Dental composition and dental restoration kit

Abstract

One aspect of the present invention pertains to a one-agent-type dental composition containing a (meth)acrylate, a photopolymerization initiator, a thiourea derivative, a water-soluble organic solvent, and water, wherein the photopolymerization initiator contains a diallyl iodonium salt.

Description

[Technical Field]

[0001] The present invention relates to dental compositions and kits for dental restoration. [Background technology]

[0002] When repairing a prosthesis by bonding it to a tooth surface with resin cement, the adhesiveness of the resin can be improved by applying a primer to the tooth surface or the prosthesis in advance (see, for example, Patent Documents 1 and 2).

[0003] On the other hand, when a composite resin is directly filled into a cavity for repair, the adhesiveness of the resin can be improved by applying a bonding material to the cavity in advance (see, for example, Patent Document 3). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-280630 [Patent Document 2] International Publication No. 2013 / 046648 [Patent Document 3] Japanese Patent Application Laid-Open No. 2003-73218 Summary of the Invention [Problem to be solved by the invention]

[0005] However, there is a demand for a one-component dental composition that can achieve both the adhesiveness and storage stability of the resin whether it is applied as a primer or a bonding material.

[0006] One aspect of the present invention aims to provide a one-component dental composition that can achieve both resin adhesion and storage stability regardless of whether it is applied as a primer or a bonding material. [Means for solving the problem]

[0007] One aspect of the present invention is a one-component dental composition, which contains a (meth)acrylate, a photopolymerization initiator, a thiourea derivative, a water-soluble organic solvent, and water, and a vanadium compound. Contains First, the photopolymerization initiator includes diphenyliodonium hexafluorophosphate or bis(4-tert-butylphenyl)iodonium hexafluorophosphate, before The content of the photopolymerization initiator is 0.5 to 5 mass %. and the thiourea derivative is a compound selected from ethylene thiourea, N-methyl thiourea, N-ethyl thiourea, N-propyl thiourea, N-butyl thiourea, N-lauryl thiourea, N-phenyl thiourea, N-cyclohexyl thiourea, N,N-dimethyl thiourea, N,N-diethyl thiourea, N,N-dipropyl thiourea, N,N-dibutyl thiourea, N,N-dilauryl thiourea, N,N-diphenyl thiourea, N,N-dicyclohexyl thiourea, trimethyl thiourea, tetramethyl thiourea, N-acetyl thiourea, N-benzoyl thiourea, 1-allyl-3-(2-hydroxyethyl)-2-thiourea, 1-(2-tetrahydrofurfuryl)-2-thiourea, N-tert-butyl-N'-isopropyl thiourea, and 2-pyridyl thiourea. . [Effects of the Invention]

[0008] According to one aspect of the present invention, a one-component dental composition can be provided that can achieve both resin adhesion and storage stability, whether applied as a primer or a bonding material. DETAILED DESCRIPTION OF THE INVENTION

[0009] Next, an embodiment of the present invention will be described.

[0010] <Dental composition> The dental composition of this embodiment is a one-component dental composition.

[0011] The dental composition of the present embodiment contains a (meth)acrylate, a photopolymerization initiator, a thiourea derivative, a water-soluble organic solvent, and water.

[0012] The dental composition of this embodiment can be used as, for example, a primer, a bonding material, and the like.

[0013] The components constituting the dental composition of this embodiment will be described below.

[0014] <(Meth)acrylate> In the present specification and claims, the term "(meth)acrylate" refers to a compound (e.g., a monomer, oligomer, or prepolymer) having one or more (meth)acryloyloxy groups, and the term "(meth)acryloyloxy group" refers to a methacryloyloxy group and / or an acryloyloxy group.

[0015] Although the (meth)acrylate may or may not have an acid group, the dental composition of the present embodiment preferably contains both a (meth)acrylate with an acid group and a (meth)acrylate without an acid group, which further improves the adhesiveness of resins when the dental composition of the present embodiment is used as a primer or bonding material.

[0016] Examples of (meth)acrylates having an acid group that can be used include (meth)acrylates having a phosphoric acid group, (meth)acrylates having a pyrophosphate group, (meth)acrylates having a thiophosphate group, (meth)acrylates having a carboxyl group, (meth)acrylates having a sulfonic acid group, and (meth)acrylates having a phosphonic acid group.

[0017] The (meth)acrylate having an acid group may have a plurality of acid groups.

[0018] In addition, instead of a (meth)acrylate having an acid group, an acid anhydride, an acid chloride, an alkali metal salt, an amine salt (ammonium salt), or the like of a (meth)acrylate having an acid group may be used.

[0019] Because a phosphate group or a thiophosphate group exhibits stronger acidity than a carboxyl group, the dental composition of this embodiment preferably contains a (meth)acrylate having a phosphate group or a thiophosphate group, which improves the tooth demineralization properties of the dental composition of this embodiment, thereby further improving the adhesiveness of resins when the dental composition of this embodiment is used as a primer or bonding material.

[0020] Examples of (meth)acrylates having a phosphate group include 2-(meth)acryloyloxyethyl dihydrogen phosphate, bis[2-(meth)acryloyloxyethyl]hydrogen phosphate, 2-(meth)acryloyloxyethylphenyl hydrogen phosphate, 6-(meth)acryloyloxyhexyl dihydrogen phosphate, 6-(meth)acryloyloxyhexylphenyl hydrogen phosphate, 10-(meth)acryloyloxydecyl dihydrogen phosphate, 1,3-di(meth)acryloylpropane-2-dihydrogen phosphate, 1,3-di(meth)acryloylpropane-2-phenyl hydrogen phosphate, and bis[5-{2-(meth)acryloyloxyethoxycarbonyl}heptyl]hydrogen phosphate.

[0021] Examples of (meth)acrylates 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, and bis[10-(meth)acryloyloxydecyl] pyrophosphate.

[0022] Examples of the (meth)acrylate having a thiophosphate group include 2-(meth)acryloyloxyethyl dihydrogenthiophosphate, 3-(meth)acryloyloxypropyl dihydrogenthiophosphate, 4-(meth)acryloyloxybutyl dihydrogenthiophosphate, 5-(meth)acryloyloxypentyl dihydrogenthiophosphate, 6-(meth)acryloyloxyhexyl dihydrogenthiophosphate, 7-(meth)acryloyloxyheptyl dihydrogenthiophosphate, 8-(meth)acryloyloxyoctyl dihydrogenthiophosphate, 9-(meth)acryloyloxynonyl dihydrogenthiophosphate, 10-(meth)acryloyloxydecyl dihydrogenthiophosphate, and 11-(meth)acryloyloxyundecyl. Examples of the acryloyloxyisopropyl acrylate include 1-(meth)acryloyloxyisopropyl acrylate, ...

[0023] Examples of (meth)acrylates having a carboxyl group include 4-(meth)acryloyloxyethyltrimellitic acid, 4-(meth)acryloyloxydecyltrimellitic acid, 11-(meth)acryloyloxy-1,1-undecanedicarboxylic acid, 1,4-di(meth)acryloyloxypyromellitic acid, 2-(meth)acryloyloxyethyl maleic acid, 2-(meth)acryloyloxyethyl phthalic acid, and 2-(meth)acryloyloxyethylhexahydrophthalic acid.

[0024] Examples of the (meth)acrylate having a sulfonic acid group include 2-(meth)acrylamido-2-methylpropanesulfonic acid, styrenesulfonic acid, and 2-sulfoethyl(meth)acrylate.

[0025] Examples of the (meth)acrylate 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-3-phosphonoacetate, and 10-(meth)acryloyloxydecyl-3-phosphonoacetate.

[0026] The (meth)acrylates having an acid group may be used alone or in combination of two or more kinds.

[0027] The content of the (meth)acrylate having an acid group in the dental composition of this embodiment is preferably 1 to 60% by mass, and more preferably 5 to 30% by mass. When the content of the (meth)acrylate having an acid group in the dental composition of this embodiment is 1% by mass or more, the adhesiveness of the resin when the dental composition of this embodiment is used as a primer or bonding material is further improved, and when the content is 60% by mass or less, the storage stability of the dental composition of this embodiment is further improved.

[0028] Examples of (meth)acrylates having no acid group include methyl (meth)acrylate, ethyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, hydroxypropyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, glycidyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-methoxyethyl (meth)acrylate, 2-methyl-2-propanol ... (meth)acrylate, 2-ethoxyethyl (meth)acrylate, 2-methylhexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, benzyl (meth)acrylate, 2-hydroxy-1,3-di(meth)acryloyloxypropane, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, butylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 1,3-butanediol Di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, trimethylolethane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, trimethylolmethane tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, polybutylene glycol di(meth)acrylate, bisphenol A diglycidyl (meth)acrylate, di-2-(meth)acrylate Acryloyloxyethyl-2,2,4-trimethylhexamethylene dicarbamate, 1,3,5-tris[1,3-bis{(meth)acryloyloxy}-2-propoxycarbonylaminohexane]-1,3,5-(1H,3H,5H)triazine-2,4,6-trione, 2,2-bis[4-(3-(meth)acryloyloxy-2-hydroxypropyl)phenyl]propane, N,N'-(2,2,4-trimethylhexamethylene)bis[2-(aminocarboxy)propane-1,3-diol]tetramethacrylate, 2,Examples include a (meth)acrylate of a urethane oligomer composed of 2'-bis(4-hydroxycyclohexyl)propane, 2-oxypanone, hexamethylene diisocyanate, and 2-hydroxyethyl (meth)acrylate, and a (meth)acrylate of a urethane oligomer composed of 1,3-butanediol, hexamethylene diisocyanate, and 2-hydroxyethyl (meth)acrylate, and two or more of these may be used in combination.

[0029] The content of the (meth)acrylate having no acid group in the dental composition of this embodiment is preferably 0.5 to 65 mass %, more preferably 10 to 35 mass %. When the content of the (meth)acrylate having no acid group in the dental composition of this embodiment is 0.5 mass % or more and 65 mass % or less, the adhesiveness of resin is further improved when the dental composition of this embodiment is used as a primer and a bonding material.

[0030] <Photopolymerization initiator> The photopolymerization initiator includes a diaryliodonium salt.

[0031] Examples of diaryliodonium salts include diphenyliodonium hexafluorophosphate, bis(4-tert-butylphenyl)iodonium hexafluorophosphate, and the like.

[0032] Other diaryliodonium compounds that can be used to form diaryliodonium salts include diphenyliodonium, bis(p-chlorophenyl)iodonium, ditolyliodonium, bis(p-tert-butylphenyl)iodonium, p-isopropylphenyl-p-methylphenyliodonium, bis(m-nitrophenyl)iodonium, (p-tert-butylphenyl)phenyliodonium, (p-methoxyphenyl)phenyliodonium, bis(p-methoxyphenyl)iodonium, bis(pyridine)iodonium, (p-octyloxyphenyl)phenyliodonium, and (p-phenoxyphenyl)phenyliodonium.

[0033] Counter ions of the diaryliodonium include chloride, bromide, p-toluenesulfonate, trifluoromethanesulfonate, tetrafluoroborate, tetrakispentafluorophenylborate, tetrakispentafluorophenylgallate, hexafluorophosphate, hexafluoroarsenate, and hexafluoroantimonate.

[0034] Among these, diphenyliodonium hexafluorophosphate and bis(4-tert-butylphenyl)iodonium hexafluorophosphate are preferred in terms of the adhesiveness of the resin when the dental composition of this embodiment is used as a bonding material.

[0035] The content of the diaryl iodonium salt in the dental composition of this embodiment is preferably 0.1 to 5 mass %, more preferably 0.1 to 3 mass %. When the content of the diaryl iodonium salt in the dental composition of this embodiment is 0.1 mass % or more, the adhesiveness of the resin when the dental composition of this embodiment is used as a bonding material is further improved, and when the content is 5 mass % or less, the storage stability of the dental composition of this embodiment is further improved.

[0036] The photopolymerization initiator may further include a photopolymerization initiator other than the diaryliodonium salt.

[0037] Examples of photopolymerization initiators other than diaryliodonium salts include camphorquinone, phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, benzil ketal, diacetyl ketal, benzil dimethyl ketal, benzil diethyl ketal, benzil bis(2-methoxyethyl) ketal, 4,4'-dimethyl(benzyl dimethyl ketal), anthraquinone, 1-chloroanthraquinone, 2-chloroanthraquinone, 1,2-benzanthraquinone, 1-hydroxyanthraquinone, 1-methylanthraquinone, 2-ethylanthraquinone, and 1-bromoanthraquinone. Examples of suitable thioxanthone include quinone, thioxanthone, 2-isopropylthioxanthone, 2-nitrothioxanthone, 2-methylthioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2,4-diisopropylthioxanthone, 2-chloro-7-trifluoromethylthioxanthone, thioxanthone-10,10-dioxide, thioxanthone-10-oxide, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzophenone, bis(4-dimethylaminophenyl)ketone, and 4,4'-bis(diethylamino)benzophenone. Among these, camphorquinone and 2,4,6-trimethylbenzoyldiphenylphosphine oxide are preferred in terms of resin adhesion when the dental composition of the present embodiment is used as a bonding material.

[0038] The content of the photopolymerization initiator other than the diaryl iodonium salt in the dental composition of this embodiment is preferably 0.1 to 4 mass%, more preferably 0.5 to 3.5 mass%. When the content of the photopolymerization initiator other than the diaryl iodonium salt in the dental composition of this embodiment is 0.1 mass% or more, the adhesiveness of the resin when the dental composition of this embodiment is used as a bonding material is further improved, and when the content is 4 mass% or less, the storage stability of the dental composition of this embodiment is improved.

[0039] <Thiourea derivatives> The thiourea derivative functions as a reducing agent for the chemical polymerization initiator.

[0040] Examples of thiourea derivatives include ethylene thiourea, N-methyl thiourea, N-ethyl thiourea, N-propyl thiourea, N-butyl thiourea, N-lauryl thiourea, N-phenyl thiourea, N-cyclohexyl thiourea, N,N-dimethyl thiourea, N,N-diethyl thiourea, N,N-dipropyl thiourea, N,N-dibutyl thiourea, N,N-dilauryl thiourea, N,N-diphenyl thiourea, N,N-dicyclohexyl thiourea, trimethyl thiourea, tetramethyl thiourea, N-acetyl thiourea, N-benzoyl thiourea, 1-allyl-3-(2-hydroxyethyl)-2-thiourea, 1-(2-tetrahydrofurfuryl)-2-thiourea, N-tert-butyl-N'-isopropyl thiourea, and 2-pyridyl thiourea, and two or more of these may be used in combination. Among these, N-acetylthiourea and N-benzoylthiourea are preferred in terms of resin adhesion when the dental composition of the present embodiment is used as a primer.

[0041] The content of the thiourea derivative in the dental composition of this embodiment is preferably 0.1 to 5% by mass, more preferably 1 to 2% by mass. When the content of the thiourea derivative in the dental composition of this embodiment is 0.1% by mass or more, the adhesiveness of resin when the dental composition of this embodiment is used as a primer is further improved, and when the content is 5% by mass or less, the storage stability of the dental composition of this embodiment is further improved.

[0042] <Solvent> Examples of water-soluble organic solvents include acetone, methanol, ethanol, isopropyl alcohol, methyl ethyl ketone, etc., and two or more of these may be used in combination. Among these, acetone and ethanol are preferred because of their high biological safety.

[0043] The water content in the dental composition of this embodiment is preferably 4 to 30% by mass, more preferably 5 to 15% by mass. When the water content in the dental composition of this embodiment is 4% by mass or more, the storage stability of the dental composition of this embodiment is further improved, and when the water content is 30% by mass or less, the adhesiveness of resin when the dental composition of this embodiment is used as a primer is further improved.

[0044] The mass ratio of the water-soluble organic solvent to water in the dental composition of this embodiment is preferably 1.3 or more, and more preferably 1.8 or more. When the mass ratio of the water-soluble organic solvent to water in the dental composition of this embodiment is 1.3 or more, the adhesiveness of the resin is further improved when the dental composition of this embodiment is used as a primer.

[0045] The mass ratio of the water-soluble organic solvent to water in the dental composition of this embodiment is usually 10 or less.

[0046] <Other ingredients> The dental composition of this embodiment preferably does not substantially contain a vanadium compound, which further improves the storage stability of the dental composition of this embodiment.

[0047] The content of the vanadium compound in the dental composition of this embodiment is preferably 0.01% by mass or less, and more preferably 0.005% by mass or less.

[0048] The vanadium compound functions as a reducing agent for the chemical polymerization initiator.

[0049] Examples of vanadium compounds include oxovanadium oxalate, vanadyl acetylacetonate, vanadium acetylacetonate, vanadyl stearate, vanadium naphthenate, and vanadium benzoylacetonate.

[0050] The dental composition of the present embodiment may further contain a filler, a tertiary amine, a polymerization inhibitor, and the like.

[0051] Examples of the filler include silicic acid anhydride powder, fumed silica, alumina powder, barium glass powder, and fluoroaluminosilicate glass powder, and two or more of these may be used in combination.

[0052] The filler may be treated with a surface treatment agent such as a silane coupling agent.

[0053] The tertiary amine functions as a reducing agent for the chemical polymerization initiator.

[0054] The tertiary amine may be either a tertiary aliphatic amine or a tertiary aromatic amine, but is preferably a tertiary aromatic amine, and particularly preferably an alkyl p-dialkylaminobenzoate.

[0055] Examples of tertiary aliphatic amines include N,N-dimethylaminoethyl methacrylate and triethanolamine.

[0056] Examples of alkyl p-dialkylaminobenzoates include methyl p-dimethylaminobenzoate, ethyl p-dimethylaminobenzoate, propyl p-dimethylaminobenzoate, amyl p-dimethylaminobenzoate, isoamyl p-dimethylaminobenzoate, ethyl p-diethylaminobenzoate, and propyl p-diethylaminobenzoate.

[0057] Examples of tertiary aromatic amines other than alkyl p-dialkylaminobenzoates include 7-dimethylamino-4-methylcoumarin, N,N-dimethylaniline, N,N-dibenzylaniline, N,N-dimethyl-p-toluidine, N,N-diethyl-p-toluidine, N,N-bis(2-hydroxyethyl)-p-toluidine, N,N,2,4,6-pentamethylaniline, N,N,2,4-tetramethylaniline, and N,N-diethyl-2,4,6-trimethylaniline.

[0058] The tertiary amines may be used alone or in combination of two or more kinds.

[0059] Examples of the polymerization inhibitor include dibutylhydroxytoluene, 6-tert-butyl-2,4-xylenol, and 2,6-di-tert-butyl-p-cresol, and two or more of these may be used in combination.

[0060] Since the dental composition of this embodiment contains a thiourea derivative, it is preferable that the dental composition of this embodiment does not contain an oxidizing agent for the chemical polymerization initiator, which further improves the storage stability of the dental composition of this embodiment.

[0061] The dental composition of the present embodiment may further contain a reducing agent for the chemical polymerization initiator other than a thiourea derivative and a tertiary amine.

[0062] <Dental Restoration Kit> The dental repair kit of this embodiment includes the dental composition of this embodiment.

[0063] When the dental composition of the present embodiment is used as a primer, it can be used as a dental restoration kit by combining it with a known resin cement (see, for example, Patent Documents 1 and 2). Specifically, the primer is applied to the tooth surface or a prosthesis, and the prosthesis is then bonded to the tooth surface with the resin cement to restore the tooth.

[0064] The resin cement contains a (meth)acrylate and an oxidizing agent for a chemical polymerization initiator, and may further contain, as necessary, a photopolymerization initiator, a tertiary amine, a reducing agent for the chemical polymerization initiator, a polymerization inhibitor, etc. The resin cement may also further contain a polymerization accelerator, an antibacterial agent, a fluorescent agent, a pigment, etc.

[0065] Examples of the oxidizing agent for the chemical polymerization initiator include benzoyl peroxide, cumene hydroperoxide, t-butyl hydroperoxide, t-amyl hydroperoxide, 1,1,3,3-tetramethylbutyl hydroperoxide, 2,5-dimethyl-2,5-bis(hydroperoxy)hexane, p-diisopropylbenzene monohydroperoxide, p-methane hydroperoxide, and pinane hydroperoxide, and two or more of these may be used in combination.

[0066] The resin cement may be a self-adhesive type containing a (meth)acrylate having an acid group, or may be a type used in combination with a primer that does not contain a (meth)acrylate having an acid group.

[0067] Examples of materials that can be used to form prostheses include alloys containing precious metals, ceramics such as zirconia and alumina, and resins.

[0068] Furthermore, when the dental composition of this embodiment is used as a bonding material, it can be used as a dental restoration kit by combining it with a known filling composite resin (for example, see Patent Document 3). Specifically, the bonding material is applied to the cavity, and the composite resin is then directly filled into the cavity to restore it. [Example]

[0069] Examples of the present invention will be described below, but the present invention is not limited to these examples.

[0070] <Examples 1 to 10 and Comparative Examples 1 to 3> Dental compositions were prepared by mixing methacrylate without an acid group, methacrylate with an acid group, water-soluble organic solvent, water, photopolymerization initiator, tertiary amine, polymerization inhibitor, filler, thiourea derivative, and diaryl iodonium salt in the formulations [mass %] shown in Table 1.

[0071] The silica powder in Table 1 is fumed silica R972 (manufactured by Nippon Aerosil).

[0072] Next, the adhesiveness of resin when the dental composition was used as a primer and a bonding material, and the storage stability of the dental composition were evaluated.

[0073] <Resin adhesion when used as a primer> A stainless steel rod with a diameter of 10 mm was polished with waterproof abrasive paper #120 and then sandblasted to prepare a jig for the tensile test.

[0074] The dentin of bovine teeth was polished with waterproof abrasive paper #320, and a 100 μm thick polytetrafluoroethylene seal with a 2.5 mm diameter hole was attached to the flattened surface to determine the area of ​​the adhesive surface.

[0075] The dental composition was applied to the surface of bovine dentin to be bonded, left for 10 seconds, and then dried with an air blower.

[0076] An appropriate amount of a kneaded self-adhesive resin cement, G-Cem Link Ace (manufactured by GC), was applied to a tensile test jig and pressed against the dentin surface of a bovine tooth. Excess cement was then removed with a probe and the jig was immersed in water at 37°C overnight to prepare the test specimen.

[0077] Using a precision universal testing machine Autograph AG-I (Shimadzu Corporation), tensile tests were performed on five specimens at a crosshead speed of 1 mm / min, and the average tensile strength was calculated to evaluate the adhesiveness of the resin when the dental composition was used as a primer. The criteria for evaluating the adhesiveness of the resin were as follows:

[0078] Pass: The average tensile strength is 8 MPa or more Fail: The average tensile strength is less than 8 MPa <Adhesion of resin when used as a bonding material> The dentin of bovine teeth was polished with waterproof abrasive paper #320, and the polished surface was made flat and used as the bonding surface.

[0079] The dental composition was applied to the dentin surface of bovine teeth, left for 10 seconds, and then dried by air blowing. Next, a 2.38 mm diameter ULTRADENT mold was irradiated with light using a G-Light Prima light irradiator (manufactured by GC) at mode F5. Next, Clearfil AP-X (manufactured by Kuraray) was filled into the mold as a composite resin, and then irradiated with light using a G-Light Prima at mode 20 to harden it. The mold was then immersed overnight in water at 37°C to prepare a test specimen.

[0080] Using a precision universal testing machine Autograph AG-I (Shimadzu Corporation), a shear test was carried out on five specimens at a crosshead speed of 1 mm / min, and the average shear strength was calculated to evaluate the adhesiveness of the dental composition when used as a bonding material. The criteria for resin adhesiveness are as follows:

[0081] Pass: The average shear strength is 20 MPa or more Fail: The average shear strength is less than 20 MPa <Storage stability> The dental composition was placed in a high-density polyethylene container, sealed, and then left in an environment at 60°C. The number of days until the dental composition gelled was visually confirmed to evaluate the storage stability of the dental composition. The criteria for judging storage stability are as follows:

[0082] Pass: If the dental composition gels for 8 days or more Fail: Dental composition gels in less than 8 days Table 1 shows the evaluation results of the adhesiveness of resin when the dental composition was used as a primer and a bonding material, and the storage stability of the dental composition.

[0083] [Table 1] It can be seen from Table 1 that the dental compositions of Examples 1 to 10 have high resin adhesiveness and storage stability when used as a primer and bonding material.

[0084] In contrast, the dental composition of Comparative Example 1 does not contain a thiourea derivative, and therefore exhibits poor adhesiveness to resin when used as a primer.

[0085] Furthermore, the dental compositions of Comparative Examples 2 and 3 did not contain a diaryliodonium salt, and therefore had poor adhesiveness to the resin when used as a bonding material.

[0086] This application claims priority from basic application No. 2019-177799, filed with the Japan Patent Office on September 27, 2019, the entire contents of which are incorporated herein by reference.

Claims

1. A one-component dental composition, A composition comprising a (meth)acrylate, a photopolymerization initiator, a thiourea derivative, a water-soluble organic solvent, and water, Does not contain vanadium compounds the photopolymerization initiator comprises diphenyliodonium hexafluorophosphate or bis(4-tert-butylphenyl)iodonium hexafluorophosphate; The content of the photopolymerization initiator is 0.5 to 5% by mass, The dental composition, wherein the thiourea derivative is a compound selected from ethylene thiourea, N-methyl thiourea, N-ethyl thiourea, N-propyl thiourea, N-butyl thiourea, N-lauryl thiourea, N-phenyl thiourea, N-cyclohexyl thiourea, N,N-dimethyl thiourea, N,N-diethyl thiourea, N,N-dipropyl thiourea, N,N-dibutyl thiourea, N,N-dilauryl thiourea, N,N-diphenyl thiourea, N,N-dicyclohexyl thiourea, trimethyl thiourea, tetramethyl thiourea, N-acetyl thiourea, N-benzoyl thiourea, 1-allyl-3-(2-hydroxyethyl)-2-thiourea, 1-(2-tetrahydrofurfuryl)-2-thiourea, N-tert-butyl-N'-isopropyl thiourea, and 2-pyridyl thiourea.

2. The dental composition of claim 1 , which is a primer or a bonding material.

3. 2. The dental composition according to claim 1, wherein the water content is 4 to 30% by mass.

4. The dental composition according to claim 1 , wherein the mass ratio of the water-soluble organic solvent to the water is 1.3 or more.

5. A dental restoration kit comprising the dental composition of claim 1.

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