Curable composition for dental use

Abstract

The present invention provides a curable composition for dental use, which has ion release properties and aesthetic properties and is excellent in terms of mechanical strength and dentine strengthening ability. The present invention pertains to a curable composition for dental use, which contains a glass (A), a polymerizable monomer (B), and a polymerization initiator (C), wherein the glass (A) contains strontium, zinc, boron, and fluorine, the content of strontium is 8-33 mass%, the content of zinc is 2.0-25 mass%, the content of boron is 1.0-11 mass%, the content of fluorine is 9-35 mass%, and the content of sodium is 0-0.5 mass% when the contents are expressed in mass% in terms of the contents of the respective constituent elements with respect to the whole mass of the glass (A).

Description

Dental curable composition

[0001] The present invention relates to a dental hardenable composition suitable for dental filling and restorative materials, dental cements, and dental core build-up materials.

[0002] Dental composite resins, which are primarily composed of polymerizable monomers, fillers, and polymerization initiators, are currently the most widely used dental materials for repairing missing or decayed teeth, bonding dental prostheses, and other purposes, such as dental filling and restorative materials, dental cements, and dental core construction materials. The following improvements are desired for such dental composite resins: For the cured product, improvements in mechanical strength and reduction in polymerization shrinkage during curing are desired.

[0003] Secondary caries occurs when bacteria invade construction gaps caused by improper treatment, peeling of dental composite resin from the adhesive surface, or deterioration of the dental composite resin at the adhesive surface, and there is a strong desire to prevent this secondary caries as much as possible. A common method for preventing secondary caries is to strengthen the tooth structure by forming an acid-resistant layer on it. One method for strengthening tooth structure is to supply ions, including fluoride ions, to the tooth structure. Specifically, this can be done by incorporating ion-releasing compounds into dental composite resins or by using a material called glass ionomer, which is a mixture of an inorganic compound and polycarboxylic acid.

[0004] However, when an ion-releasing compound is incorporated into a dental composite resin, not only is sufficient ion release not achieved, but strength and adhesive durability are impaired due to factors such as water absorption. Furthermore, while glass ionomers have excellent ion release properties, they have the problem of low strength. Non-Patent Document 1, for example, describes a dental composite resin that uses a dimethacrylate containing a urethane bond, 2-hydroxyethyl methacrylate, polycarboxylic acid, and fluoroaluminosilicate glass as a technology for developing strength while preventing secondary caries.

[0005] Osvaldo Zmener, et al., “Resistance against bacterial leakage of four luting agents used for cementation of complete cast crowns”, American Journal of Dentistry, (USA), February, 2014, Vol. 27, No. 1, p. 51-55

[0006] However, according to the investigations conducted by the present inventors, the dental curable composition described in Non-Patent Document 1 had a low level of mechanical strength, although it had a certain level of ion release. In addition, there was room for improvement in the ability to strengthen tooth structure by ion release.

[0007] Therefore, an object of the present invention is to provide a dental hardenable composition that has ion-releasing properties, aesthetic properties, and excellent mechanical strength and tooth structure strengthening properties.

[0008] That is, the present invention includes the following inventions: [1] A dental curable composition comprising glass (A), a polymerizable monomer (B), and a polymerization initiator (C), wherein the glass (A) contains strontium, zinc, boron, and fluorine, and wherein the strontium content is 8 to 33 mass %, the zinc content is 2.0 to 25 mass %, the boron content is 1.0 to 11 mass %, the fluorine content is 9 to 35 mass %, and the sodium content is 0 to 0.5 mass %, expressed in mass % of the total constituent elements of the glass (A). [2] The dental curable composition according to [1], wherein the polymerizable monomer (B) contains a hydrophilic (meth)acrylic monomer (B-1) containing two or more (meth)acryloyloxy groups per molecule, and a hydrophobic (meth)acrylic monomer (B-2) containing two or more (meth)acryloyloxy groups per molecule. [3] The dental curable composition according to [1] or [2], wherein the polymerizable monomer (B) further contains a mono(meth)acrylic monomer (B-3) that contains no hydroxyl group, acidic group, amino group, or amide group in one molecule. [4] The dental curable composition according to any one of [1] to [3], wherein, per 100 parts by mass of the polymerizable monomer (B), the dental curable composition contains: 5 to 55 parts by mass of a hydrophilic (meth)acrylic monomer (B-1) containing two or more (meth)acryloyloxy groups in one molecule; 25 to 70 parts by mass of a hydrophobic (meth)acrylic monomer (B-2) containing two or more (meth)acryloyloxy groups in one molecule; and 0 to 55 parts by mass of a mono(meth)acrylic monomer (B-3) that contains no hydroxyl group, acidic group, amino group, or amide group in one molecule. [5] The glass (A) further contains aluminum and silicon, and a silane-treated glass powder obtained by surface-treating 100 parts by mass of the crushed glass of the glass (A) with 1.5 parts by mass of γ-methacryloyloxypropyltrimethoxysilane is measured. The strontium ion elution amount (W Sr ) and the sum of the amount of aluminum ion elution and the amount of silicon ion elution (W Al + Si ) and the ratio (W Sr ) / (WAl+Si ) is 10 or more. [6] The dental curable composition according to any one of [1] to [5], wherein the dental curable composition is substantially free of polyacid. [7] The dental curable composition according to any one of [1] to [6], wherein the polymerization initiator (C) contains a chemical polymerization initiator (C-2). [8] The dental curable composition according to any one of [1] to [7], further containing a polymerization accelerator (D). [9] The dental curable composition according to any one of [1] to [8], wherein the dental curable composition is divided into a first material and a second material and packaged.

[10] The dental curable composition according to [9], wherein the first material contains a chemical polymerization initiator (C-2), and the second material contains a polymerization accelerator (D).

[0009] According to the present invention, a dental hardenable composition can be provided that has ion-releasing properties, aesthetic properties, excellent mechanical strength, and tooth structure strengthening ability, and also has excellent X-ray contrast properties.

[0010] The present invention will be described in detail below using embodiments. In this specification, the upper and lower limits of numerical ranges (such as the content of each component, values ​​calculated from each component, and physical properties) can be combined as appropriate. Furthermore, in this specification, the numerical values ​​of each symbol in a formula can also be combined as appropriate. That is, in this specification, the lower and upper limits described in stages for a numerical range can be independently combined. For example, a description of the same item, "preferably 10 to 90, more preferably 30 to 60," can be combined with a "preferable lower limit (10)" and a "more preferable upper limit (60)" to form "10 to 60." Furthermore, for a numerical range, for example, based on a description of "preferably 10 to 90, more preferably 30 to 60," the upper limit can be specified as "10 or more" or "30 or more" without specifying a specific upper limit. Similarly, the upper limit can be specified as "90 or less" or "60 or less" without specifying a specific lower limit. Unless otherwise specified, when a numerical range is simply stated as "10 to 90," it represents a range of 10 or more and 90 or less. As described above, for example, from the description of "preferably 10 or more, more preferably 30 or more" and the description of "preferably 90 or less, more preferably 60 or less" for the same item, the "preferable lower limit (10)" and the "more preferable upper limit (60)" can be combined to form "10 or more and 60 or less." Similarly, as described above, only the lower limit can be specified as "10 or more" or "30 or more," and similarly, only the upper limit can be specified as "90 or less" or "60 or less." Furthermore, in this specification, the term "(meth)acrylic" is used to encompass both "methacrylic" and "acrylic." The same applies to similar terms such as "(meth)acrylate," "(meth)acrylic acid ester," "(meth)acrylamide," and "(meth)acryloyloxy." In addition, in this specification, the expressions "(meth)acrylic monomer" or "(meth)acrylic compound" are used to mean both "(meth)acrylic acid ester compound" and "(meth)acrylamide and its derivatives."In this specification, the term "polymerizable monomer" refers to a (meth)acrylic compound polymerized by a polymerization initiator (C) described below. In this specification, unless otherwise specified, the terms "hardenability" and "storage stability" refer to the "hardenability" and "storage stability" of the dental hardenable composition of one embodiment of the present invention. In this specification, unless otherwise specified, the term "ion-releasing" refers to the "silicon ion-releasing," "aluminum ion-releasing," "zinc ion-releasing," and "strontium ion-releasing" of the cured product of the dental hardenable composition of one embodiment of the present invention. In this specification, unless otherwise specified, the terms "mechanical strength" or "strength" refer to the "flexural strength" and "flexural modulus" of the cured product of the dental hardenable composition of one embodiment of the present invention. In this specification, unless otherwise specified, the term "tooth structure strengthening ability" refers to the "tooth structure strengthening ability" of the cured product of the dental hardenable composition of one embodiment of the present invention. Tooth strengthening ability is an indicator of resistance to acid-induced demineralization and is calculated as the "decalcification inhibition rate."

[0011] [Dental curable composition] The dental curable composition of the present invention contains glass (A), a polymerizable monomer (B), and a polymerization initiator (C). The polymerizable monomer preferably contains a hydrophilic (meth)acrylic monomer (B-1) containing two or more (meth)acryloyloxy groups per molecule and a hydrophobic (meth)acrylic monomer (B-2) containing two or more (meth)acryloyloxy groups per molecule, and more preferably contains a mono(meth)acrylic monomer (B-3) containing no hydroxyl group, acidic group, amino group, or amide group per molecule. Each component of the dental curable composition of the present invention will be described below.

[0012] <Glass (A)> The glass (A) is used in the dental hardenable composition to impart strength and ion release properties to the hardened product of the dental hardenable composition. The glass (A) contains strontium, zinc, boron, and fluorine. By containing strontium, zinc, and fluorine, strontium ions, zinc ions, and fluorine ions are released, and these ions are taken up by the tooth structure, thereby improving the tooth structure's resistance to demineralization by acid. Furthermore, the glass (A) contains silicon and aluminum as its basic structure, and boron is thought to control the strength of the basic structure. If the basic structure is excessively rigid, it is presumed that the amount of ion release is limited, suppressing the tooth structure strengthening ability. If the basic structure is excessively fragile, it is presumed that the strength is reduced.

[0013] The contents of each component in the glass (A) are expressed in mass% of the constituent elements in the entire glass (A), with the strontium content being 8 to 33 mass%, the zinc content being 2.0 to 25 mass%, the boron content being 1.0 to 11 mass%, the fluorine content being 9 to 35 mass%, and the sodium content being 0 to 0.5 mass%. Hereinafter, the contents of each component refer to the mass% of the constituent elements in the entire glass (A).

[0014] The mechanism by which strontium enhances the ability to strengthen tooth structure is unclear, but is presumed to be as follows. It is believed that the partial substitution of calcium ions contained in tooth structure with strontium ions makes the tooth structure acid-resistant, thereby reducing the amount of calcium ions eluted from the tooth structure due to demineralization. If the strontium content is less than 8% by mass, the ability to strengthen tooth structure decreases. If the strontium content exceeds 33% by mass, crystals are more likely to precipitate during glass production, potentially causing the glass to devitrify. From the viewpoint of excellent ability to strengthen tooth structure, the strontium content is preferably 9 to 32% by mass, more preferably 10 to 31% by mass, even more preferably 10.5 to 30% by mass, and particularly preferably 11 to 29% by mass.

[0015] Although the mechanism by which zinc enhances tooth strengthening ability is unclear, it is believed that zinc ions also partially replace calcium ions contained in tooth tissue, thereby imparting acid resistance to the tooth tissue and reducing the amount of calcium ions eluted from the tooth tissue due to demineralization, thereby enhancing tooth strengthening ability. If the zinc content is less than 2.0% by mass, tooth strengthening ability decreases, and if it exceeds 25% by mass, crystals are more likely to precipitate during glass production, which may cause the glass to devitrify. In terms of excellent tooth strengthening ability, the zinc content is preferably 2.5 to 23% by mass, more preferably 3 to 20% by mass, even more preferably 3.5 to 18% by mass, and particularly preferably 3.5 to 16% by mass.

[0016] The boron content is 1.0 to 11 mass %, preferably 1.2 to 10 mass %, more preferably 1.5 to 9.5 mass %, even more preferably 1.7 to 9.3 mass %, and particularly preferably 2.0 to 9.0 mass %, from the viewpoints of achieving both strength and sustained ion release properties, controlling the tooth substance strengthening ability by controlling the strength of the basic structure, and preventing devitrification during glass production.

[0017] The mechanism by which fluoride strengthens tooth structure is that the released fluoride ions penetrate the hydroxyapatite (Ca 10 (PO4)6(OH2)) to form fluorapatite (Ca 10 It is believed that the fluorine content is converted to (PO4)6(F2)), improving the acid resistance of the tooth structure. If the fluorine content is less than 9% by mass, the refractive index of the glass (A) may exceed 1.6, making it difficult to prepare a dental hardenable composition. If the fluorine content exceeds 35% by mass, crystals may precipitate easily during glass production, causing the glass to devitrify. From the viewpoint of excellent tooth structure strengthening ability, the fluorine content is preferably 10 to 34% by mass, more preferably 10.5 to 33% by mass, even more preferably 11 to 32% by mass, and particularly preferably 12 to 30% by mass.

[0018] Furthermore, if the sodium content in glass (A) exceeds 0.5 mass%, crystals are likely to precipitate during glass production, potentially causing devitrification of the glass. Therefore, the sodium content is 0 to 0.5 mass%. The sodium content is preferably 0 to 0.3 mass%, more preferably 0 to 0.1 mass%, even more preferably 0 to 0.01 mass%, and particularly preferably 0 to 0.001 mass%. In a preferred embodiment, the sodium content may be 0 mass%. Furthermore, known alkali metals (lithium, potassium, rubidium, cesium, and francium) can be used without any restrictions as alkali metals other than sodium. The contents of the alkali metals other than sodium can be the same as the sodium content. Furthermore, if the alkali metal content exceeds 0.5 mass%, crystals are likely to precipitate during glass production, potentially causing devitrification of the glass. Therefore, the total alkali metal content is preferably 0 to 0.5 mass%.

[0019] The glass (A) preferably contains aluminum and silicon. The aluminum content is not particularly limited as long as the effects of the present invention are achieved, but from the viewpoints of achieving both strength and ion-releasing properties and preventing devitrification during glass production, the aluminum content is preferably 2 to 15 mass%, more preferably 2.1 to 14 mass%, even more preferably 2.2 to 13 mass%, and particularly preferably 2.3 to 12.5 mass%.

[0020] Furthermore, the silicon content is not particularly limited as long as the effects of the present invention are achieved, but from the viewpoint of achieving both strength and ion-releasing properties and preventing devitrification during glass production, the silicon content is preferably 5 to 25 mass%, more preferably 6 to 24 mass%, even more preferably 6.5 to 22 mass%, and particularly preferably 7 to 20 mass%.

[0021] In a preferred embodiment, the dental hardenable composition includes glass (A) having a silicon content of 5 to 25 mass %, an aluminum content of 2 to 15 mass %, and a boron content of 1.0 to 11 mass %.

[0022] In the dental hardenable composition of the present invention, a silane-treated glass powder obtained by surface-treating 100 parts by mass of crushed glass (A) with 1.5 parts by mass of γ-methacryloyloxypropyltrimethoxysilane is used. The amount of strontium ion elution (W) of the silane-treated glass powder obtained by immersing the silane-treated glass powder in distilled water at 37°C at a concentration of 5% by mass for 24 hours is Sr ) and the sum of the amount of aluminum ion elution and the amount of silicon ion elution (W Al + Si ) and the ratio of the amount of eluted ions (W Sr ) / (W Al+Si ) is preferably 10 or more. Sr ) / (W Al+Si ) is more preferably 12 or more, even more preferably 15 or more, particularly preferably 18 or more, and most preferably 25 or more. Sr ) / (W Al+Si The measurement method for the above is as described in the Examples below.

[0023] Glass (A) may also contain other components from the viewpoints of X-ray contrast and sustained ion release. Examples of other components include titanium, barium, ytterbium, hafnium, zirconium, yttrium, tin, tantalum, antimony, vanadium, cerium, europium, praseodymium, tungsten, germanium, niobium, lanthanum, copper, iron, bismuth, chromium, manganese, cobalt, terbium, phosphorus, and alkaline earth metals (calcium, barium, radium, beryllium, and magnesium). The content of these other components is preferably less than 3% by mass, more preferably less than 1% by mass, even more preferably less than 0.1% by mass, and particularly preferably less than 0.001% by mass. The remainder of glass (A) is oxygen.

[0024] The components contained in the glass (A) can be determined by any known technique without any limitation, for example, by fluorescent X-ray analysis.

[0025] The shape of the glass (A) is not particularly limited and may be any particulate shape, such as spherical, needle-like, plate-like, crushed, or scaly. The glass (A) may also be dissolved in a polymerizable monomer or the like. When the glass (A) is particulate, the average primary particle size is preferably 0.001 to 10 μm, more preferably 0.005 to 8.0 μm, even more preferably 0.01 to 6.0 μm, and particularly preferably 1.0 to 5.0 μm, from the viewpoints of the handleability of the dental curable composition and the ion release, mechanical strength, and transparency of the cured product. Any known method can be used to obtain glass (A) of a predetermined particle size, and examples of such methods include ball mill pulverization and bead mill pulverization. In this specification, the average primary particle size of glass (A) can be determined by laser diffraction scattering, optical microscopy, or electron microscopy. More specifically, laser diffraction scattering or optical microscope observation is convenient for measuring particle diameters of 100 nm or more, while electron microscope observation is convenient for measuring particle diameters of less than 100 nm.

[0026] From the viewpoint of aesthetics as a dental hardenable composition, the refractive index of the glass (A) is preferably 1.500 to 1.600. If the refractive index is less than 1.500 or more than 1.600, the difference in refractive index with the polymerizable monomer (B) becomes too large, which may reduce the translucency of the dental hardenable composition and impair its aesthetics. The refractive index of the glass is measured in accordance with the refractive index measurement method of JIS B 7071-2:2018.

[0027] In order to adjust the miscibility with the polymerizable monomer (B), the glass (A) may be surface-treated in advance with a known surface treatment agent such as polysiloxane, polyethylene glycol, fatty acid amide, silane coupling agent, etc., within a range that does not impair ion-releasing properties. However, it is preferable not to carry out a strong coating treatment such as coating with an ion-releasing compound such as silica coating, or to form a core-shell structure, because these impair ion-releasing properties.

[0028] The surface treatment method can be any known method without any particular limitation, and examples thereof include: (1) a method in which a layer made of a silanol compound is formed on the surface of the glass (A), and then the silanol groups are subjected to intermolecular dehydration condensation; and (2) a method in which a hydrolyzable silane compound is (partially) hydrolyzed to oligomerize the silanol groups through intermolecular dehydration condensation, a powdered ion-releasing compound is added to the siloxane oligomer, a layer made of the siloxane oligomer is formed on the surface of the ion-releasing compound, and then the siloxane oligomer is subjected to intermolecular dehydration condensation to polymerize.

[0029] In the method (1), first, a hydrolyzable silane compound and a required amount of water are added to a water-miscible organic solvent such as methanol, ethanol, or t-butanol, and the hydrolyzable silane compound is (partially) hydrolyzed in the presence of an acid catalyst to prepare an organic solution containing a silanol compound, which is the hydrolysis product. Examples of the silane compound include vinyl group-containing silane compounds such as vinyltrimethoxysilane, vinyltriethoxysilane, vinyltrichlorosilane, and vinyltri(β-methoxyethoxy)silane; (meth)acryloyl group-containing silane compounds such as γ-(meth)acryloyloxypropyltrimethoxysilane, 8-(meth)acryloyloxyoctyltrimethoxysilane, 11-(meth)acryloyloxyundecyltrimethoxysilane, γ-(meth)acryloyloxypropylmethyldimethoxysilane, γ-(meth)acryloyloxypropylmethyldiethoxysilane, and γ-(meth)acryloyloxypropyldimethylmonomethoxysilane; amino group-containing silane compounds such as γ-aminopropyltriethoxysilane; epoxy group-containing silane compounds such as γ-glycidoxypropyltrimethoxysilane; and mercapto group-containing silane compounds such as γ-mercaptopropyltrimethoxysilane. The organic solution containing the silanol compound can also be prepared by adding excess water to a hydrolyzable silane compound and (partially) hydrolyzing it in the presence of an acid catalyst to prepare an aqueous solution containing the silanol compound, and then extracting the silanol compound in the aqueous solution using a water-immiscible organic solvent such as ethyl acetate, ethyl ether, chloroform, or methylene chloride as an extractant. Powdered glass (A) is then added to the organic solution obtained by these methods, and the organic solvent is evaporated by heat treatment or reduced pressure treatment to obtain glass (A) consisting of composite particles in which the silanol compound is adhered in the form of a layer to the surface of the glass (A). Next, an acid or base is added as needed, and the glass (A) is then heated to cause intermolecular dehydration condensation of the silanol groups, thereby producing glass (A) consisting of composite particles in which a layer of polysiloxane is formed on the surface of the glass (A).

[0030] In method (2), a predetermined amount of water is first added to a hydrolyzable silane compound, and in the presence of an acid catalyst, the compound is (partially) hydrolyzed while distilling off the by-product alcohol to produce a siloxane oligomer. Powdered glass (A) is added to this siloxane oligomer, a layer of siloxane oligomer is formed on the particle surface, and after adding an acid or base as necessary, heat treatment is performed to cause intermolecular dehydration condensation of silanol groups in the siloxane oligomer, producing glass (A) consisting of composite particles in which a layer of polysiloxane is formed on the surface of a base particle made of glass (A).

[0031]

[0032] The content of glass (A) in the dental hardenable composition is not particularly limited as long as the effects of the present invention are achieved, but from the viewpoint of more easily achieving the effects of the present invention, it is preferably 30 parts by mass or more, more preferably 40 parts by mass or more, and even more preferably 50 parts by mass or more, relative to 100 parts by mass of the total amount of the polymerizable monomer (B). The content of glass (A) is preferably 1,000 parts by mass or less, more preferably 900 parts by mass or less, and even more preferably 850 parts by mass or less, relative to 100 parts by mass of the total amount of the dental hardenable composition. In a preferred embodiment, the content of glass (A) in the dental hardenable composition is preferably 20 to 95% by mass, more preferably 25 to 94% by mass, relative to 100% by mass of the total amount of the dental hardenable composition. From the viewpoint of more excellent ion release properties of the cured product, it is more preferably 30 to 92% by mass, and particularly preferably 35 to 90% by mass.

[0032] <Hydrophilic (meth)acrylic monomer (B-1) containing two or more (meth)acryloyloxy groups per molecule> The dental curable composition of the present invention preferably contains, as the polymerizable monomer component (B), the hydrophilic (meth)acrylic monomer (B-1) containing two or more (meth)acryloyloxy groups per molecule (hereinafter also referred to simply as "hydrophilic polyfunctional (meth)acrylic monomer (B-1)"). The hydrophilic polyfunctional (meth)acrylic monomer (B-1) refers to a polyfunctional polymerizable monomer having a solubility in water at 25°C of 5% by mass or more, preferably 10% by mass or more, and more preferably 15% by mass or more.

[0033] The hydrophilic polyfunctional (meth)acrylic monomer (B-1) is used in the dental curable composition to impart adhesive properties to the dental curable composition and to impart ion-releasing properties to the cured product of the dental curable composition. The hydrophilic polyfunctional (meth)acrylic monomer (B-1) increases ionic conductivity, facilitating the uptake of released ions into tooth structure, thereby acting in unison with components such as strontium ions and zinc ions to enhance tooth structure strengthening. Furthermore, since the hydrophilic polyfunctional (meth)acrylic monomer (B-1) contains two or more (meth)acryloyloxy groups per molecule, the cured product has excellent mechanical strength. The number of (meth)acryloyloxy groups per molecule of the hydrophilic polyfunctional (meth)acrylic monomer (B-1) is not particularly limited, as long as it is two or more.

[0034] The hydrophilic polyfunctional (meth)acrylic monomer (B-1) has a hydrophilic group such as a hydroxyl group, an oxymethylene group, an oxyethylene group, an oxypropylene group, or an amide group. Examples of the hydrophilic polyfunctional (meth)acrylic monomer (B-1) include polyfunctional (meth)acrylate compounds such as glycerol di(meth)acrylate, 1,2-bis(3-(meth)acryloyloxy-2-hydroxypropoxy)ethane, 2,2-bis[4-(3-(meth)acryloyloxy)-2-hydroxypropoxyphenyl]propane, and pentaerythritol tri(meth)acrylate. These may be used alone or in combination of two or more. Among these, from the viewpoint of excellent effects of improving the adhesion durability of the dental curable composition to tooth structure and the ion release properties of the cured product, bifunctional (meth)acrylate compounds such as glycerol di(meth)acrylate and 1,2-bis(3-(meth)acryloyloxy-2-hydroxypropoxy)ethane are preferred, and glycerol dimethacrylate and 1,2-bis(3-methacryloyloxy-2-hydroxypropoxy)ethane are more preferred.

[0035] The content of the hydrophilic polyfunctional (meth)acrylic monomer (B-1) in the dental curable composition is preferably 1 to 60 parts by mass, more preferably 2 to 50 parts by mass, based on 100 parts by mass of the total amount of polymerizable monomers (B) in the dental curable composition. From the viewpoint of achieving superior ion release properties of the cured product, the ...% by mass, more preferably 2 to 50% by mass, based on 100 parts by mass of the total amount of the dental curable composition. From the viewpoint of achieving superior ion release properties of the cured product, the content of the hydrophilic polyfunctional (meth)acrylic monomer (B-1) in the dental curable composition is more preferably 2 to 50% by mass, based on 100 parts by mass of the total amount of the dental curable composition. From the viewpoint of achieving superior ion release properties of the cured product, the content of the hydrophilic polyfunctional (meth)acrylic monomer (B-1) in the dental curable composition is more preferably 2.5 to 55% by mass, and particularly preferably 3 to 40% by mass.

[0036] <Hydrophobic (meth)acrylic monomer (B-2) containing two or more (meth)acryloyloxy groups in one molecule> The dental curable composition of the present invention preferably contains, as the polymerizable monomer component (B), the hydrophobic (meth)acrylic monomer (B-2) containing two or more (meth)acryloyloxy groups in one molecule (hereinafter also referred to simply as "hydrophobic polyfunctional (meth)acrylic monomer (B-2)"). The hydrophobic polyfunctional (meth)acrylic monomer (B-2) refers to a polyfunctional polymerizable monomer having a solubility in water at 25°C of less than 5% by mass.

[0037] The hydrophobic polyfunctional (meth)acrylic monomer (B-2) is used in the dental curable composition to impart strength to the dental curable composition. Examples of the hydrophobic polyfunctional (meth)acrylic monomer (B-2) include aromatic compound-based bifunctional polymerizable monomers, aliphatic compound-based bifunctional polymerizable monomers, and trifunctional or higher functional polymerizable monomers.

[0038] Examples of aromatic compound-based bifunctional polymerizable monomers include 2,2-bis((meth)acryloyloxyphenyl)propane, 2,2-bis[4-(2-hydroxy-3-(meth)acryloyloxypropoxy)phenyl]propane, 2,2-bis(4-(meth)acryloyloxyethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxypolyethoxyphenyl)propane (average number of moles of ethoxy groups added: 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, 2,2-bis(4-(meth)acryloyloxytetraethoxyphenyl)propane,

[0033] Examples of such methacryloyloxy include methacryloyloxypentaethoxyphenyl, 2,2-bis(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, and 2,2-bis(4-(meth)acryloyloxyisopropoxyphenyl)propane.Among these, 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-(meth)acryloyloxypolyethoxyphenyl)propane (average number of moles of ethoxy groups added: 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.

[0039] Examples of the aliphatic compound-based bifunctional polymerizable monomers include 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 2,2,4-trimethylhexamethylenebis(2-carbamoyloxyethyl)di(meth)acrylate. Among these, triethylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 1,2-bis(3-methacryloyloxy-2-hydroxypropoxy)ethane, and 2,2,4-trimethylhexamethylenebis(2-carbamoyloxyethyl)dimethacrylate (commonly known as "UDMA") are preferred.

[0040] Examples of trifunctional or higher functional polymerizable monomers 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.

[0041] Among the hydrophobic polyfunctional (meth)acrylic monomers (B-2), aromatic compound-based bifunctional polymerizable monomers and aliphatic compound-based bifunctional polymerizable monomers are preferably used from the viewpoints of mechanical strength and handleability. Bis-GMA and D-2.6E are preferred as aromatic compound-based bifunctional polymerizable monomers. Triethylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,10-decanediol di(meth)acrylate, 1,2-bis(3-methacryloyloxy-2-hydroxypropoxy)ethane, and UDMA are preferred as aliphatic compound-based bifunctional polymerizable monomers.

[0042] The hydrophobic polyfunctional (meth)acrylic monomer (B-2) may be used alone or in combination of two or more. The content of the hydrophobic polyfunctional (meth)acrylic monomer (B-2) is preferably 10 to 80 parts by mass, more preferably 20 to 75 parts by mass, per 100 parts by mass of the total amount of the polymerizable monomer (B) in the dental curable composition. From the viewpoint of achieving superior mechanical strength of the cured product, it is even more preferably 25 to 70 parts by mass, and particularly preferably 30 to 60 parts by mass. If the content of the hydrophobic polyfunctional (meth)acrylic monomer (B-2) is excessive, the ionic conductivity may decrease, resulting in a decrease in the tooth structure strengthening ability. On the other hand, if the content is too low, the effect of improving mechanical strength may not be sufficiently obtained. In a preferred embodiment, the content of the hydrophobic polyfunctional (meth)acrylic monomer (B-2) in the dental curable composition is preferably 1 to 60% by mass, more preferably 2 to 50% by mass, and from the viewpoint of obtaining a cured product with better ion release properties, still more preferably 3 to 55% by mass, and particularly preferably 4 to 40% by mass, relative to 100% by mass of the total amount of the dental curable composition.

[0043] <Mono(meth)acrylic monomer (B-3) containing no hydroxyl group, acidic group, amino group, or amide group in one molecule> Preferably, the polymerizable monomer (B) of the dental curable composition further contains a mono(meth)acrylic monomer (B-3) containing no hydroxyl group, acidic group, amino group, or amide group in one molecule (hereinafter also referred to simply as "mono(meth)acrylic monomer (B-3)"). The mono(meth)acrylic monomer (B-3) is preferably used in the dental curable composition from the viewpoint of improving operability by reducing the viscosity of the dental curable composition and imparting the effect of improving the strength of the cured product. Examples of the acidic group include a phosphate group, a sulfo group, and a carboxy group.

[0044] Examples of the mono(meth)acrylic monomer (B-3) include aromatic compound-based monofunctional (meth)acrylic monomers and aliphatic compound-based monofunctional (meth)acrylic monomers. Examples of aromatic compound-based monofunctional (meth)acrylic monomers include o-phenylphenol(meth)acrylate, m-phenylphenol(meth)acrylate, p-phenylphenol(meth)acrylate, methoxylated-o-phenylphenol(meth)acrylate, methoxylated-m-phenylphenol(meth)acrylate, methoxylated-p-phenylphenol(meth)acrylate, ethoxylated-o-phenylphenol(meth)acrylate, ethoxylated-m-phenylphenol(meth)acrylate, ethoxylated-p-phenylphenol(meth)acrylate, propoxylated-o-phenylphenol(meth)acrylate, propoxylated-m-phenylphenol(meth)acrylate, propoxylated-p-phenylphenol(meth)acrylate, butoxylated-o-phenylphenol(meth)acrylate, butoxylated-m-phenylphenol(meth)acrylate, butoxylated-p-phenylphenol(meth)acrylate, o-phenoxy O-benzyl (meth)acrylate, m-phenoxybenzyl (meth)acrylate, p-phenoxybenzyl (meth)acrylate, 2-(o-phenoxyphenyl)ethyl (meth)acrylate, 2-(m-phenoxyphenyl)ethyl (meth)acrylate, 2-(p-phenoxyphenyl)ethyl (meth)acrylate, 3-(o-phenoxyphenyl)propyl (meth)acrylate, 3-(m-phenoxyphenyl)propyl (meth)acrylate, 3-(p-phenoxyphenyl) Propyl (meth)acrylate, 4-(o-phenoxyphenyl)butyl (meth)acrylate, 4-(m-phenoxyphenyl)butyl (meth)acrylate, 4-(p-phenoxyphenyl)butyl (meth)acrylate, 5-(o-phenoxyphenyl)pentyl (meth)acrylate, 5-(m-phenoxyphenyl)pentyl (meth)acrylate, 5-(p-phenoxyphenyl)pentyl (meth)acrylate, 6-(o-phenoxyphenyl)hexyl (meth)acrylate,Examples include (meth)acrylates containing two aromatic rings, such as 6-(m-phenoxyphenyl)hexyl (meth)acrylate and 6-(p-phenoxyphenyl)hexyl (meth)acrylate; and (meth)acrylates containing one aromatic ring, such as benzyl (meth)acrylate and phenyl (meth)acrylate. Examples of aliphatic compound-based monofunctional (meth)acrylic monomers include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, sec-butyl (meth)acrylate, t-butyl (meth)acrylate, isobutyl (meth)acrylate, n-hexyl (meth)acrylate, cyclohexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, lauryl (meth)acrylate, cetyl (meth)acrylate, stearyl (meth)acrylate, isobornyl (meth)acrylate, 2,3-dibromopropyl (meth)acrylate, 3-(meth)acryloyloxypropyltrimethoxysilane, and 11-(meth)acryloyloxyundecyltrimethoxysilane. These may be used alone or in combination of two or more.

[0045] Among these, in view of excellent workability of the dental curable composition and strength of the cured product, ethoxylated-o-phenylphenol(meth)acrylate, ethoxylated-m-phenylphenol(meth)acrylate, ethoxylated-p-phenylphenol(meth)acrylate, propoxylated-o-phenylphenol(meth)acrylate, propoxylated-m-phenylphenol(meth)acrylate, propoxylated-p-phenylphenol(meth)acrylate, o-phenoxybenzyl(meth)acrylate, m-phenoxybenzyl(meth)acrylate, p-phenoxybenzyl(meth)acrylate, 2-(o-phenoxyphenyl)ethyl(meth)acrylate, 2-(m-phenoxyphenyl)ethyl(meth)acrylate are particularly preferred.

[0043] Preferred are ethoxylated o-phenylphenol (meth)acrylate, ethoxylated m-phenylphenol (meth)acrylate, ethoxylated p-phenylphenol (meth)acrylate, o-phenoxybenzyl (meth)acrylate, m-phenoxybenzyl (meth)acrylate, p-phenoxybenzyl (meth)acrylate and lauryl (meth)acrylate, more preferred are ethoxylated o-phenylphenol (meth)acrylate, ethoxylated m-phenylphenol (meth)acrylate, o-phenoxybenzyl (meth)acrylate and m-phenoxybenzyl (meth)acrylate, even more preferred are ethoxylated o-phenylphenol (meth)acrylate, ethoxylated m-phenylphenol (meth)acrylate, o-phenoxybenzyl (meth)acrylate and m-phenoxybenzyl (meth)acrylate. In the preferred embodiments described above, methacrylate compounds are particularly preferred, with ethoxylated o-phenylphenol methacrylate, ethoxylated m-phenylphenol methacrylate, o-phenoxybenzyl methacrylate, and m-phenoxybenzyl methacrylate being most preferred.

[0046] The content of the mono(meth)acrylic monomer (B-3) is preferably 0 to 60 parts by mass, more preferably 0 to 55 parts by mass, relative to 100 parts by mass of the total amount of polymerizable monomers (B) in the dental curable composition. From the viewpoint of more easily achieving the effects of the present invention, it is even more preferably 0 to 50 parts by mass, and particularly preferably 0 to 45 parts by mass. In a preferred embodiment, when the dental curable composition contains the mono(meth)acrylic monomer (B-3), the content of the mono(meth)acrylic monomer (B-3) is preferably 5 to 60 parts by mass, more preferably 8 to 55 parts by mass, relative to 100 parts by mass of the total amount of polymerizable monomers (B) in the dental curable composition. From the viewpoint of more easily achieving the effects of the present invention, it is even more preferably 8 to 50 parts by mass, and particularly preferably 10 to 45 parts by mass. In another preferred embodiment, the content of the mono(meth)acrylic monomer (B-3) in the dental curable composition is preferably 0 to 60% by mass, more preferably 0 to 50% by mass, and from the viewpoint of obtaining a cured product with better ion release properties, is even more preferably 0 to 55% by mass, and particularly preferably 0 to 40% by mass, relative to 100% by mass of the total amount of the dental curable composition.

[0047] In one preferred embodiment, the dental curable composition contains, relative to 100 parts by mass of the total amount of the polymerizable monomer (B), 5 to 55 parts by mass of a hydrophilic (meth)acrylic monomer (B-1) containing two or more (meth)acryloyloxy groups in one molecule, 25 to 70 parts by mass of a hydrophobic (meth)acrylic monomer (B-2) containing two or more (meth)acryloyloxy groups in one molecule, and 0 to 55 parts by mass of a mono(meth)acrylic monomer (B-3) containing none of a hydroxyl group, an acidic group, an amino group, and an amide group in one molecule.

[0048] <Polymerization initiator (C)> The polymerization initiator (C) can be selected from polymerization initiators used in general industry, and among them, polymerization initiators used for dental applications are preferably used. The polymerization initiator (C) preferably contains at least one selected from the group consisting of photopolymerization initiators (C-1) and chemical polymerization initiators (C-2), more preferably contains at least photopolymerization initiator (C-1), and may contain both photopolymerization initiator (C-1) and chemical polymerization initiator (C-2). A preferred embodiment includes a dental curable composition in which the polymerization initiator (C) contains chemical polymerization initiator (C-2).

[0049] Examples of the photopolymerization initiator (C-1) include (bis)acylphosphine oxides (including salts), thioxanthones (including salts such as quaternary ammonium salts), ketals, α-diketones, coumarins, anthraquinones, benzoin alkyl ether compounds, α-aminoketone compounds, etc. These may be used alone or in combination of two or more.

[0050] Among these photopolymerization initiators (C-1), it is preferable to use at least one selected from the group consisting of (bis)acylphosphine oxides and α-diketones, which provides a curable composition that is excellent in photocurability in the visible light region and near-ultraviolet region and exhibits sufficient photocurability using any of a halogen lamp, a light-emitting diode (LED), and a xenon lamp as a light source.

[0051] 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, benzoyldi(2,6-dimethylphenyl)phosphonate, sodium salt of 2,4,6-trimethylbenzoylphenylphosphine oxide, potassium salt of 2,4,6-trimethylbenzoylphenylphosphine oxide, and ammonium salt of 2,4,6-trimethylbenzoylphenylphosphine oxide.

[0052] Among the (bis)acylphosphine oxides, 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(2,3,6-trimethylbenzoyl)-2,4,4-trimethylpentylphosphine oxide.

[0053] Further, examples of the (bis)acylphosphine oxides include the compounds described in JP-A No. 2000-159621.

[0054] Among these (bis)acylphosphine oxides, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2,4,6-trimethylbenzoylmethoxyphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, and the sodium salt of 2,4,6-trimethylbenzoylphenylphosphine oxide are more preferably used as the photopolymerization initiator (C-1).

[0055] Examples of the α-diketones include diacetyl, benzyl, camphorquinone, 2,3-pentadione, 2,3-octadione, 9,10-phenanthrenequinone, 4,4′-oxybenzyl, acenaphthenequinone, etc. Among these, camphorquinone is particularly preferred from the viewpoint of having a maximum absorption wavelength in the visible light region.

[0056] As the chemical polymerization initiator (C-2), an organic peroxide is preferably used. There are no particular limitations on the organic peroxide used as the chemical polymerization initiator (C-2), and known organic peroxides can be used. Typical organic peroxides include, for example, ketone peroxides, hydroperoxides, diacyl peroxides, dialkyl peroxides, peroxyketals, peroxyesters, and peroxydicarbonates. These may be used alone or in combination of two or more.

[0057] Examples of the ketone peroxide include methyl ethyl ketone peroxide, methyl isobutyl ketone peroxide, methyl cyclohexanone peroxide, and cyclohexanone peroxide.

[0058] Examples of the hydroperoxide include 2,5-dimethylhexane-2,5-dihydroperoxide, diisopropylbenzene hydroperoxide, cumene hydroperoxide, t-butyl hydroperoxide, and 1,1,3,3-tetramethylbutyl hydroperoxide.

[0059] Examples of the diacyl peroxide include acetyl peroxide, isobutyryl peroxide, benzoyl peroxide, decanoyl peroxide, 3,5,5-trimethylhexanoyl peroxide, 2,4-dichlorobenzoyl peroxide, and lauroyl peroxide.

[0060] Examples of the dialkyl peroxide include di-t-butyl peroxide, dicumyl peroxide, t-butylcumyl peroxide, 2,5-dimethyl-2,5-di(t-butylperoxy)hexane, 1,3-bis(t-butylperoxyisopropyl)benzene, and 2,5-dimethyl-2,5-di(t-butylperoxy)-3-hexyne.

[0061] Examples of the peroxyketals include 1,1-bis(t-butylperoxy)-3,3,5-trimethylcyclohexane, 1,1-bis(t-butylperoxy)cyclohexane, 2,2-bis(t-butylperoxy)butane, 2,2-bis(t-butylperoxy)octane, and 4,4-bis(t-butylperoxy)valeric acid n-butyl ester.

[0062] Examples of the peroxyester include α-cumyl peroxyneodecanoate, t-butyl peroxyneodecanoate, t-butyl peroxypivalate, 2,2,4-trimethylpentylperoxy-2-ethylhexanoate, t-amyl peroxy-2-ethylhexanoate, t-butyl peroxy-2-ethylhexanoate, di-t-butylperoxyisophthalate, di-t-butylperoxyhexahydroterephthalate, t-butylperoxy-3,3,5-trimethylhexanoate, t-butyl peroxyacetate, t-butyl peroxybenzoate, and t-butyl peroxymaleate.

[0063] Examples of the peroxydicarbonate include di(3-methoxybutyl)peroxydicarbonate, di(2-ethylhexyl)peroxydicarbonate, bis(4-t-butylcyclohexyl)peroxydicarbonate, diisopropyl peroxydicarbonate, di-n-propyl peroxydicarbonate, di(2-ethoxyethyl)peroxydicarbonate, and diallyl peroxydicarbonate.

[0064] Among these organic peroxides, from the viewpoint of the overall balance of safety, curability, and storage stability, the chemical polymerization initiator (C-2) is preferably one selected from hydroperoxides and diacyl peroxides, and more preferably a hydroperoxide. Among them, the chemical polymerization initiator (C-2) is preferably one or more selected from the group consisting of benzoyl peroxide, cumene hydroperoxide, t-butyl hydroperoxide, and 1,1,3,3-tetramethylbutyl hydroperoxide, more preferably one or more selected from the group consisting of cumene hydroperoxide, t-butyl hydroperoxide, and 1,1,3,3-tetramethylbutyl hydroperoxide, and even more preferably 1,1,3,3-tetramethylbutyl hydroperoxide.

[0065] The content of the polymerization initiator (C) is not particularly limited, but from the viewpoint of the curability of the dental curable composition, it is preferable that the content of the polymerization initiator (C) be 0.001 to 30 parts by mass per 100 parts by mass of the total amount of the polymerizable monomer (B). By having the content of the polymerization initiator (C) be 0.001 parts by mass or more, polymerization can proceed sufficiently and stickiness can be prevented. From this viewpoint, the content of the polymerization initiator (C) is more preferably 0.03 parts by mass or more, even more preferably 0.05 parts by mass or more, and particularly preferably 0.1 parts by mass or more, per 100 parts by mass of the total amount of the polymerizable monomer (B). On the other hand, by having the content of the polymerization initiator (C) be 30 parts by mass or less, precipitation or separation of the polymerization initiator (C) from the dental curable composition can be prevented. From this viewpoint, the content of the polymerization initiator (C) is more preferably 10 parts by mass or less, even more preferably 5 parts by mass or less, and particularly preferably 2 parts by mass or less, relative to 100 parts by mass of the total amount of the polymerizable monomer (B).

[0066] Furthermore, when the polymerization initiator (C) contains a photopolymerization initiator (C-1), the content of the photopolymerization initiator (C-1) is not particularly limited. However, in one embodiment of the dental curable composition, from the viewpoint of making the effects of the present invention more easily exhibited, the content of the photopolymerization initiator (C-1) in the polymerization initiator (C) is preferably 1 to 40% by mass, more preferably 5 to 30% by mass, and even more preferably 8 to 20% by mass, relative to 100% by mass of the total amount of the polymerization initiator (C).

[0067] Furthermore, when the polymerization initiator (C) contains a chemical polymerization initiator (C-2), the content of the chemical polymerization initiator (C-2) is not particularly limited. However, in one embodiment of the dental curable composition, from the viewpoint of making the effects of the present invention more easily exhibited, the content of the chemical polymerization initiator (C-2) in the polymerization initiator (C) is preferably 60 to 100% by mass, more preferably 70 to 100% by mass, and even more preferably 80 to 100% by mass, relative to 100% by mass of the total amount of the polymerization initiator (C).

[0068] <Polymerization Accelerator (D)> The dental curable composition preferably further contains a polymerization accelerator (D). Examples of the polymerization accelerator (D) include amines, sulfinic acid and its salts, sulfites, bisulfites, aldehydes, thiourea compounds, organic phosphorus compounds, borate compounds, barbituric acid and its derivatives, triazine compounds, vanadium compounds, copper compounds, tin compounds, cobalt compounds, halogen compounds, and thiol compounds. These may be used alone or in combination of two or more. In a preferred embodiment, the dental curable composition includes one or more polymerization accelerators selected from the group consisting of amines, sulfinic acid and its salts, sulfites, bisulfites, aldehydes, thiourea compounds, organic phosphorus compounds, barbituric acid and its derivatives, triazine compounds, vanadium compounds, copper compounds, tin compounds, cobalt compounds, halogen compounds, and thiol compounds. Another preferred embodiment is a dental curable composition comprising glass (A), a polymerizable monomer (B), a polymerization initiator (C), and a polymerization accelerator (D), and substantially no polyacid, wherein the glass (A) comprises strontium, zinc, boron, and fluorine, and wherein the strontium content is 8 to 33 mass %, the zinc content is 2.0 to 25 mass %, the boron content is 1.0 to 11 mass %, the fluorine content is 9 to 35 mass %, and the sodium content is 0 to 0.5 mass %, expressed in mass % for the entire glass (A), and the polymerization initiator (C) comprises a chemical polymerization initiator (C-2).

[0069] Amines 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, N-n-butyldiethanolamine, N-lauryldiethanolamine, 2-(dimethylamino)ethyl methacrylate, N-methyldiethanolamine dimethacrylate, N-ethyldiethanolamine dimethacrylate, triethanolamine monomethacrylate, triethanolamine dimethacrylate, triethanolamine trimethacrylate, triethanolamine, trimethylamine, triethylamine, and tributylamine.

[0070] 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-di-isopropylaniline, N,N-bis(2-hydroxyethyl)-3,5-di-t-butylaniline, N,N-dimethylaniline, N,N-dimethyl-p-toluidine, and N,N-dimethyl-m-toluidine. , N,N-diethyl-p-toluidine, N,N-dimethyl-3,5-dimethylaniline, N,N-dimethyl-3,4-dimethylaniline, N,N-dimethyl-4-ethylaniline, N,N-dimethyl-4-isopropylaniline, N,N-dimethyl-4-t-butylaniline, N,N-dimethyl-3,5-di-t-butylaniline, ethyl 4-(N,N-dimethylamino)benzoate, methyl 4-(N,N-dimethylamino)benzoate, n-butoxyethyl 4-(N,N-dimethylamino)benzoate, 2-(methacryloyloxy)ethyl 4-(N,N-dimethylamino)benzoate, 4-(N,N-dimethylamino)benzophenone, butyl 4-(N,N-dimethylamino)benzoate, and the like. Among these, from the viewpoint of imparting excellent curability to the dental curable composition, 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.

[0071] Examples of sulfinic acid and its salts include p-toluenesulfinic acid, sodium p-toluenesulfinate, potassium p-toluenesulfinate, lithium p-toluenesulfinate, calcium p-toluenesulfinate, benzenesulfinic acid, sodium benzenesulfinate, potassium benzenesulfinate, lithium benzenesulfinate, calcium benzenesulfinate, 2,4,6-trimethylbenzenesulfinic acid, sodium 2,4,6-trimethylbenzenesulfinate, potassium 2,4,6-trimethylbenzenesulfinate, lithium 2,4,6-trimethylbenzenesulfinate, and 2,4,6-trimethylbenzenesulfinic acid. Examples thereof include calcium sulfinate, 2,4,6-triethylbenzenesulfinic acid, sodium 2,4,6-triethylbenzenesulfinate, potassium 2,4,6-triethylbenzenesulfinate, lithium 2,4,6-triethylbenzenesulfinate, calcium 2,4,6-triethylbenzenesulfinate, 2,4,6-triisopropylbenzenesulfinic acid, sodium 2,4,6-triisopropylbenzenesulfinate, potassium 2,4,6-triisopropylbenzenesulfinate, lithium 2,4,6-triisopropylbenzenesulfinate, and calcium 2,4,6-triisopropylbenzenesulfinate.

[0072] Examples of sulfites and bisulfites include sodium sulfite, potassium sulfite, calcium sulfite, ammonium sulfite, sodium bisulfite, potassium bisulfite, etc. Examples of aldehydes include terephthalaldehyde and benzaldehyde derivatives, etc. Examples of benzaldehyde derivatives include dimethylaminobenzaldehyde, p-methoxybenzaldehyde, p-ethoxybenzaldehyde, p-n-octyloxybenzaldehyde, etc.

[0073] Examples of the thiourea compound 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, 4,4-dimethylethylenethiourea, etc. Among these, at least one selected from the group consisting of 1-(2-pyridyl)-2-thiourea and 4,4-dimethylethylenethiourea is preferred from the viewpoint of the curability of the dental curable composition.

[0074] Examples of the organic phosphorus compound include triphenylphosphine, 2-methyltriphenylphosphine, 4-methyltriphenylphosphine, 2-methoxytriphenylphosphine, 4-methoxytriphenylphosphine, tri-n-butylphosphine, triisobutylphosphine, and tri-t-butylphosphine.

[0075] The borate compound is preferably an aryl borate compound. Specific examples of the aryl borate compound that can be suitably used include borate compounds having one aryl group per molecule, such as trialkylphenylboron, trialkyl(p-chlorophenyl)boron, trialkyl(p-fluorophenyl)boron, trialkyl[3,5-bis(trifluoromethyl)phenyl]boron, trialkyl[3,5-bis(1,1,1,3,3,3-hexafluoro-2-methoxy-2-propyl)phenyl]boron, trialkyl(p-nitrophenyl)boron, trialkyl(m-nitrophenyl)boron, trialkyl(p-butylphenyl)boron, trialkyl(m-butylphenyl)boron, trialkyl Examples thereof include (p-butyloxyphenyl)boron, trialkyl(m-butyloxyphenyl)boron, trialkyl(p-octyloxyphenyl)boron, and trialkyl(m-octyloxyphenyl)boron (wherein the alkyl group is at least one selected from the group consisting of an n-butyl group, an n-octyl group, an n-dodecyl group, and the like), as well as salts thereof (sodium salt, lithium salt, potassium salt, magnesium salt, tetrabutylammonium salt, tetramethylammonium salt, tetraethylammonium salt, methylpyridinium salt, ethylpyridinium salt, butylpyridinium salt, methylquinolinium salt, ethylquinolinium salt, butylquinolinium salt, and the like).

[0076] Examples of borate compounds having two aryl groups in one molecule include dialkyldiphenylboron, dialkyldi(p-chlorophenyl)boron, dialkyldi(p-fluorophenyl)boron, dialkyldi[3,5-bis(trifluoromethyl)phenyl]boron, dialkyldi[3,5-bis(1,1,1,3,3,3-hexafluoro-2-methoxy-2-propyl)phenyl]boron, dialkyldi(p-nitrophenyl)boron, dialkyldi(m-nitrophenyl)boron, dialkyldi(p-butylphenyl)boron, dialkyldi(m-butylphenyl)boron, and dialkyldi(p-butyloxyphenyl)boron. Examples of the alkyl group include borane, dialkyldi(m-butyloxyphenyl)borane, dialkyldi(p-octyloxyphenyl)borane, and dialkyldi(m-octyloxyphenyl)borane (wherein the alkyl group is at least one selected from the group consisting of an n-butyl group, an n-octyl group, an n-dodecyl group, and the like), and salts thereof (such as sodium salts, lithium salts, potassium salts, magnesium salts, tetrabutylammonium salts, tetramethylammonium salts, tetraethylammonium salts, methylpyridinium salts, ethylpyridinium salts, butylpyridinium salts, methylquinolinium salts, ethylquinolinium salts, and butylquinolinium salts).

[0077] Examples of borate compounds having three aryl groups in one molecule include monoalkyltriphenylboron, monoalkyltri(p-chlorophenyl)boron, monoalkyltri(p-fluorophenyl)boron, monoalkyltri[3,5-bis(trifluoromethyl)phenyl]boron, monoalkyltri[3,5-bis(1,1,1,3,3,3-hexafluoro-2-methoxy-2-propyl)phenyl]boron, monoalkyltri(p-nitrophenyl)boron, monoalkyltri(m-nitrophenyl)boron, monoalkyltri(p-butylphenyl)boron, monoalkyltri(m-butylphenyl)boron, monoalkyltri(p-butylphenyl)boron, and monoalkyltri(m-butyloxyphenyl)boron, monoalkyltri(p-octyloxyphenyl)boron, monoalkyltri(m-octyloxyphenyl)boron, and monoalkyltri(m-octyloxyphenyl)boron (wherein the alkyl group is one selected from an n-butyl group, an n-octyl group, an n-dodecyl group, or the like), as well as salts thereof (sodium salt, lithium salt, potassium salt, magnesium salt, tetrabutylammonium salt, tetramethylammonium salt, tetraethylammonium salt, methylpyridinium salt, ethylpyridinium salt, butylpyridinium salt, methylquinolinium salt, ethylquinolinium salt, butylquinolinium salt, and the like).

[0078] Examples of borate compounds having four aryl groups in one molecule include tetraphenylboron, tetrakis(p-chlorophenyl)boron, tetrakis(p-fluorophenyl)boron, tetrakis[3,5-bis(trifluoromethyl)phenyl]boron, tetrakis[3,5-bis(1,1,1,3,3,3-hexafluoro-2-methoxy-2-propyl)phenyl]boron, tetrakis(p-nitrophenyl)boron, tetrakis(m-nitrophenyl)boron, tetrakis(p-butylphenyl)boron, tetrakis(m-butylphenyl)boron, tetrakis(p-butyloxyphenyl)boron, tetrakis(m-butyloxyphenyl)boron, tetrakis(p-octyloxyphenyl)boron, tetrakis(m-octyloxyphenyl)boron,

[0033] Examples of suitable aryloxyphenyls include (p-nitrophenyl)triphenylboron, (p-nitrophenyl)triphenylboron, (m-butyloxyphenyl)triphenylboron, (p-butyloxyphenyl)triphenylboron, (m-octyloxyphenyl)triphenylboron, and (p-octyloxyphenyl)triphenylboron, as well as salts thereof (such as sodium salts, lithium salts, potassium salts, magnesium salts, tetrabutylammonium salts, tetramethylammonium salts, tetraethylammonium salts, methylpyridinium salts, ethylpyridinium salts, butylpyridinium salts, methylquinolinium salts, ethylquinolinium salts, and butylquinolinium salts).

[0079] Among these aryl borate compounds, it is more preferable to use a borate compound having three or four aryl groups in one molecule from the viewpoint of storage stability. Furthermore, these aryl borate compounds may be used alone or in combination of two or more.

[0080] Examples of barbituric acids and their derivatives include barbituric acid, 1,3-dimethylbarbituric acid, 1,3-diphenylbarbituric acid, 1,5-dimethylbarbituric acid, 5-butylbarbituric acid, 5-ethylbarbituric acid, 5-isopropylbarbituric acid, 5-cyclohexylbarbituric acid, 1,3,5-trimethylbarbituric acid, 1,3-dimethyl-5-ethylbarbituric acid, 1,3-dimethyl-5-n-butylbarbituric acid, 1,3-dimethyl-5-isobutylbarbituric acid, 1,3-dimethyl-5-cyclopentylbarbituric acid, 1,3-dimethyl-5-cyclohexylbarbituric acid, 1,3-dimethyl-5-phenylbarbituric acid, and 1-cyclohexyl-1-ethylbarbituric acid. barbituric acid, 1-benzyl-5-phenylbarbituric acid, 5-methylbarbituric acid, 5-propylbarbituric acid, 1,5-diethylbarbituric acid, 1-ethyl-5-methylbarbituric acid, 1-ethyl-5-isobutylbarbituric acid, 1,3-diethyl-5-butylbarbituric acid, 1-cyclohexyl-5-methylbarbituric acid, 1-cyclohexyl-5-ethylbarbituric acid, 1-cyclohexyl-5-octylbarbituric acid, 1-cyclohexyl-5-hexylbarbituric acid, 5-butyl-1-cyclohexylbarbituric acid, 1-benzyl-5-phenylbarbituric acid, and thiobarbituric acids, as well as salts thereof (particularly preferred are salts of alkali metals or alkaline earth metals). Examples of the salts of these barbituric acids include sodium 5-butylbarbiturate, sodium 1,3,5-trimethylbarbiturate, sodium 1-cyclohexyl-5-ethylbarbiturate, and the like.

[0081] Examples of the triazine compound include 2,4,6-tris(trichloromethyl)-s-triazine, 2,4,6-tris(tribromomethyl)-s-triazine, 2-methyl-4,6-bis(trichloromethyl)-s-triazine, 2-methyl-4,6-bis(tribromomethyl)-s-triazine, 2-phenyl-4,6-bis(trichloromethyl)-s-triazine, 2-(p-methoxyphenyl)-4,6-bis(trichloromethyl)-s-triazine, and 2-(p-methylthiophenyl)-4,6-bis(trichloromethyl)-s-triazine. 2-(p-chlorophenyl)-4,6-bis(trichloromethyl)-s-triazine, 2-(2,4-dichlorophenyl)-4,6-bis(trichloromethyl)-s-triazine, 2-(p-bromophenyl)-4,6-bis(trichloromethyl)-s-triazine, 2-(p-tolyl)-4,6-bis(trichloromethyl)-s-triazine, 2-n-propyl-4,6-bis(trichloromethyl)-s-triazine, 2-(α,α,β-trichloroethyl)-4,6-bis(trichloromethyl)-s-triazine, 2-styryl-4,6-bis (trichloromethyl)-s-triazine, 2-[2-(p-methoxyphenyl)ethenyl]-4,6-bis(trichloromethyl)-s-triazine, 2-[2-(o-methoxyphenyl)ethenyl]-4,6-bis(trichloromethyl)-s-triazine, 2-[2-(p-butoxyphenyl)ethenyl]-4,6-bis(trichloromethyl)-s-triazine, 2-[2-(3,4-dimethoxyphenyl)ethenyl]-4,6-bis(trichloromethyl)-s-triazine, 2-[2-(3,4,5-trimethoxyphenyl)ethenyl]-4,6 -bis(trichloromethyl)-s-triazine, 2-(1-naphthyl)-4,6-bis(trichloromethyl)-s-triazine, 2-(4-biphenylyl)-4,6-bis(trichloromethyl)-s-triazine, 2-[2-{N,N-bis(2-hydroxyethyl)amino}ethoxy]-4,6-bis(trichloromethyl)-s-triazine, 2-[2-{N-hydroxyethyl-N-ethylamino}ethoxy]-4,6-bis(trichloromethyl)-s-triazine, 2-[2-{N-hydroxyethyl-N-methylamino}ethoxy]-4,6-bis(trichloromethyl)-s-triazine, 2-[2-{N-hydroxyethyl-N-methylamino}ethoxy]-4,6-bis(trichloromethyl)-s-triazine, 2-[2-{N,N-diallylamino}ethoxy]-4,6-bis(trichloromethyl)-s-triazine, etc.

[0082] The vanadium compound is preferably a tetravalent and / or pentavalent vanadium compound. Examples of the tetravalent and / or pentavalent vanadium compound include divanadium(IV) tetroxide, vanadyl acetylacetonate(IV), vanadyl oxalate(IV), vanadyl sulfate(IV), oxobis(1-phenyl-1,3-butanedionato)vanadium(IV), bis(maltolate)oxovanadium(IV), vanadium(V) pentoxide, sodium metavanadate(V), and ammonium metavanadate(V). Among these, vanadyl acetylacetonate(IV) is preferably used from the viewpoint of the hardenability of the dental hardenable composition.

[0083] Examples of copper compounds include copper acetylacetonate, copper (II) acetate, copper oleate, copper (II) chloride, copper (II) bromide, etc. Among these, at least one selected from the group consisting of copper acetylacetonate and copper (II) acetate is preferably used from the viewpoint of the hardenability of the dental hardenable composition.

[0084] Examples of tin compounds include di-n-butyltin dimaleate, di-n-octyltin dimaleate, di-n-octyltin dilaurate, di-n-butyltin dilaurate, etc. Among these, at least one selected from the group consisting of di-n-octyltin dilaurate and di-n-butyltin dilaurate is preferably used. Examples of cobalt compounds include cobalt acetylacetonate, cobalt acetate, cobalt oleate, cobalt chloride, and cobalt bromide.

[0085] Suitable examples of halogen compounds include dilauryldimethylammonium chloride, lauryldimethylbenzylammonium chloride, benzyltrimethylammonium chloride, tetramethylammonium chloride, benzyldimethylcetylammonium chloride, and dilauryldimethylammonium bromide.

[0086] Examples of the thiol compound include 3-mercaptopropyltrimethoxysilane, 2-mercaptobenzoxazole, decanethiol, and thiobenzoic acid.

[0087] Among these polymerization accelerators (D), at least one selected from the group consisting of amines, thiourea compounds, vanadium compounds, and copper compounds is more preferably used, and among these, at least one selected from the group consisting of 1-(2-pyridyl)-2-thiourea, N,N-di(2-hydroxyethyl)-p-toluidine, ethyl 4-(N,N-dimethylamino)benzoate, 4,4-dimethylethylenethiourea, vanadyl acetylacetonate (IV), copper acetylacetonate, and cupric acetate is even more preferably used as the polymerization accelerator (D).

[0088] The content of the polymerization accelerator (D) in the dental curable composition is not particularly limited. However, from the viewpoint of the curability of the dental curable composition, the content of the polymerization accelerator (D) is preferably 0.001 to 30 parts by mass per 100 parts by mass of the total amount of polymerizable monomer (B). By having the content of the polymerization accelerator (D) be 0.001 parts by mass or more, polymerization can proceed sufficiently and stickiness can be prevented. From this viewpoint, the content of the polymerization accelerator (D) is more preferably 0.05 parts by mass or more, even more preferably 0.1 parts by mass or more, and particularly preferably 0.3 parts by mass or more per 100 parts by mass of the total amount of polymerizable monomer (B). On the other hand, by having the content of the polymerization accelerator (D) be 30 parts by mass or less, precipitation of the polymerization accelerator (D) from the dental curable composition can be prevented. From this viewpoint, the content of the polymerization accelerator (D) is more preferably 20 parts by mass or less, even more preferably 10 parts by mass or less, and particularly preferably 5.0 parts by mass or less, relative to 100 parts by mass of the total amount of the polymerizable monomer (B).

[0089] The dental hardenable composition preferably contains substantially no polyacid. Examples of polyacids include polycarboxylic acids, polyphosphoric acids, polyphosphonic acids, polysulfonic acids, polyboric acids, polyacrylic acids, polymaleic acids, and polyvinylphosphonic acids. In this specification, "containing substantially no polyacid" means that the content of polyacid in the dental hardenable composition (100% by mass) is less than 5% by mass, preferably less than 1% by mass, more preferably less than 0.1% by mass, even more preferably less than 0.01% by mass, and particularly preferably 0% by mass.

[0090] The dental curable composition is preferably provided as a kit in the form of a two-material package containing a first material and a second material. In this case, the dental curable composition is more preferably provided as a kit in the form of a two-paste package, in which both the first material and the second material are paste-like. When the dental curable composition is provided as a kit in the form of a two-paste package, the pastes are stored in a state where they are isolated from each other, and the two pastes are mixed together immediately before use to allow chemical polymerization to proceed. Furthermore, when the dental curable composition further contains a photopolymerization initiator (C-1), it is preferable to allow photopolymerization to proceed in addition to chemical polymerization to harden the dental curable composition.

[0091] In the present invention, the chemical polymerization initiator (C-2) and the polymerization accelerator (D) may be combined to form a redox polymerization initiator. In this case, from the viewpoint of storage stability, the chemical polymerization initiator (C-2) and the polymerization accelerator (D) are preferably stored in separate containers. In this case, the dental curable composition is preferably provided as a dental curable composition that is packaged into at least a first material containing the chemical polymerization initiator (C-2) and a second material containing the polymerization accelerator (D).

[0092] <Filler (F)> The dental curable composition preferably further contains a filler (F) other than the glass (A) from the viewpoints of adjusting the paste properties of the dental curable composition before curing, imparting X-ray contrast properties to the cured product, or further improving the strength of the cured product. Examples of fillers that can be used as the filler (F) include organic fillers, inorganic fillers, and organic-inorganic composite fillers. One type of filler (F) may be used alone, or two or more types may be used in combination.

[0093] Examples of organic filler materials include polymethyl methacrylate, polyethyl methacrylate, methyl methacrylate-ethyl methacrylate copolymer, cross-linked polymethyl methacrylate, cross-linked polyethyl methacrylate, polyester, polyamide, polycarbonate, polyphenylene ether, polyoxymethylene, polyvinyl chloride, polystyrene, polyethylene, polypropylene, chloroprene rubber, nitrile rubber, ethylene-vinyl acetate copolymer, styrene-butadiene copolymer, acrylonitrile-styrene copolymer, acrylonitrile-styrene-butadiene copolymer, etc. These may be used alone or in combination of two or more. The shape of the organic filler is not particularly limited, and amorphous fillers, spherical fillers, etc. can be appropriately selected and used, and the particle size of the filler can be appropriately selected and used.

[0094] Examples of inorganic filler materials include quartz, silica, alumina, silica-titania, silica-titania-barium oxide, silica-zirconia, silica-alumina, lanthanum glass, borosilicate glass, soda glass, barium glass, strontium glass, glass ceramic, aluminosilicate glass, barium boroaluminosilicate glass, and strontium boroaluminosilicate glass. These may also be used alone or in combination of two or more. The shape of the inorganic filler is not particularly limited, and irregular fillers, spherical fillers, and the like can be appropriately selected and used, and the particle size of the filler can also be appropriately selected and used.

[0095] The inorganic filler may be surface-treated in advance with a known surface treatment agent such as a silane coupling agent, if necessary, to adjust the miscibility with components (A) and (B). Examples of such surface treatment agents include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltrichlorosilane, vinyltri(β-methoxyethoxy)silane, 3-methacryloyloxypropyltrimethoxysilane, 11-methacryloyloxyundecyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, and 3-aminopropyltriethoxysilane.

[0096] The surface treatment method can be any known method without any particular limitation, and examples thereof include a method in which the surface treatment agent is sprayed onto the inorganic filler while vigorously stirring it; a method in which the inorganic filler and the surface treatment agent are dispersed or dissolved in a suitable solvent, and then the solvent is removed; and a method in which the alkoxy groups of the surface treatment agent are hydrolyzed in an aqueous solution with an acid catalyst to convert them into silanol groups, which are then attached to the surface of the inorganic filler in the aqueous solution, and then the water is removed. In any of these methods, the reaction between the surface of the inorganic filler and the surface treatment agent can be completed and the surface treatment can be performed by heating, typically within a range of 50 to 150°C.

[0097] The organic-inorganic composite filler is obtained by adding a monomer compound (e.g., polymerizable monomer (B)) to the inorganic filler described above, forming a paste, polymerizing the mixture, and pulverizing it. As the organic-inorganic composite filler, for example, TMPT filler (trimethylolpropane trimethacrylate and silica filler are mixed, polymerized, and then pulverized) can be used. The shape of the organic-inorganic composite filler is not particularly limited, and irregular fillers, spherical fillers, etc. can be appropriately selected and used, and the particle size of the filler can be appropriately selected and used.

[0098] From the viewpoints of the handleability of the dental curable composition and the mechanical strength and transparency of the cured product thereof, the average primary particle diameter of the filler (F) is preferably 0.001 to 10 μm, more preferably 0.005 to 5.0 μm, even more preferably 0.01 to 4.0 μm, and particularly preferably 0.04 to 3.0 μm. In this specification, the average primary particle diameter of the filler (F) can be determined by observation with an optical microscope or an electron microscope. Specifically, optical microscope observation is convenient for measuring particle diameters of 100 nm or more, while electron microscope observation is convenient for measuring particle diameters of less than 100 nm.

[0099] The content of the filler (F) is not particularly limited, but from the viewpoint of the handleability of the dental curable composition and the strength of the cured product thereof, the total amount of the glass (A) and the filler (F) relative to 100 parts by mass of the total amount of the polymerizable monomer (B) is preferably 30 parts by mass or more, more preferably 40 parts by mass or more, and even more preferably 50 parts by mass or more, and is preferably 1,000 parts by mass or less, more preferably 900 parts by mass or less, and even more preferably 850 parts by mass or less.

[0100] When the filler (F) is contained, the amount of the filler (F) is preferably 0.001 to 10 parts by mass, more preferably 0.005 to 5 parts by mass or more, and even more preferably 0.1 to 3 parts by mass, per 100 parts by mass of the glass (A).

[0101] <Other Additives> In addition, known other additives can be blended into the dental curable composition as needed within the range in which the effects of the present invention are achieved. Examples of other additives include a polymerization inhibitor (E) other than the above-mentioned components, an antioxidant, a pigment, a dye, an ultraviolet absorber, an organic solvent, a thickener, etc. In addition, in this specification, the term "other additives" does not include polymerizable monomers.

[0102] Examples of the polymerization inhibitor (E) include hydroquinone, hydroquinone monomethyl ether, dibutylhydroquinone, dibutylhydroquinone monomethyl ether, t-butylcatechol, 2-t-butyl-4,6-dimethylphenol, 2,6-di-t-butylphenol, 3,5-di-t-butyl-4-hydroxytoluene, etc. When the dental curable composition contains the polymerization inhibitor (E), the content of the polymerization inhibitor (E) is preferably 0.001 to 1.0 part by mass, more preferably 0.005 to 0.5 part by mass, and even more preferably 0.01 to 0.1 part by mass, per 100 parts by mass of the total amount of the polymerizable monomer (B).

[0103] Furthermore, the total amount of other additives in the dental hardenable composition is not particularly limited as long as the effects of the present invention are achieved. However, from the viewpoint of making it easier to achieve the effects of the present invention, the total amount of other additives is preferably 20% by mass or less, more preferably 15% by mass or less, even more preferably 10% by mass or less, particularly preferably 5% by mass or less, and most preferably 2% by mass or less, and is 0% by mass, relative to 100% by mass of the total amount of the dental hardenable composition.

[0104] The dental curable composition is not particularly limited as long as it contains glass (A), a polymerizable monomer (B), a polymerization initiator (C), and, if necessary, a polymerization accelerator (D). However, from the viewpoint of preventing a decrease in strength and water resistance of the cured product, as well as cloudiness, it is preferable that the dental curable composition be substantially free of polycarboxylic acid. In this specification, "substantially free of polycarboxylic acid" refers to the polycarboxylic acid content as described above in the "substantially free of polyacid" section. In addition, from the viewpoint of improving the strength and color tone of the resulting cured product, it is preferable that the dental curable composition be substantially free of water. In this specification, "substantially free of water" means that the water content is 5.0% by mass or less, preferably 1.0% by mass or less, more preferably 0.5% by mass or less, even more preferably 0.1% by mass or less, and particularly preferably 0.05% by mass or less, based on 100% by mass of the total amount of the dental curable composition.

[0105] The dental hardenable composition has excellent ion release properties and mechanical strength after curing. Therefore, the dental hardenable composition can be suitably used as a dental composite resin that takes advantage of these advantages, and is particularly suitable for use as a dental filling and restorative material, a dental cement, and a dental core buildup material. Furthermore, the dental hardenable composition can be produced by any method known to those skilled in the art without any particular limitations on the method of mixing the components, except for the above-mentioned case where the dental hardenable composition is used in the form of a two-component type consisting of the first material and the second material.

[0106] Next, the present invention will be explained in more detail with reference to examples, but the present invention is not limited to these examples in any way.

[0107] Each component used in the examples and comparative examples will be explained below together with its abbreviation.

[0108] [Manufacturing Example A] [Glass (A)] The corresponding oxides, fluorides, carbonates, nitrates, hydroxides, etc. were prepared as raw materials for each component, and were weighed so that the composition after vitrification would be as shown in column A of Table 1. The mixture was thoroughly mixed and placed in a platinum crucible and melted in an electric furnace. The temperature during melting was adjusted appropriately within the range of 1000 to 1500°C to ensure sufficient degassing. The mixture was then stirred appropriately to homogenize, clarified, and rapidly cooled to obtain glass. However, there were also cases where glass was not obtained. In Table 1, the vitrification item in which glass was obtained is indicated by "G," and the vitrification item in which glass was not obtained is indicated by "NG."

[0109] [Production Examples B to P] Glasses were obtained in the same manner as in Production Example A, except that the component ratios were changed as shown in columns B to P in Table 1. However, in Production Examples H, J, N, and P, crystals precipitated and the glass became devitrified, so that glasses usable as dental hardenable compositions could not be obtained.

[0110] [Hydrophilic (meth)acrylic monomer (B-1) containing two or more (meth)acryloyloxy groups in one molecule] BMHPE: 1,2-bis(3-methacryloyloxy-2-hydroxypropoxy)ethane (manufactured by Shin-Nakamura Chemical Co., Ltd.) GDM: glycerol dimethacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd.)

[0111] [Hydrophobic (meth)acrylic monomer (B-2) containing two or more (meth)acryloyloxy groups in one molecule] UDMA: 2,2,4-trimethylhexamethylenebis(2-carbamoyloxyethyl)dimethacrylate (manufactured by Kyoeisha Chemical Co., Ltd.) Bis-GMA: 2,2-bis[4-(2-hydroxy-3-methacryloyloxypropoxy)phenyl]propane

[0112] [Mono(meth)acrylic monomer (B-3) containing no hydroxyl group, acidic group, amino group or amide group in one molecule] POBMA: m-phenoxybenzyl methacrylate (manufactured by Kyoeisha Chemical Co., Ltd.) LMA: lauryl methacrylate (manufactured by Kyoeisha Chemical Co., Ltd.)

[0113] [Polymerization initiator (C)] <Photopolymerization initiator (C-1)> CQ: camphorquinone BAPO: bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide <Chemical polymerization initiator (C-2)> THP: 1,1,3,3-tetramethylbutyl hydroperoxide

[0114] [Polymerization accelerator (D)] PDE: ethyl 4-N,N-dimethylaminobenzoate VOAA: vanadyl acetylacetonate 2-PyTU: 1-(2-pyridyl)-2-thiourea

[0115] [Polymerization inhibitor (E)] BHT: 3,5-di-t-butyl-4-hydroxytoluene

[0116] [Filler (F)] Ar380: hydrophilic fumed silica "AEROSIL (registered trademark) 380" (manufactured by Nippon Aerosil Co., Ltd., average primary particle size: 0.007 μm)

[0117] <Measurement of Average Particle Diameter of Glass (A)> The glass produced in Table 1 was pulverized in a ball mill to obtain pulverized glass. The average particle diameter of 200 particles of the obtained pulverized glass was measured on a volume basis using a laser diffraction particle size distribution analyzer (manufactured by Shimadzu Corporation, model "SALD-2300") and a 0.2% aqueous solution of sodium hexametaphosphate as a dispersion medium. The results are shown in Table 1.

[0118] <Measurement of refractive index of glass (A)> Using the crushed glass obtained as described above, the refractive index was measured in accordance with the refractive index measurement method of JIS B 7071-2:2018 (Part 2: V-block method). The results are shown in Table 1. From the viewpoint of aesthetics, a refractive index of glass (A) in the range of 1.500 to 1.600 was considered acceptable. The refractive index of the glass obtained in Production Example O exceeded 1.600, and glass having transparency usable as a dental hardenable composition could not be obtained.

[0119] <Aluminum ion elution amount (W Al ), silicon ion elution amount (W Si ), strontium ion elution amount (W Sr)> A silane-treated glass powder was obtained by forming a layer of a silanol compound on the surface of glass (A) using 100 parts by mass of the pulverized glass obtained as described above, and then subjecting the silanol groups to intermolecular dehydration condensation. Specifically, the surface was treated with 1.5 parts by mass of γ-methacryloyloxypropyltrimethoxysilane by a conventional method, yielding a silane-treated glass powder. The amount of eluted ions and the ratio of eluted ions in the obtained silane-treated glass powder were measured or evaluated as follows. The contents of various ions in the sample were measured using inductively coupled plasma atomic emission spectrometry (ICP-AES) as follows. 250 mg of silane-treated glass powder and 4 mL of distilled water were added to a resin container and stirred at 300 rpm for 24 hours in a 37°C incubator. The solution was centrifuged (10,000 rpm, 5 min, tabletop high-speed microcentrifuge "himac CT15E", manufactured by Hitachi Koki Co., Ltd. (now Koki Holdings Co., Ltd.)). The supernatant was then filtered through a 0.22 μm PTFE (polytetrafluoroethylene) membrane filter to prepare a test solution. Nitric acid and hydrofluoric acid were added to the obtained test solution, and the volume was adjusted to the desired value with ultrapure water to obtain a test solution. The obtained test solution was measured using an ICP atomic emission spectrometer (trade name "Agilent 5110 VDV type", manufactured by Agilent Technologies, Inc.) under the following conditions to measure the concentrations of various ions in the test solution. [Measurement conditions] Photometry mode: Axial Reading time (sec): 20 Number of repetitions: 3 Stabilization time (sec): 15 High-speed pump (rpm): Not set Pump speed (rpm): 12 Output (kW): 1.2 Plasma gas flow rate (L / min): 12 Auxiliary gas flow rate (L / min): 1.0 Nebulizer gas flow rate (L / min): 0.7

[0120] <Eluted ion amount ratio (W Sr ) / (W Al+Si ) > Measured W Al , W Si and W Sr(μg / g) was used to calculate the eluted ion amount ratio (W Sr ) / (W Al+Si When the ratio of the amount of eluted ions is 10 or more, a high demineralization inhibition rate is indicated. Al+Si =W Al +W Si ... (1) Elution ion amount ratio = W Sr / W Al+Si ...(2)

[0121]

[0122] [Examples 1-1 to 1-7, 2-1 to 2-8, 3-1 to 3-2 and Comparative Examples 1-1 to 1-4] The components shown in Tables 2, 3, and 4 were mixed at room temperature (25°C) to prepare pastes, thereby obtaining dental curable compositions for each Example and Comparative Example. The glass used was the silane-treated glass powder obtained as described above. For the kneading of Examples 3-1 to 3-2 consisting of two materials, a polyolefin resin storage container (total internal volume 5 mL, product code "SDL 005-01-SI", manufactured by Sulzer Mixpac AG (Switzerland)) in which a pair of identical cylinders were arranged in parallel, a mixer attached to the tip side of these storage containers, and a pair of cylindrical extrusion members fitted into each storage container from the rear end side. An extrusion device (product code "PED 005-01-SI", manufactured by Sulzer Mixpac AG (Switzerland)) consisting of a kneading device was used. By pushing the extrusion member, an equal volume of paste inside the cylindrical container was collected. The mixer used was a mixing tip (product code "ML 2.5-08-S", manufactured by Sulzer Mixpac AG (Switzerland)) having eight stirring blades (elements). The decalcification inhibition rate, X-ray contrast property and bending strength of the obtained dental curable compositions were measured or evaluated as follows.

[0123] <Decalcification Inhibition Rate> The labial surface of a bovine mandibular anterior tooth was polished under running water with #80 silicon carbide paper (manufactured by Nihon Kenshi Co., Ltd.) to expose a flat surface of the dentin. The exposed flat surface was further polished under running water with #1000 silicon carbide paper (manufactured by Nihon Kenshi Co., Ltd.) to form a polished surface. After polishing, the bovine mandibular anterior tooth was cut into two pieces perpendicular to the polished surface using a diamond cutter, one of which was used as a control and the other as a test specimen. The control tooth was masked with nail polish except for the polished surface measuring 2 mm x 6 mm. A cavity measuring 2 mm x 6 mm x 2 mm in height was formed adjacent to the polished surface measuring 2 mm x 6 mm for the test specimen, and the dental curable composition prepared in the Examples and Comparative Examples was filled into the cavity. After filling, the one-component dental curable compositions shown in Tables 2 and 3 were cured using a dental LED light irradiator (trade name "Pencure 2000", manufactured by Morita Corporation). On the other hand, for the two-component dental curable compositions in Table 4, the first and second components were mixed together to fill the cavity, and the resulting mixture was immersed in a thermostatic water bath at 37°C to accelerate curing. After curing, each test piece was polished again under running water using #1000 silicon carbide paper (manufactured by Nihon Kenshi Co., Ltd.) so that the 2 mm x 6 mm polished surface and the cured product filled in the cavity with a base area of ​​2 mm x 6 mm were flat. Furthermore, the test pieces were masked with nail polish except for the 2 mm x 6 mm polished surface and the surface of the cured dental curable composition, so that if excess ions were released from areas outside the measurement target, the amount of ions released could be excluded from the measurement, thereby improving the accuracy of the measurement. Using the test pieces obtained as described above, the amount of ions was measured using the following method, and the decalcification inhibition rate was calculated.

[0124] The control and test specimens were placed separately in a 12-well polystyrene plate with φ25mm x 17mm wells, with the polished surface facing up. 4 ml of divalent cation-free phosphate buffer PBS(-) was added to each well and allowed to stand in an incubator at 37 ° C for 24 hours. The control and test specimens were then removed, washed with ion-exchanged water, and the moisture was removed. The control and test specimens were then placed separately in a 12-well polystyrene plate with φ25mm x 17mm wells. 4 ml of 0.5 mol / L acetate buffer (pH = 4.6) was added to each well and allowed to stand in an incubator at 37 ° C for 24 hours. The 0.5 mol / L acetate buffer was then recovered from each well. 30 μl of 0.1 mol / L potassium chloride aqueous solution was added as an ionic strength stabilizer to 0.3 ml of the recovered acetate buffer, and the mixture was shaken to obtain a decalcification solution. The calcium ion concentrations of the resulting decalcification solutions were measured using a calcium ion meter (trade name "LAQUA Twin," manufactured by Horiba, Ltd.). The calcium ion concentration of the control was designated M0, and that of the test specimen was designated M1. Next, 300 ml of each solution was diluted with 0.5 mol / L acetate buffer (pH = 4.6) to give calcium ion concentrations of 2.5, 5.0, 10.0, 20.0, and 40.0 mmol / L. 30 μl of 0.1 mol / L potassium chloride aqueous solution was added to each diluted solution. The calcium ion concentrations of these solutions were measured using a calcium ion meter (trade name "LAQUA Twin," manufactured by Horiba, Ltd.). The adjusted calcium ion concentrations (2.5, 5.0, 10.0, 20.0, and 40.0 mmol / L) were plotted on the horizontal axis against the measured calcium ion concentrations on the vertical axis, creating a calibration curve passing through the origin. The slope of the resulting calibration curve is designated "A" in the following equations (3) and (4). The amounts of calcium ions Ca and Ca (μmol / cm) eluted from the following formulas (3) and (4) can be calculated. 2 ) was sought.

[0125] Here, the actual measured area of ​​the polished surface of 2 mm x 6 mm was designated S0 for the control and S1 for the test piece. Amount of dissolved Ca ions (control) Ca0 = (M0 / A) x 4 (ml) / S0 (3) Amount of dissolved Ca ions (test piece) Ca1 = (M1 / A) x 4 (ml) / S1 (4)

[0126] The demineralization inhibition rate was calculated using the determined Ca0 and Ca1 according to the following formula (5): Decalcification inhibition rate (%) = (Ca0 - Ca1) / Ca0 (5)

[0127] <X-ray contrast properties> First, test pieces (φ1.5 mm × 1.0 mm) of the cured products were prepared from the dental curable compositions prepared in the Examples and Comparative Examples according to the formulation as follows. The one-component dental curable compositions in Tables 2 and 3 were cured using a dental LED light irradiator (trade name "PenCure 2000", manufactured by Morita Corporation) to prepare test pieces of the cured products. On the other hand, for the two-component dental curable compositions in Table 4, the mixture obtained by mixing the first and second components was immersed in a thermostatic water bath at 37°C to accelerate curing and cure, to prepare test pieces of the cured products. Next, the test piece was placed next to an aluminum step wedge (control) in the center of an X-ray film (trade name "UltraSpeed ​​Dental Film (occlusal type) DF-50", manufactured by Carestream Health Co., Ltd.), and X-ray irradiation was performed using a digital X-ray imaging device (trade name "Max DC-70", manufactured by Morita Seisakusho Co., Ltd.) under conditions of a target-film distance of 400 mm and a tube voltage of 70 kV. After the film was developed, fixed, and dried, an optical densitometer (trade name "DENSITOMETER PDA-85", manufactured by Konica Minolta, Inc., measurement area (3 mmφ)) was used to measure the image density of the test piece at 20 points, and the image density of the test piece was compared with the image density of each thickness of the aluminum step wedge. The X-ray contrast corresponding to the thickness of the aluminum step wedge was determined (n = 1).

[0128] The X-ray contrast is preferably 1.0 mm or more, more preferably 1.3 mm or more, even more preferably 1.5 mm or more, and may be 2.0 mm or more, or may be 3.0 mm or more. When the X-ray contrast is 1 mm or more, it is rated as "≧1", and when it is less than 1 mm, it is rated as "<1".

[0129] <Flexural strength> Evaluation was performed by a bending test (three-point bending test) in accordance with ISO 4049:2019. The kneaded product of each dental curable composition prepared in the Examples and Comparative Examples was filled into a SUS mold (2 mm long x 2 mm thick x 25 mm long), and the top and bottom were pressed together with glass slides. Next, for the one-component dental curable compositions in Tables 2 and 3, light was irradiated for 10 seconds using a dental LED light irradiator (trade name "PenCure 2000", manufactured by Morita Corporation) to harden the dental curable composition, and then the cured product was removed from the mold and immersed in a thermostatic water bath at 37 ° C. On the other hand, for the two-component dental curable compositions in Table 4, the first and second materials were mixed to obtain a mixture, and then the mixture was filled into the SUS mold and pressed together with glass slides. The product obtained by removing from the mold and pressing was immersed in a thermostatic water bath at 37 ° C. to accelerate curing and obtain a cured product. The immersion periods in the 37°C constant temperature water baths were one day (1d) and one week (1w), respectively. The resulting cured products were subjected to a three-point bending test using a universal testing machine (product name "Autograph (registered trademark) AG-I 100kN", manufactured by Shimadzu Corporation) at a support distance of 20 mm and a crosshead speed of 2 mm / min to measure the flexural strength and flexural modulus (arithmetic mean values ​​for n=5).

[0130] The bending strength (1d) when immersed in a thermostatic water bath at 37°C for one day is preferably 80 MPa or more, more preferably 100 MPa or more, and even more preferably 120 MPa. The bending strength (1w) when immersed in a thermostatic water bath at 37°C for one week is preferably 50 MPa or more, more preferably 80 MPa or more, and even more preferably 100 MPa.

[0131]

[0132]

[0133]

[0134] The results in Tables 2, 3, and 4 confirm that the one-component dental hardenable compositions and two-component dental hardenable compositions of the examples are excellent in decalcification inhibition rate, X-ray contrast property, and bending strength. On the other hand, it was confirmed that Comparative Example 1-3, which contains a large amount of boron, has low bending strength. Furthermore, it was confirmed that Comparative Example 1-1, which contains a small amount of strontium, Comparative Example 1-2, which contains a small amount of zinc, and Comparative Example 1-4, which contains a small amount of boron, have low decalcification inhibition rates.

[0135] The dental curable composition can be suitably used for dental composite resins, dental filling and restorative materials, dental cements, and dental core construction materials, and can be particularly suitably used for dental filling and restorative materials, dental cements, and dental core construction materials.

Claims

1. A dental hardenable composition comprising glass (A), a polymerizable monomer (B), and a polymerization initiator (C), wherein the glass (A) contains strontium, zinc, boron, and fluorine, and wherein the constituent elements of the entire glass (A) are expressed in mass % as follows: the strontium content is 8 to 33 mass %, the zinc content is 2.0 to 25 mass %, the boron content is 1.0 to 11 mass %, the fluorine content is 9 to 35 mass %, and the sodium content is 0 to 0.5 mass %.

2. The dental curable composition according to claim 1, wherein the polymerizable monomer (B) contains a hydrophilic (meth)acrylic monomer (B-1) containing two or more (meth)acryloyloxy groups in one molecule, and a hydrophobic (meth)acrylic monomer (B-2) containing two or more (meth)acryloyloxy groups in one molecule.

3. The dental curable composition according to claim 1 or 2, wherein the polymerizable monomer (B) further contains a mono(meth)acrylic monomer (B-3) containing no hydroxyl group, acidic group, amino group or amide group in one molecule.

4. The dental curable composition according to claim 1 or 2, comprising, based on a total of 100 parts by mass of the polymerizable monomer (B), 5 to 55 parts by mass of a hydrophilic (meth)acrylic monomer (B-1) containing two or more (meth)acryloyloxy groups in one molecule, 25 to 70 parts by mass of a hydrophobic (meth)acrylic monomer (B-2) containing two or more (meth)acryloyloxy groups in one molecule, and 0 to 55 parts by mass of a mono(meth)acrylic monomer (B-3) containing none of a hydroxyl group, an acidic group, an amino group, or an amide group in one molecule.

5. The glass (A) further contains aluminum and silicon, and the silane-treated glass powder obtained by surface-treating 100 parts by mass of the crushed glass of the glass (A) with 1.5 parts by mass of γ-methacryloyloxypropyltrimethoxysilane is immersed in distilled water at 37° C. for 24 hours at a concentration of 5% by mass, and the amount of strontium ion elution (W Sr ) and the sum of the amount of aluminum ions dissolved and the amount of silicon ions dissolved (W Al + Si ) and the ratio (W Sr ) / (W Al+Si 3. The dental hardenable composition according to claim 1, wherein the number of carboxyl groups is 10 or more.

6. The dental hardenable composition of claim 1 or 2, wherein the dental hardenable composition is substantially free of polyacids.

7. The dental hardenable composition according to claim 1 or 2, wherein the polymerization initiator (C) contains a chemical polymerization initiator (C-2).

8. The dental hardenable composition according to claim 1 or 2, further comprising a polymerization accelerator (D).

9. The dental hardenable composition according to claim 1 or 2, wherein the dental hardenable composition is packaged in a first material and a second material.

10. The dental hardenable composition according to claim 9, wherein the first material contains a chemical polymerization initiator (C-2), and the second material contains a polymerization accelerator (D).

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