monomer (b), a polymerization initiator (c) and / or a polymerization accelerator (e), and water (f).

14. The dental adhesive composition kit according to claim 13, wherein the 50% stress relaxation distance when measuring the shear adhesive strength immediately after curing is 0.010 mm or more.

15. The dental adhesive composition kit according to claim 13, wherein the dental adhesive composition (A) is a dental bonding material.

16. The dental adhesive composition kit according to claim 13, wherein the dental adhesive composition (A) is a dental primer.