Dental resin-reinforced glass ionomer cement composition

Abstract

To provide a dental resin-reinforced glass ionomer cement composition that exhibits little stringiness of the kneaded product, is in a state in which shaping operations can be performed soon after the end of kneading, has excellent cavity filling properties and application properties to dental prosthetic devices, and has good kneadability, mechanical properties, and transparency.SOLUTION: Provided is a dental resin-reinforced glass ionomer cement composition, comprising (a) acid-reactive glass powder, (b) polyalkenoic acid, (c) water, (d) polymerizable monomer, (e) porous inorganic filler (1 mass% or more and 15 mass% or less), and (f) a polymerization initiator, the core of the (e) porous inorganic filler being an inorganic particle composed solely of silicon dioxide or composed of silicon dioxide and an oxide containing one or more metal elements.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a dental resin-reinforced glass ionomer cement composition for filling and restoring teeth whose shape has been partially damaged, mainly due to caries or fractures, or for bonding or luting dental prosthetic devices to teeth whose shape has been damaged. [Background technology]

[0002] In clinical dentistry, direct restoration, in which filling materials are placed in the teeth, and indirect restoration, in which dental prostheses are bonded and / or adhered to the teeth using adhesive materials, are used to restore the aesthetic and functional appearance of teeth that have been partially damaged by caries, fractures, etc. Dental resin-reinforced glass ionomer cement is one of the most common filling and adhesive materials.

[0003] Dental resin-reinforced glass ionomer cements are primarily composed of acid-reactive glass powders, typically fluoroaluminosilicate glass powders, polyalkenoic acid, water, polymerizable monomers, and polymerization initiators. They are typically available in two-component forms, such as powder-liquid or two-paste. These types of dental resin-reinforced glass ionomer cements are prepared immediately before use by hand or mechanical mixing (powder-liquid types) or by hand or automatic mixing using a mixing tip (two-paste types). Dental resin-reinforced glass ionomer cements mixed in this manner undergo an acid-base reaction between the polyalkenoic acid and acid-reactive glass powder, as well as the initiation of a chemical polymerization reaction of the polymerizable monomer, leading to curing. Some types also allow for photopolymerization by adding a photoinitiator.

[0004] Dental resin-reinforced glass ionomer cements are characterized by their ability to sustain the release of fluoride ions over a long period of time, as well as their high transparency and mechanical properties. Furthermore, when photocuring is added, the composition can be cured by irradiating light at the timing intended by the surgeon, eliminating the need to wait for curing.

[0005] Patent Document 1 discloses a technology in which a tri- or higher functional (meth)acrylamide polymerizable monomer is further added to the general main component of the aforementioned dental resin-reinforced glass ionomer cement, thereby achieving high surface hardening properties even when wet, excellent color resistance, and low water absorption expansion. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent Publication No. 2021-031409 Summary of the Invention [Problem to be solved by the invention]

[0007] Dental resin-reinforced glass ionomer cements contain a highly viscous aqueous solution of polyalkenoic acid in their composition, and therefore tend to become stringy immediately after mixing. This stringiness can adversely affect operability during filling and cementation, and is particularly susceptible to this effect during filling operations. For example, after filling the mixture immediately after mixing with a dental instrument such as a dental syringe or other dental tool, if the mixture becomes stringy when the dental tool is removed from the mixture, the mixture may adhere to the surrounding tooth structure or oral mucosa. In such cases, the adhesions must be carefully removed, making the process complicated.

[0008] In addition, since dental resin-reinforced glass ionomer cement begins to harden immediately after mixing due to the acid-base reaction and chemical polymerization, the stringiness of the mixed material decreases after a certain period of time, regardless of the properties of the mixed material, making it easier to perform the shaping operation. Therefore, when shaping the mixed material filled into the cavity, the shaping operation is performed after waiting until the stringiness of the mixed material decreases. On the other hand, if the mixed material is significantly stringy and it takes a long time for the stringiness to decrease, the treatment time will be longer and the risk of the treatment site being contaminated by saliva will increase.

[0009] Methods for reducing stringiness of the mixed material immediately after mixing include increasing the proportion of acid-reactive glass powder contained in the dental resin-reinforced glass ionomer cement or increasing the particle size. However, increasing the proportion of acid-reactive glass powder increases the viscosity of the mixed material, which may result in poor mixing. Furthermore, increasing the particle size of the acid-reactive glass powder may reduce the acid-base reactivity of the acid-reactive glass powder and polyalkenoic acid, which may result in a decrease in the mechanical properties of the cured product.

[0010] Therefore, an object of the present invention is to provide a dental resin-reinforced glass ionomer cement composition which exhibits less stringiness of the kneaded product than conventional techniques, has excellent cavity filling properties and application properties to dental prosthetic devices, and is ready for shaping operations soon after kneading, while also exhibiting good kneadability, mechanical properties, and transparency. [Means for solving the problem]

[0011] As a result of intensive research conducted to address these challenges, the present inventors have found that by incorporating a specific porous inorganic filler in a dental resin-reinforced glass ionomer cement composition in a specific range, the kneaded product has less stringiness, excellent cavity filling properties and excellent applicability to dental prosthetic devices, and is in a state where shaping operations can be performed quickly after kneading is complete, while also exhibiting good kneading properties and excellent mechanical properties and good transparency. Furthermore, the present inventors have found that a dental resin-reinforced glass ionomer cement composition that further contains an organic-inorganic composite filler in addition to the specific porous inorganic filler, with the total content and content ratio of these fillers within specific ranges, can maintain a low viscosity of the kneaded product and further improve kneading properties, thereby completing the present invention.

[0012] That is, the above problems are solved by the present invention described below. (a) acid-reactive glass powder; (b) polyalkenoic acid, (c) water; (d) a polymerizable monomer; (e) porous inorganic filler: 1% by mass or more and 15% by mass or less; and (f) a polymerization initiator, A dental resin-reinforced glass ionomer cement composition comprising: A dental resin-reinforced glass ionomer cement composition characterized in that the center of the (e) porous inorganic filler is an inorganic particle composed only of silicon dioxide, or composed of silicon dioxide and an oxide containing one or more metal elements. [Effects of the Invention]

[0013] According to the present invention, it is possible to provide a dental resin-reinforced glass ionomer cement composition that exhibits little stringiness immediately after mixing, thereby providing excellent cavity filling properties and excellent application properties to dental prosthetic devices, and that is capable of shortening treatment time because it is ready for shaping operations soon after mixing is completed, while also exhibiting good mixability, mechanical properties, and transparency. DETAILED DESCRIPTION OF THE INVENTION

[0014] In the present invention, the porous inorganic filler (e) has a 50% particle diameter (D50) of 0.1 μm or more and 10 μm or less, a pore volume of 0.01 cc / g or more and 1.00 cc / g or less, and a specific surface area of ​​5 m 2 / g or more 500m 2 / g or less.

[0015] In the present invention, the composition further comprises (g) an organic-inorganic composite filler, and the (g) organic-inorganic composite filler has a 50% particle size (D50) in the range of 1 μm or more and 50 μm or less, and can contain 10% by mass or more and 85% by mass or less of an inorganic filler having a 50% particle size (D50) of 0.005 μm or more and 3 μm or less.

[0016] In the present invention, the total content of the (e) porous inorganic filler and the (g) organic-inorganic composite filler is 2% by mass or more and 20% by mass or less with respect to the entire composition, and The mass ratio of the content of the (e) porous inorganic filler to the content of the (g) organic-inorganic composite filler [(g) organic-inorganic composite filler / (e) porous inorganic filler] may be 0.5 or more and 2.5 or less.

[0017] In the present invention, the (a) acid-reactive glass powder is 30% by mass or more and 80% by mass or less, the (b) polyalkenoic acid is 0.5% by mass or more and 17% by mass or less; (c) Water 0.5% by mass or more and 27% by mass or less, and the (d) polymerizable monomer is 2% by mass or more and 48% by mass or less; may include:

[0018] In the present invention, the time required for starting shaping of the dental resin-reinforced glass ionomer cement composition can be 40 seconds or less.

[0019] The present invention will be described in detail below. As used herein, the term "dental resin-reinforced glass ionomer cement composition" refers to a dental material that hardens through a polymerization reaction of a compound having a polymerizable group, such as a polymerizable monomer, an oligomer having a polymerizable group, and / or a polymer having a polymerizable group, and through an acid-base reaction that occurs between an acid-reactive glass powder and a polyalkenoic acid in the presence of water.

[0020] In this specification, the degree of stringiness of the kneaded material was evaluated by the following method. Specifically, a kneaded dental resin-reinforced glass ionomer cement composition (defined as a total amount of 360 mg) was filled into a simulated cavity of a certain size, the excess was scraped off to make the surface flat, and 10 seconds after the end of kneading, the cylindrical tip of a metal instrument (diameter: φ1.5 mm) was immersed vertically 0.5 mm into the kneaded material, and the degree of stringiness was confirmed when the instrument was immediately gently pulled up. This test was performed in an environment with a temperature of 23±1°C and a humidity of 50±10%. If the kneaded material did not string, or if there was only slight stringiness, it was judged to have "good kneaded material properties with little stringiness."

[0021] In addition, the degree of stringiness of the kneaded product was evaluated using the same method, and the time from the end of kneading until the stringiness of the kneaded product reduced and it became possible to perform shaping operations was defined as the ``time until shaping can begin.''

[0022] In this specification, the "contrast ratio" is a measure of transparency expressed as a numerical value between 0 and 1, with the closer to 0 the transparency, the higher the transparency, and the closer to 1 the transparency, the lower the transparency. The contrast ratio is calculated by measuring the Y value (Yw) on a white plate and the Y value (Yb) on a black plate using a colorimeter for a 1 mm thick cured product, and determining the ratio (Yb / Yw) of these values.

[0023] In this specification, the term "polyalkenoic acid" refers to a polymer containing an ethylenically unsaturated monomer unit having an acidic group. In addition, in this specification, (meth)acrylate refers to both acrylate and methacrylate, (meth)acryloyl refers to both acryloyl and methacryloyl, (meth)acrylic acid refers to both acrylic acid and methacrylic acid, and (meth)acrylamide refers to both acrylamide and methacrylamide.

[0024] In addition, in this specification, the term "50% particle size (D50)" refers to the particle size at which the cumulative value from the small particle size side reaches 50% in a volume-based particle size distribution measured using a laser diffraction / scattering particle size distribution analyzer.

[0025] In addition, in this specification, the term "pore volume" refers to a value determined by the BJH method from an adsorption isotherm obtained by a nitrogen adsorption method.

[0026] In this specification, the term "specific surface area" refers to a value determined by the BET method from an adsorption isotherm obtained by a nitrogen adsorption method.

[0027] The dental resin-reinforced glass ionomer cement composition of the present invention can be used, for example, in a kneading device for capsules for tooth restorative materials, or in a capsule for mixing and dispensing dental materials. Conventionally, in the dental field, dental cement capsules have been widely used as containers for two-component mixed-kneading dental cements. When using dental cement capsules, the two components are mixed and kneaded using an automatic mixer such as a capsule mixer, and then the capsule is attached to a filling tool such as an applier, and the kneaded material inside the capsule is applied to the treatment site, such as a cavity.

[0028] The dental resin-reinforced glass ionomer cement composition of the present invention contains, as essential components, (a) acid-reactive glass powder, (b) polyalkenoic acid, (c) water, (d) polymerizable monomer, a specific (e) porous inorganic filler, and (f) a polymerization initiator, and the (e) porous inorganic filler is blended in a specific amount. This component configuration results in less stringiness of the mixed product, excellent cavity filling properties and application properties to dental prosthetic devices, and allows for shaping operations to be performed quickly after mixing, while also exhibiting good mixability, mechanical properties, and transparency.

[0029] Furthermore, the dental resin-reinforced glass ionomer cement composition of the present invention further contains (g) an organic-inorganic composite filler, and by setting the total content and content ratio of (e) porous inorganic filler and (g) organic-inorganic composite filler within a specific range, the viscosity of the kneaded product can be kept low and kneading properties can be further improved. The above-mentioned components of the present invention will be described in detail below.

[0030] <(a) Acid-reactive glass powder> The (a) acid-reactive glass powder that can be used in the dental resin-reinforced glass ionomer cement composition of the present invention is a component that contributes to the hardening of the composition and must contain an acid-reactive element, such as a metal element, and fluorine. The (a) acid-reactive glass powder contains an acid-reactive element, which, in the presence of (c) water, undergoes an acid-base reaction with the acidic group of (b) the polyalkenoic acid. Specific examples of acid-reactive elements include, but are not limited to, sodium, potassium, calcium, strontium, barium, lanthanum, aluminum, and zinc. One or more of these acid-reactive elements may be present, and the amount of each element is not particularly limited.

[0031] Furthermore, in order to impart radiopacity to the dental resin-reinforced glass ionomer cement composition of the present invention, it is preferable that the (a) acid-reactive glass powder contains a radiopaque element. Specific examples of radiopaque elements include, but are not limited to, strontium, lanthanum, zirconium, titanium, yttrium, ytterbium, tantalum, tin, tellurium, tungsten, and bismuth. Furthermore, there are no particular limitations on the other elements contained in the (a) acid-reactive glass powder, and the (a) acid-reactive glass powder of the present invention can contain a variety of elements.

[0032] (a) Examples of acid-reactive glass powders include, but are not limited to, aluminosilicate glass, borosilicate glass, aluminoborate glass, boroaluminosilicate glass, phosphate glass, borate glass, and silicate glass containing the above-mentioned acid-reactive elements, fluorine, and radiopaque elements.

[0033] Furthermore, the particle shape of the (a) acid-reactive glass powder is not particularly limited, and any particle shape such as spherical, needle-like, plate-like, crushed, scale-like, etc. can be used without any limitation. These (a) acid-reactive glass powders can be used alone or in combination.

[0034] The method for producing these (a) acid-reactive glass powders is not particularly limited, and any of the methods such as a melting method, a vapor phase method, and a sol-gel method can be used without any problems. Among these, it is preferable to use the (a) acid-reactive glass powder produced by the melting method or the sol-gel method, which allows for easy control of the type and content of elements.

[0035] (a) The acid-reactive glass powder can be used after being pulverized to a desired particle size. The pulverization method is not particularly limited, and either wet or dry pulverization can be used. Specifically, the raw glass can be pulverized using a high-speed rotary mill such as a hammer mill or turbo mill, a container-driven mill such as a ball mill, planetary mill, or vibration mill, a media-agitating mill such as an attritor or bead mill, or a jet mill, and the particle size can be appropriately adjusted depending on the desired properties to be imparted to the dental resin-reinforced glass ionomer cement composition of the present invention.

[0036] The 50% particle size (D50) of the (a) acid-reactive glass powder is preferably 0.5 μm or more and 20 μm or less, and more preferably 2.0 μm or more and 15 μm or less. The dental resin-reinforced glass ionomer cement composition of the present invention may contain only acid-reactive glass powder having a 50% particle size (D50) of 0.5 μm or more and 20 μm or less as the (a) acid-reactive glass powder.

[0037] (a) If the 50% particle size (D50) of the acid-reactive glass powder is less than 0.5 μm, its surface area increases, making it impossible to incorporate a large amount into the composition, which may result in reduced mechanical properties. Furthermore, the working time may be significantly shortened. (a) If the 50% particle size (D50) of the acid-reactive glass powder is greater than 20 μm, the mechanical properties may be reduced. Furthermore, when used as a filling material, the material surface may become rough after polishing, which may lead to increased discoloration in the oral cavity. When used as a bonding material, the coating thickness may increase, causing the bonded and / or adhered dental prosthetic device to lift, resulting in the intended fit of the dental prosthetic device being lost.

[0038] In order to adjust the handling, hardening characteristics, mechanical properties, etc. of the dental resin-reinforced glass ionomer cement composition of the present invention, (a) the acid-reactive glass powder can be subjected to various surface treatments, heat treatments, or aggregation treatments in a liquid phase or a gas phase, etc., within a range that does not adversely affect the acid-base reaction with (b) the polyalkenoic acid. These treatments can be performed alone or in combination, and the order in which each treatment is performed is not particularly limited. Among these, surface treatments and heat treatments are preferred because they allow for easy control of various properties and are also highly productive.

[0039] Specific examples of surface treatments of the (a) acid-reactive glass powder include washing with an acid such as phosphoric acid or acetic acid, surface treatment with an acidic compound such as tartaric acid or a polycarboxylic acid, surface treatment with a fluoride such as aluminum fluoride, and surface treatment with a silane compound such as (meth)acryloyloxymethyltrimethoxysilane, 3-(meth)acryloyloxypropyltrimethoxysilane, 8-(meth)acryloyloxyoctyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, tetramethoxysilane, tetraethoxysilane, a partially hydrolyzed oligomer of tetramethoxysilane, and a partially hydrolyzed oligomer of tetraethoxysilane. Surface treatments are not limited to those described above, and these surface treatments can be used alone or in combination. Furthermore, the amount of surface treatment agent relative to the (a) acid-reactive glass powder when performing the surface treatment is not particularly limited, and can be adjusted appropriately depending on the particle size and desired properties of the (a) acid-reactive glass powder.

[0040] (a) A specific example of the heat treatment of the acid-reactive glass powder is a treatment method in which the powder is heated at 200°C to 800°C for 1 hour to 72 hours using an electric furnace or the like. The heat treatments that can be used in the present invention are not limited to those described above, and the treatment process can also be a treatment at a single temperature or a multi-stage treatment at multiple temperatures.

[0041] The (a) acid-reactive glass powder is preferably contained in an amount of 30% by mass or more and 80% by mass or less, and more preferably 45% by mass or more and 80% by mass or less, based on the total amount of the dental resin-reinforced glass ionomer cement composition of the present invention. If the content of the (a) acid-reactive glass powder is less than 30% by mass, the mechanical properties may be reduced. On the other hand, if the content of the (a) acid-reactive glass powder is more than 80% by mass, the working time may be significantly shortened, or the viscosity of the mixed product may increase, resulting in poor mixing properties, which may adversely affect the workability.

[0042] <(b) Polyalkenoic acid> The (b) polyalkenoic acid that can be used in the dental resin-reinforced glass ionomer cement composition of the present invention is a component that contributes to the hardening of the composition. The (b) polyalkenoic acid can be any homopolymer or copolymer of an ethylenically unsaturated monomer having at least one carboxy group in the molecule, such as an ethylenically unsaturated monocarboxylic acid, an ethylenically unsaturated dicarboxylic acid, or an ethylenically unsaturated tricarboxylic acid. Furthermore, the (b) polyalkenoic acid may be a copolymer of an ethylenically unsaturated monomer having a carboxy group with an ethylenically unsaturated monomer that does not have a carboxy group in the molecule and / or an ethylenically unsaturated monomer having an acidic group other than a carboxy group, such as a phosphate group, phosphonate group, or sulfonate group. However, even in such copolymers, the carboxy-containing ethylenically unsaturated monomer units preferably account for 60% or more, more preferably 70% or more, and most preferably 80% or more.

[0043] Specific examples of ethylenically unsaturated monomers having a carboxy group that can be used to obtain (b) polyalkenoic acids include, but are not limited to, ethylenically unsaturated monocarboxylic acids such as acrylic acid, methacrylic acid, 2-chloroacrylic acid, 3-chloroacrylic acid, and 2-cyanoacrylic acid, ethylenically unsaturated dicarboxylic acids such as mesaconic acid, maleic acid, maleic anhydride, itaconic acid, itaconic anhydride, fumaric acid, glutaconic acid, and citraconic acid, and ethylenically unsaturated tricarboxylic acids such as aconitic acid, 1-butene-1,2,4-tricarboxylic acid, and 3-butene-1,2,3-tricarboxylic acid. Among these, it is preferable to use (b) polyalkenoic acids synthesized using only acrylic acid as a starting material, or (b) polyalkenoic acids synthesized using two or more starting materials, such as acrylic acid and maleic acid, acrylic acid and maleic anhydride, acrylic acid and itaconic acid, or acrylic acid and 3-butene-1,2,3-tricarboxylic acid.

[0044] The polymerization method used to obtain various (b) polyalkenoic acids is not particularly limited, and any polymerization method such as solution polymerization, suspension polymerization, or emulsion polymerization can be used without any restrictions. Furthermore, known polymerization initiators and chain transfer agents can be used during polymerization, and the amounts added can be adjusted appropriately depending on the desired properties. The (b) polyalkenoic acids obtained in this manner can be used alone or in combination.

[0045] The weight-average molecular weight of the (b) polyalkenoic acid is preferably 30,000 or more and 300,000 or less. Here, the weight-average molecular weight is the average molecular weight calculated based on the molecular weight distribution measured by gel permeation chromatography. If the weight-average molecular weight of the (b) polyalkenoic acid is less than 30,000, the mechanical properties may be reduced. On the other hand, if the weight-average molecular weight of the (b) polyalkenoic acid is more than 300,000, the working time may be significantly shortened, or the viscosity of the mixed product may increase, resulting in poor mixing properties, which may adversely affect workability. The dental resin-reinforced glass ionomer cement composition of the present invention may also contain only polyalkenoic acids with a weight-average molecular weight of 30,000 or more and 300,000 or less as the (b) polyalkenoic acid.

[0046] Furthermore, (b) polyalkenoic acid can be used after neutralizing some of its carboxyl groups with a basic compound to adjust the acid-base reactivity with (a) acid-reactive glass powder, as long as the neutralization does not adversely affect various properties. Examples of basic compounds used for neutralization include alkali metal hydroxides such as sodium hydroxide, potassium hydroxide, and lithium hydroxide; alkali metal carbonates such as sodium carbonate, potassium carbonate, and lithium carbonate; and alkali metal bicarbonates such as sodium bicarbonate, potassium bicarbonate, and lithium bicarbonate. Various amine compounds, such as primary amines, secondary amines, and tertiary amines, can also be used without any problems. Suitable amine compounds include triethanolamine, diethanolamine, N-methyldiethanolamine, and 2-dimethylaminoethyl (meth)acrylate.

[0047] The (b) polyalkenoic acid is preferably contained in an amount of 0.5% by mass to 17% by mass, more preferably 3% by mass to 11% by mass, based on the total amount of the dental resin-reinforced glass ionomer cement composition of the present invention. If the (b) polyalkenoic acid content is less than 0.5% by mass, the mechanical properties may be reduced. If the (b) polyalkenoic acid content exceeds 17% by mass, the working time may be significantly shortened, or the viscosity of the mixed product may increase, resulting in poor mixing properties, which may adversely affect the workability.

[0048] <(c)Water> (c) Water, which can be used in the dental resin-reinforced glass ionomer cement composition of the present invention, functions as a solvent for dissolving (b) polyalkenoic acid, and also serves as a component for diffusing metal ions eluted from (a) the acid-reactive glass powder and inducing a crosslinking reaction between (b) polyalkenoic acids.

[0049] (c) Water can be used without any restrictions as long as it does not contain impurities that inhibit the acid-base reaction in the dental resin-reinforced glass ionomer cement composition of the present invention or that adversely affect the hardening properties or mechanical properties. However, it is preferable to use distilled water or ion-exchanged water.

[0050] The content of (c) water is preferably 0.5% by mass or more and 27% by mass or less, and more preferably 2% by mass or more and 14% by mass or less, of the total dental resin-reinforced glass ionomer cement composition of the present invention. If the content of (c) water is less than 0.5% by mass, it may have adverse effects on operability, such as a significant shortening of working time or an increase in the viscosity of the kneaded product, resulting in poor kneading. Furthermore, if the content of (c) water exceeds 27% by mass, it may result in a decrease in mechanical properties and transparency.

[0051] <(d) Polymerizable Monomer> The (d) polymerizable monomer that can be used in the dental resin-reinforced glass ionomer cement composition of the present invention is a component that contributes to the hardening of the composition. The (d) polymerizable monomer is not particularly limited in terms of its molecular structure, and any known polymerizable monomer can be used. Specifically, examples of the polymerizable unsaturated group possessed by the (d) polymerizable monomer include, but are not limited to, a (meth)acryloyloxy group, a (meth)acrylamide group, a styryl group, a vinyl group, and an allyl group. Among these polymerizable unsaturated groups, a (meth)acryloyloxy group or a (meth)acrylamide group is preferred due to its excellent polymerization rate. Furthermore, the number of polymerizable unsaturated groups possessed by the (d) polymerizable monomer is not particularly limited. The hydrocarbon group bonded to the polymerizable unsaturated group may be an aliphatic hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, or a combination thereof. Furthermore, the hydrocarbon group may have any substituent, such as an acidic group, a hydroxyl group, a halogen atom, an alkoxy group, an amino group, or a glycidyl group. Specific examples of (d) polymerizable monomers are given below.

[0052] Examples of the monofunctional polymerizable monomer include (meth)acrylic acid, methyl (meth)acrylate, ethyl (meth)acrylate, isopropyl (meth)acrylate, n-propyl (meth)acrylate, isobutyl (meth)acrylate, n-butyl (meth)acrylate, t-butyl (meth)acrylate, sec-butyl (meth)acrylate, n-amyl (meth)acrylate, isoamyl (meth)acrylate, n-hexyl (meth)acrylate, isodecyl (meth)acrylate, lauryl (meth)acrylate, and stearyl (meth)acrylate. Acrylate, 2-ethylhexyl (meth)acrylate, cyclohexyl (meth)acrylate, adamantyl (meth)acrylate, phenyl (meth)acrylate, phenoxydiethylene glycol (meth)acrylate, methoxypolyethylene glycol (meth)acrylate, benzyl (meth)acrylate, 2-phenylethyl (meth)acrylate, o-phenoxybenzyl (meth)acrylate, m-phenoxybenzyl (meth)acrylate, p-phenoxybenzyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate ) acrylate, glycidyl (meth)acrylate, isobornyl (meth)acrylate, allyl (meth)acrylate, 2-methoxyethyl (meth)acrylate, 2-ethoxyethyl (meth)acrylate, phenoxyethyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, glycerol (meth)acrylate, (meth)acryloyloxyethyl methyl succinate, 2 (Meth)acrylic acid esters such as (meth)acryloyloxyethyl propionate, acetoacetoxyethyl (meth)acrylate, acetoacetoxypropyl (meth)acrylate, and acetoacetoxybutyl (meth)acrylate; silane compounds such as 3-(meth)acryloyloxypropyltrimethoxysilane and 3-(meth)acryloyloxypropyltriethoxysilane; amines such as 2-(N,N-dimethylamino)ethyl (meth)acrylate and 2-(N,N-diethylamino)ethyl (meth)acrylate; 2,2,Examples include fluorine-containing (meth)acrylates such as 2-trifluoroethyl (meth)acrylate, perfluorohexylethyl (meth)acrylate, and perfluorooctylethyl (meth)acrylate, as well as their (meth)acrylamides and N-methylol (meth)acrylamide.

[0053] Examples of aromatic bifunctional polymerizable monomers include 2,2-bis[4-[3-(meth)acryloyloxy-2-hydroxypropoxy]phenyl]propane, 2,2-bis(4-(meth)acryloyloxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxyethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxydiethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxytetraethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxypentaethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxydipropoxyphenyl)propane, 2-(4-(meth)acryloyloxyethoxyphenyl)- ...

[0033] Examples of the acryloyloxydiethoxyphenyl propane include 2-(4-(meth)acryloyloxydiethoxyphenyl)-2-(4-(meth)acryloyloxytriethoxyphenyl)propane, 2-(4-(meth)acryloyloxydipropoxyphenyl)-2-(4-(meth)acryloyloxytriethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxydipropoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxyisopropoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxypolyethoxyphenyl)propane, 9,9-bis[4-(2-(meth)acryloyloxyethoxy)phenyl]fluorene, and (meth)acrylamides thereof.

[0054] Examples of the aliphatic bifunctional polymerizable monomer include ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 3-methyl-1,5-pentanediol di(meth)acrylate, 1,3-butanediol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,9- Examples of the acrylate include nonanediol di(meth)acrylate, 1,10-decanediol di(meth)acrylate, tricyclodecane dimethanol di(meth)acrylate, glycerol-1,3-dimethacrylate, 3-hydroxypropyl-1,2-di(meth)acrylate, 2-hydroxy-3-acryloyloxypropyl (meth)acrylate, 1,2-bis(3-(meth)acryloyloxy-2-hydroxypropoxy)ethane, 1,2-bis(3-(meth)acryloyloxy-2-hydroxypropoxy)propane, 2-hydroxy-1,3-bis(3-(meth)acryloyloxy-2-hydroxypropoxy)propane, and (meth)acrylamides thereof.

[0055] Examples of the tri- or higher functional polymerizable monomer include trimethylolpropane tri(meth)acrylate, trimethylolethane tri(meth)acrylate, trimethylolmethane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, glycerin tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, and (meth)acrylamides thereof.

[0056] Examples of urethane-based polymerizable monomers include (meth)acrylate compounds having a urethane bond derived from an adduct of a polymerizable monomer having a hydroxyl group, such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, or 3-chloro-2-hydroxypropyl (meth)acrylate, with an isocyanate compound, such as methylcyclohexane diisocyanate, methylenebis(4-cyclohexyl isocyanate), hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, isophorone diisocyanate, diisocyanate methylmethylbenzene, or 4,4-diphenylmethane diisocyanate.

[0057] Furthermore, since the (d) polymerizable monomer has excellent compatibility with other hydrophilic components, it is more preferable to use a hydroxyl group-containing polymerizable monomer having at least one hydroxyl group and at least one (meth)acryloyloxy group or (meth)acrylamide group as a polymerizable unsaturated group in the molecule. Specific examples of hydroxyl group-containing polymerizable monomers are shown below.

[0058] Examples of hydroxyl group-containing polymerizable monomers include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 5-hydroxypentyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, 10-hydroxydecyl (meth)acrylate, diethylene glycol mono(meth)acrylate, triethylene glycol mono(meth)acrylate, tetraethylene glycol mono(meth)acrylate, polyethylene glycol mono(meth)acrylate, dipropylene glycol mono(meth)acrylate, polypropylene glycol mono(meth)acrylate, 2,3-dihydro Examples of the polymerizable monomer include monofunctional polymerizable monomers such as 2-hydroxypropyl (meth)acrylate, glycerin mono(meth)acrylate, erythritol mono(meth)acrylate, addition products of phenols and glycidyl (meth)acrylate, for example, 2-hydroxy-3-phenoxypropyl (meth)acrylate, 2-hydroxy-3-naphthoxypropyl (meth)acrylate, and (meth)acrylamides thereof; and polyfunctional polymerizable monomers such as glycerol-1,3-dimethacrylate, 3-hydroxypropyl-1,2-di(meth)acrylate, bisphenol A diglycidyl (meth)acrylate, and 2-hydroxy-3-acryloyloxypropyl (meth)acrylate, and (meth)acrylamides thereof. Further examples include polyfunctional polymerizable monomers in which two or more hydroxyl groups of sugar alcohols (erythritol, arabinitol, xylitol, ribitol, iditol, galactitol, sorbitol, mannitol, etc.), monosaccharides (arabinose, xylose, mannose, galactose, fructose, etc.), disaccharides (sucrose, maltose, lactose, trehalose, etc.), and trisaccharides (maltotriose, raffinose, etc.) have been substituted with (meth)acryloyloxy groups or (meth)acrylamide groups.

[0059] Furthermore, as the (d) polymerizable monomer, an acidic group-containing polymerizable monomer containing at least one acidic group in the molecule can be used as desired to improve adhesion to teeth, base metals, alumina, zirconia, etc. Examples of the acidic group contained in the acidic group-containing polymerizable monomer include a phosphate group, a pyrophosphate group, a phosphonate group, a carboxy group, a sulfonic acid group, and a thiophosphate group. Specific examples of acidic group-containing polymerizable monomers are listed below.

[0060] Examples of the phosphoric acid group-containing polymerizable monomer include (meth)acryloyloxymethyl dihydrogen phosphate, 2-(meth)acryloyloxyethyl dihydrogen phosphate, 3-(meth)acryloyloxypropyl dihydrogen phosphate, 4-(meth)acryloyloxybutyl dihydrogen phosphate, 5-(meth)acryloyloxypentyl dihydrogen phosphate, 6-(meth)acryloyloxyhexyl dihydrogen phosphate, 7-(meth)acryloyloxyheptyl dihydrogen phosphate, Acryloyloxybenzoate, 8-(meth)acryloyloxyoctyl dihydrogen phosphate, 9-(meth)acryloyloxynonyl dihydrogen phosphate, 10-(meth)acryloyloxydecyl dihydrogen phosphate, 11-(meth)acryloyloxyundecyl dihydrogen phosphate, 12-(meth)acryloyloxydodecyl dihydrogen phosphate, 16-(meth)acryloyloxyhexadecyl dihydrogen phosphate, 20-(meth)acryloyloxyeicosyl dihydrogen phosphate hydrogen phosphate, bis[2-(meth)acryloyloxyethyl]hydrogen phosphate, bis[3-(meth)acryloyloxypropyl]hydrogen phosphate, bis[4-(meth)acryloyloxybutyl]hydrogen phosphate, bis[6-(meth)acryloyloxyhexyl]hydrogen phosphate, bis[8-(meth)acryloyloxyoctyl]hydrogen phosphate, bis[9-(meth)acryloyloxynonyl]hydrogen phosphate, bis[10-(meth)acryloyloxyethyl]hydrogen phosphate, Examples of suitable alkyl acrylates include 2-(meth)acryloyloxydecyl)hydrogen phosphate, 1,3-di(meth)acryloyloxypropyl-2-dihydrogen phosphate, 2-(meth)acryloyloxyethylphenyl hydrogen phosphate, 2-(meth)acryloyloxyethyl-2'-bromoethyl hydrogen phosphate, 2-(meth)acryloyloxyethyl-(4-methoxyphenyl)hydrogen phosphate, and 2-(meth)acryloyloxypropyl-(4-methoxyphenyl)hydrogen phosphate.

[0061] Examples of the pyrophosphate group-containing polymerizable monomer include bis[2-(meth)acryloyloxyethyl] pyrophosphate, bis[3-(meth)acryloyloxypropyl] pyrophosphate, bis[4-(meth)acryloyloxybutyl] pyrophosphate, bis[5-(meth)acryloyloxypentyl] pyrophosphate, bis[6-(meth)acryloyloxyhexyl] pyrophosphate, bis[7-(meth)acryloyloxyheptyl] pyrophosphate, bis[8-(meth)acryloyloxyoctyl] pyrophosphate, bis[9-(meth)acryloyloxynonyl] pyrophosphate, bis[10-(meth)acryloyloxydecyl] pyrophosphate, bis[12-(meth)acryloyloxydodecyl] pyrophosphate, tris[2-(meth)acryloyloxyethyl] pyrophosphate, and tetra[2-(meth)acryloyloxyethyl] pyrophosphate.

[0062] Examples of the phosphonic acid group-containing polymerizable monomer include 5-(meth)acryloyloxypentyl-3-phosphonopropionate, 6-(meth)acryloyloxyhexyl-3-phosphonopropionate, 10-(meth)acryloyloxydecyl-3-phosphonopropionate, 6-(meth)acryloyloxyhexyl-3-phosphonoacetate, 10-(meth)acryloyloxydecyl-3-phosphonoacetate, and (meth)acryloyloxyethyl phenylphosphonate.

[0063] Examples of carboxy group-containing polymerizable monomers include (meth)acrylic acid, 2-chloroacrylic acid, 3-chloro(meth)acrylic acid, 2-cyanoacrylic acid, 1,4-di(meth)acryloyloxyethylpyromellitic acid, 6-(meth)acryloyloxynaphthalene-1,2,6-tricarboxylic acid, 1-butene-1,2,4-tricarboxylic acid, 3-butene-1,2,3-tricarboxylic acid, N-(meth)acryloyl-p-aminobenzoic acid, N-(meth)acryloyl-5-aminosalicylic acid, 4-(meth)acryloyloxyethyltrimellitic acid and its anhydride, 4-(meth)acryloyloxybutyltrimellitic acid and its anhydride, 2-(meth)acryloyloxybenzoic acid, β-(meth)acryloyloxyethyl hydrogen succinate, β-(meth)acryloyloxyethyl hydrogen maleate, Examples of suitable phthalates include 11-(meth)acryloyloxy-1,1-undecanedicarboxylic acid, p-vinylbenzoic acid, 4-(meth)acryloyloxyethoxycarbonylphthalic acid, 4-(meth)acryloyloxybutyloxycarbonylphthalic acid, 4-(meth)acryloyloxyhexyloxycarbonylphthalic acid, 4-(meth)acryloyloxyoctyloxycarbonylphthalic acid, 4-(meth)acryloyloxydecyloxycarbonylphthalic acid, and acid anhydrides thereof, 5-(meth)acryloylaminopentylcarboxylic acid, 6-(meth)acryloyloxy-1,1-hexanedicarboxylic acid, 8-(meth)acryloyloxy-1,1-octanedicarboxylic acid, 10-(meth)acryloyloxy-1,1-decanedicarboxylic acid, and 11-(meth)acryloyloxy-1,1-undecanedicarboxylic acid.

[0064] Examples of sulfonic acid group-containing polymerizable monomers include 2-(meth)acrylamido-2-methylpropanesulfonic acid, styrenesulfonic acid, 2-sulfoethyl (meth)acrylate, 4-(meth)acryloyloxybenzenesulfonic acid, and 3-(meth)acryloyloxypropanesulfonic acid.

[0065] Examples of the thiophosphate group-containing polymerizable monomer include 2-(meth)acryloyloxyethyl dihydrogen thiophosphate, 3-(meth)acryloyloxypropyl dihydrogen thiophosphate, 4-(meth)acryloyloxybutyl dihydrogen thiophosphate, 5-(meth)acryloyloxypentyl dihydrogen thiophosphate, 6-(meth)acryloyloxyhexyl dihydrogen thiophosphate, 7-(meth)acryloyloxyheptyl dihydrogen thiophosphate, 8-(meth)acryloyloxyethyl dihydrogen thiophosphate, 9-(meth)acryloyloxyethyl dihydrogen thiophosphate, 10-(meth)acryloyloxyethyl dihydrogen thiophosphate, 11-(meth)acryloyloxyethyl dihydrogen thiophosphate, 12-(meth)acryloyloxyethyl dihydrogen thiophosphate, 13-(meth)acryloyloxyethyl dihydrogen thiophosphate, 14-(meth)acryloyloxyethyl dihydrogen thiophosphate, 15-(meth)acryloyloxyethyl dihydrogen thiophosphate, 16-(meth)acryloyloxyethyl dihydrogen thiophosphate, 17-(meth)acryloyloxyethyl dihydrogen thiophosphate, 18-(meth)acryloyloxyethyl dihydrogen thiophosphate, 19-(meth)acryloyloxyethyl dihydrogen thiophosphate, 20-(meth)acryloyloxyethyl dihydrogen thiophosphate, 21-(meth)acryloyloxyethyl dihydrogen thiophosphate, 22-(meth)acryloyloxyethyl dihydrogen thiophosphate, 23-(meth)acryloyloxyethyl dihydrogen thiophosphate, 24-(meth)acryloyloxyethyl dihydrogen thiophosphate, 25-(meth)acryloyloxyethyl dihydrogen thiophosphate, 26-(meth)acryloyloxyethyl dihydrogen thiophosphate, 2 Examples of the acryloyloxypropyl methyl acrylate include octyl dihydrogen thiophosphate, 9-(meth)acryloyloxynonyl dihydrogen thiophosphate, 10-(meth)acryloyloxydecyl dihydrogen thiophosphate, 11-(meth)acryloyloxyundecyl dihydrogen thiophosphate, 12-(meth)acryloyloxydodecyl dihydrogen thiophosphate, 16-(meth)acryloyloxyhexadecyl dihydrogen thiophosphate, and 20-(meth)acryloyloxyeicosyl dihydrogen thiophosphate.

[0066] Among these acidic group-containing polymerizable monomers, it is preferable to use a carboxyl group-containing polymerizable monomer because of its excellent effect of improving adhesiveness, and it is more preferable to use a polymerizable monomer having two or more carboxyl groups. Note that the dental resin-reinforced glass ionomer cement composition of the present invention may not contain an acidic group-containing polymerizable monomer as the (d) polymerizable monomer.

[0067] Furthermore, as the (d) polymerizable monomer, a polymerizable monomer having a sulfur atom in the molecule, a polymerizable monomer having a fluoro group, an oligomer having at least one polymerizable group, or a polymer may be used. The (d) polymerizable monomers shown above are not limited to these, and may be used alone or in combination.

[0068] The (d) polymerizable monomer is preferably contained in an amount of 2% by mass to 48% by mass, and more preferably 4% by mass to 36% by mass, based on the total mass of the dental resin-reinforced glass ionomer cement composition of the present invention. If the (d) polymerizable monomer content is less than 2% by mass, the chemical polymerization reaction and / or photopolymerization reaction may not occur sufficiently, resulting in reduced mechanical properties. Furthermore, if the (d) polymerizable monomer content exceeds 48% by mass, the compatibility of (b) polyalkenoic acid, (c) water, and (d) polymerizable monomer may be reduced, resulting in a non-uniform cured product and reduced mechanical properties and transparency.

[0069] <(e) Porous inorganic filler> The (e) porous inorganic filler that can be used in the dental resin-reinforced glass ionomer cement composition of the present invention is an inorganic filler having at least one pore, and is a component for reducing stringiness of the kneaded product in the composition. The presence or absence of pores in the inorganic filler can be measured, for example, by gas adsorption or mercury intrusion porosimetry. More specifically, in this specification, the (e) porous inorganic filler refers to one having a pore volume of 0.01 cc / g or more as measured by gas adsorption. Note that the dental resin-reinforced glass ionomer cement composition of the present invention may not contain any fillers other than the (e) porous inorganic filler.

[0070] The shape of the (e) porous inorganic filler is not particularly limited, but is preferably spherical or crushed, since this has relatively little effect on the viscosity of the kneaded product in the dental resin-reinforced glass ionomer cement composition of the present invention. The 50% particle size (D50) of the (e) porous inorganic filler is preferably 0.1 μm or more and 10 μm or less, and more preferably 1 μm or more and 8 μm or less. If the 50% particle size (D50) of the (e) porous inorganic filler exceeds 10 μm, the mechanical properties of the dental resin-reinforced glass ionomer cement composition of the present invention may be reduced. If the 50% particle size (D50) is less than 0.1 μm, this may adversely affect the kneading properties and kneaded product properties.

[0071] The pore volume of the (e) porous inorganic filler is preferably 0.01 cc / g or more and 1.00 cc / g or less, and more preferably 0.08 cc / g or more and 0.80 cc / g or less. The specific surface area of ​​the (e) porous inorganic filler is preferably 5 m 2 / g or more 500m 2 / g or less, and 2 / g or more 300m 2 / g or less. (e) Porous inorganic filler having such properties can effectively reduce stringiness of the kneaded product in the dental resin-reinforced glass ionomer cement composition of the present invention. If the pore volume and / or specific surface area of ​​the (e) porous inorganic filler is less than the above range, the effect of reducing stringiness of the kneaded product may be difficult to achieve. If the pore volume and / or specific surface area exceeds the above range, the mechanical properties may be reduced. Note that the dental resin-reinforced glass ionomer cement composition of the present invention contains (e) porous inorganic filler having a 50% particle size (D50) of 0.1 μm or more and 10 μm or less, a pore volume of 0.01 cc / g or more and 1.00 cc / g or less, and a specific surface area of ​​5 m 2 / g or more 500m 2 It is also possible to include only a porous inorganic filler of 0.1g or less.

[0072] (e) The porous inorganic filler has a core composed of inorganic particles composed solely of silicon dioxide or of silicon dioxide and an oxide containing one or more metal elements. Examples of oxides containing metal elements include, but are not limited to, oxides of metal elements such as Al, Ba, Bi, Ca, Ce, Co, Cu, Er, Fe, Hf, Ho, In, La, Mg, Mn, Nd, Ni, Pb, Sb, Sn, Sr, Ta, Ti, Y, Yb, Zn, and Zr. Among these, oxides of Al, Ba, Ca, Co, Cu, Fe, Hf, La, Mg, Ni, Sr, Ti, Zn, and Zr are preferred, oxides of Ba, Ti, Zr, etc. are more preferred, and oxide of Zr is even more preferred. The dental resin-reinforced glass ionomer cement composition of the present invention may contain only oxides of Al, Ba, Ca, Co, Cu, Fe, Hf, La, Mg, Ni, Sr, Ti, Zn, and Zr as oxides containing metal elements constituting the inorganic particles at the center of the (e) porous inorganic filler, or may contain only oxides of Ba, Ti, and Zr, or may contain only oxide of Zr.

[0073] The oxide content of the metal element contained in the inorganic particles at the center of the (e) porous inorganic filler is preferably 30% by mass or less in terms of oxide content. If the oxide content of the metal element exceeds 30% by mass, the refractive index of the (e) porous inorganic filler becomes too high, which may cause the dental resin-reinforced glass ionomer cement composition of the present invention to become opaque.

[0074] The inorganic particles at the center of the (e) porous inorganic filler can be produced, for example, by mixing an acidic silicic acid liquid, a silicon dioxide sol, and optionally one or more aqueous metal salt solutions, spray-drying the mixed slurry, and then heat-treating the resulting dried particles.Details of the production method for the (e) porous inorganic filler are disclosed in, for example, JP 2019-189637 A, but are not limited to these production methods.

[0075] Furthermore, in order to adjust the fluidity of the powder material and the properties of the paste in the dental resin-reinforced glass ionomer cement composition of the present invention, the (e) porous inorganic filler can optionally be surface-treated with a silane compound such as (meth)acryloyloxymethyltrimethoxysilane, 3-(meth)acryloyloxypropyltrimethoxysilane, 8-(meth)acryloyloxyoctyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, or 3-glycidoxypropyltrimethoxysilane. Surface treatment agents are not limited to those listed above, and these surface treatment agents can be used alone or in combination. Furthermore, the amount of surface treatment agent relative to the inorganic particles at the center of the (e) porous inorganic filler is not particularly limited, and can be adjusted as needed depending on the particle size, pore volume, specific surface area, and desired properties of the inorganic particles at the center of the (e) porous inorganic filler.

[0076] The (e) porous inorganic filler must be contained in an amount of 1% by mass to 15% by mass, and more preferably 3% by mass to 10% by mass, based on the total amount of the dental resin-reinforced glass ionomer cement composition of the present invention. If the (e) porous inorganic filler content is less than 1% by mass, the effect of reducing stringiness of the kneaded product will not be achieved. On the other hand, if the (e) porous inorganic filler content exceeds 15% by mass, the mechanical properties will be reduced and the viscosity of the kneaded product will increase, resulting in poor kneadability.

[0077] <(f) Polymerization initiator> The (f) polymerization initiator that can be used in the dental resin-reinforced glass ionomer cement composition of the present invention is not particularly limited, and any known polymerization initiator used in the dental field can be used without any restriction. (f) Polymerization initiators include those that initiate radical polymerization through the action of a compound consisting of two or more components, such as redox initiators (sometimes referred to as "chemical polymerization initiators" in the dental field; hereinafter referred to as "chemical polymerization initiators"), and those that initiate radical polymerization through light irradiation (photopolymerization initiators). In the present invention, any polymerization initiator can be used without any restriction. As long as the (f) polymerization initiator can sufficiently polymerize the (d) polymerizable monomer, there is no particular restriction on how it can be incorporated into the dental resin-reinforced glass ionomer cement composition of the present invention. For example, when the dental resin-reinforced glass ionomer cement composition of the present invention is composed of a powder material and a liquid material, or a first paste and a second paste, the (f) polymerization initiator may be incorporated into both of them, or into either the powder material and the liquid material, or the first paste and the second paste. The dental resin-reinforced glass ionomer cement composition of the present invention may contain only a chemical polymerization initiator as the (f) polymerization initiator. The dental resin-reinforced glass ionomer cement composition of the present invention may not contain a chemical polymerization initiator as the (f) polymerization initiator. The dental resin-reinforced glass ionomer cement composition of the present invention may contain only a photopolymerization initiator as the (f) polymerization initiator. The dental resin-reinforced glass ionomer cement composition of the present invention may not contain a photopolymerization initiator as the (f) polymerization initiator. The dental resin-reinforced glass ionomer cement composition of the present invention may contain only a chemical polymerization initiator and a photopolymerization initiator as the (f) polymerization initiator. The dental resin-reinforced glass ionomer cement composition of the present invention may contain both a chemical polymerization initiator and a photopolymerization initiator as the (f) polymerization initiator.

[0078] Examples of chemical polymerization initiators include, but are not limited to, peroxide / amine compound, peroxide / amine compound / aromatic sulfinic acid or its salt, or aromatic sulfonyl compound, peroxide / amine compound / (thio)barbituric acid compound or (thio)barbiturate compound, peroxide / amine compound / borate compound, peroxide / ascorbic acid compound, peroxide / thiourea / vanadium compound or copper compound, (thio)barbituric acid compound / organometallic compound / organohalogen compound, aromatic sulfinic acid salts that initiate radical polymerization by the action of an acidic compound, borate compounds, or (thio)barbiturates, combined with an acidic compound, and further organic boron compounds that react with oxygen or water to initiate radical polymerization.

[0079] Examples of peroxides include sodium peroxodisulfate, potassium peroxodisulfate, ammonium peroxodisulfate, sodium peroxodiphosphate, potassium peroxodiphosphate, ammonium peroxodiphosphate, diacyl peroxides, alkyl peroxy esters, peroxydicarbonates, monoperoxycarbonates, peroxyketals, dialkyl peroxides, hydroperoxides, and ketone peroxides. More specific examples include benzoyl peroxide, p-chlorobenzoyl peroxide, 2,4-dichlorobenzoyl peroxide, diacetyl peroxide, lauroyl peroxide, di-t-butyl peroxide, dicumyl peroxide, cumene hydroperoxide, t-butyl hydroperoxide, 1,1,3,3-tetramethylbutyl hydroperoxide, t-amyl hydroperoxide, isopropylbenzene hydroperoxide, 5-phenyl-4-pentenyl hydroperoxide, t-butylperoxyisopropyl carbonate, methyl ethyl ketone peroxide, 1,1-bis(t-butylperoxy)cyclohexane, 1,1-bis(t-hexylperoxy)cyclohexane, and t-butyl peroxybenzoate, but are not limited to these.

[0080] The amine compound is preferably an aromatic secondary or aromatic tertiary amine, and specific examples thereof include N-methyl-p-toluidine, N-ethyl-p-toluidine, N-(2-hydroxyethyl)-p-toluidine, ethyl p-methylaminobenzoate, N-methylaniline, N-ethylaniline, N-(2-hydroxyethyl)aniline, N,N-dimethylaniline, N,N-diethylaniline, N,N-bis(2-hydroxyethyl)aniline, N-(2-hydroxyethyl)-N-methylaniline, N-ethyl-N-(2-hydroxyethyl)aniline, N,N-dimethyl-p-toluidine, N,N-diethyl-p-toluidine, N,N-bis(2-hydroxyethyl)-p-toluidine, ethyl p-dimethylaminobenzoate, and the like, but are not limited thereto.

[0081] Examples of aromatic sulfinic acids, salts thereof, or aromatic sulfonyl compounds include benzenesulfinic acid, p-toluenesulfinic acid, o-toluenesulfinic acid, 2,4,6-trimethylbenzenesulfinic acid, 2,4,6-triisopropylbenzenesulfinic acid, and sodium salts, potassium salts, lithium salts, or ammonium salts thereof; or benzenesulfonyl chloride, benzenesulfonyl fluoride, benzenesulfonamide, benzenesulfonyl hydrazide, p-toluenesulfonyl chloride, p-toluenesulfonyl fluoride, p-toluenesulfonamide, p-toluenesulfonyl hydrazide, etc., but are not limited to these.

[0082] Examples of (thio)barbituric acid compounds or (thio)barbiturate compounds 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, 5-laurylbarbituric acid, 1,3,5-trimethylbarbituric acid, 1,3-dimethyl-5-ethylbarbituric acid, 1,3-dimethyl-n-butylbarbituric acid, 1,3-dimethyl-5-isobutylbarbituric acid, 1,3-dimethyl-5-cyclohex ...isobutylbarbituric acid, 1,3-dimethyl-5-cyclohexylbarbituric acid, 1,3,5-trimethylbarbituric acid Examples of suitable barbituric acids include, but are not limited to, 1,3-dimethyl-5-phenylbarbituric acid, 1-cyclohexyl-5-ethylbarbituric acid, 1-phenyl-5-benzylbarbituric acid, 1-benzyl-5-phenylbarbituric acid, thiobarbituric acid, 1,3-dimethylthiobarbituric acid, 5-phenylthiobarbituric acid, and alkali metal salts (lithium, sodium, potassium salts, etc.), alkaline earth metal salts (calcium, strontium, barium salts, etc.), ammonium salts, tetramethylammonium salts, and tetraethylammonium salts thereof.

[0083] Examples of borate compounds include trialkylphenylboron, trialkyl(p-chlorophenyl)boron, trialkyl(p-fluorophenyl)boron, trialkyl(p-butylphenyl)boron, trialkyl(p-butyloxyphenyl)boron, monoalkyltriphenylboron, monoalkyltris(p-chlorophenyl)boron, monoalkyltris(p-fluorophenyl)boron, monoalkyltris(p-butylphenyl)boron, monoalkyltris(p-butyloxyphenyl)boron, tetraphenylboron, and tetrakis(phenyl)boron. Examples of the salt include, but are not limited to, sodium salts, potassium salts, lithium salts, magnesium salts, tetramethylammonium salts, tetraethylammonium salts, tetrabutylammonium salts, methylpyridinium salts, ethylpyridinium salts, methylquinolinium salts, and ethylquinolinium salts of (p-chlorophenyl)boron, tetrakis(p-fluorophenyl)boron, tetrakis(p-butylphenyl)boron, and tetrakis(p-butyloxyphenyl)boron (wherein the alkyl group is an n-butyl group, an n-octyl group, an n-dodecyl group, or the like).

[0084] Examples of ascorbic acid compounds include, but are not limited to, L(+)-ascorbic acid, isoascorbic acid, sodium L(+)-ascorbate, potassium L(+)-ascorbate, calcium L(+)-ascorbate, and sodium isoascorbate.

[0085] Examples of thiourea compounds include 1,3-dimethylthiourea, tetramethylthiourea, 1,1-diethylthiourea, 1,1,3,3-tetraethylthiourea, 1-allyl-2-thiourea, 1,3-diallylthiourea, 1,3-dibutylthiourea, 1,3-diphenyl-2-thiourea, 1,3-dicyclohexylthiourea, ethylenethiourea, N-methylthiourea, N-phenylthiourea, N-benzoylthiourea, and N-acetylthiourea, but are not limited to these.

[0086] Examples of vanadium compounds include, but are not limited to, vanadium acetylacetonate, vanadyl acetylacetonate, vanadyl stearate, vanadium naphthenate, and vanadium benzoylacetonate.

[0087] Examples of copper compounds include, but are not limited to, copper acetate, copper salicylate, copper gluconate, copper oleate, copper benzoate, copper acetylacetonate, and copper naphthenate.

[0088] Examples of the organometallic compound include, in addition to the copper compounds, manganese acetylacetone, manganese naphthenate, manganese octoate, cobalt acetylacetone, cobalt naphthenate, lithium acetylacetone, lithium acetate, zinc acetylacetone, zinc naphthenate, nickel acetylacetone, nickel acetate, aluminum acetylacetone, calcium acetylacetone, iron acetylacetone, chromium acetylacetone, and sodium naphthenate, but are not limited to these.

[0089] Examples of organic halogen compounds include, but are not limited to, tetramethylammonium chloride, tetraethylammonium chloride, trioctylmethylammonium chloride, dilauryldimethylammonium chloride, lauryldimethylbenzylammonium chloride, tetra-n-butylammonium chloride, benzyldimethylcetylammonium chloride, and benzyldimethylstearylammonium chloride.

[0090] As the acidic compound to be reacted with aromatic sulfinates, borate compounds, or (thio)barbiturates, either inorganic or organic acids can be used without any limitation, but organic acids are preferred. Furthermore, from the viewpoint of the stability of the cured product, it is most preferred to use an organic acid having a polymerizable group, i.e., an acidic group-containing polymerizable monomer. The acidic group-containing polymerizable monomer is not particularly limited in terms of the type or number of polymerizable groups or acidic groups, and those commonly used in the dental field can be used. Examples of acidic groups include carboxyl groups, phosphate groups, phosphonic acid groups, and sulfonic acid groups. Representative examples of acidic group-containing polymerizable monomers used in the dental field include, but are not limited to, 10-(meth)acryloyloxydecyl dihydrogen phosphate, 6-(meth)acryloyloxyhexyl-3-phosphonoacetate, 4-(meth)acryloyloxyethyl trimellitic acid and its anhydride, 10-(meth)acryloyloxy-1,1-decanedicarboxylic acid, etc. These acidic compounds can be used alone or in combination.

[0091] Examples of organic boron compounds that react with oxygen or water to initiate polymerization include, but are not limited to, trialkylborons such as triethylboron, tri(n-propyl)boron, triisopropylboron, tri(n-butyl)boron, tri(s-butyl)boron, triisobutylboron, tripentylboron, trihexylboron, and tricyclohexylboron, as well as partial oxides thereof.

[0092] Examples of the photopolymerization initiator include those composed of a photosensitizer, photosensitizer / photopolymerization accelerator, etc. Specific examples of the photosensitizer include α-diketones such as benzil, camphorquinone, α-naphthyl, acetonaphthene, p,p'-dimethoxybenzyl, p,p'-dichlorobenzylacetyl, pentanedione, 1,2-phenanthrenequinone, 1,4-phenanthrenequinone, 3,4-phenanthrenequinone, 9,10-phenanthrenequinone, and naphthoquinone, benzoin alkyl ethers such as benzoin, benzoin methyl ether, and benzoin ethyl ether, thioxanthone, 2-chlorothioxanthone, and 2-methylthioxanthone. Thioxanthones such as thioxanthone, 2-isopropylthioxanthone, 2-methoxythioxanthone, 2-hydroxythioxanthone, 2,4-diethylthioxanthone, and 2,4-diisopropylthioxanthone; benzophenones such as benzophenone, p-chlorobenzophenone, and p-methoxybenzophenone; 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, and 2,6-dimethoxybenzoyldiphenylphosphine oxide. acylphosphine oxides such as bis(2,6-dimethoxybenzoyl)phenylphosphine oxide, α-aminoacetophenones such as 2-benzyl-dimethylamino-1-(4-morpholinophenyl)-butanone-1,2-benzyl-diethylamino-1-(4-morpholinophenyl)-propanone-1, ketals such as benzyl dimethyl ketal, benzyl diethyl ketal, and benzyl (2-methoxyethyl ketal), 3-(4-methoxybenzoyl)coumarin, 3-benzoyl-5,7-dimethicone coumarins such as 3,3'-dihydroxycoumarin, 3,3'-carbonylbis(7-diethylaminocoumarin), and 3,3'-carbonylbis(7-dibutylaminocoumarin); titanocenes such as bis(cyclopentadienyl)-bis[2,6-difluoro-3-(1-pyrrolyl)phenyl]-titanium, bis(cyclopentadienyl)-bis(pentanefluorophenyl)-titanium, and bis(cyclopentadienyl)-bis(2,3,5,6-tetrafluoro-4-disiloxyphenyl)-titanium, but are not limited to these.

[0093] Specific examples of the photopolymerization accelerator include N,N-dimethylaniline, N,N-diethylaniline, N,N-di-n-butylaniline, N,N-dibenzylaniline, N,N-dimethyl-p-toluidine, N,N-dimethyl-m-toluidine, N,N-diethyl-p-toluidine, p-bromo-N,N-dimethylaniline, m-chloro-N,N-dimethylaniline, p-dimethylaminobenzaldehyde, p-dimethylaminoacetophenone, p-dimethylaminobenzoic acid, ethyl p-dimethylaminobenzoate, isoamyl p-dimethylaminobenzoate, N,N-dimethylanthranilic acid methyl ester, N,N-dihydroxyethylaniline, N,N-dihydroxyethyl-p-toluidine, p-dimethylaminophenyl alcohol, p-dimethylaminostyrene, N,N-dimethyl-3,5-xylidine, 4-dimethylaminopyridine, N,N-dimethyl -α-Naphthylamine, N,N-dimethyl-β-naphthylamine, triethanolamine, tributylamine, tripropylamine, triethylamine, N-methyldiethanolamine, N-ethyldiethanolamine, N,N-dimethylhexylamine, N,N-dimethyldodecylamine, N,N-dimethylstearylamine, N,N-dimethylaminoethyl (meth)acrylate, N,N-diethylaminoethyl (meth)acrylate tertiary amines such as 2,2'-(n-butylimino)diethanol, secondary amines such as N-phenylglycine, barbituric acids such as 5-butylbarbituric acid, 1-benzyl-5-phenylbarbituric acid, 1,3,5-trimethylbarbituric acid, sodium 1,3,5-trimethylbarbiturate, and calcium 1,3,5-trimethylbarbiturate, 2,4,6-tris(trichloromethyl)-s-triazine, 2-phenyl-4,6-bis(trichloromethyl)-s-triazine, 2-(p-chlorophenyl)-4,6-bis(trichloromethyl)-s-triazine, and 2-(4-biphenylyl)-4,Triazine compounds such as 6-bis(trichloromethyl)-s-triazine, diphenyliodonium chloride, diphenyliodonium hexafluorophosphate, diphenyliodonium hexafluoroantimonate, diphenyliodonium tetrafluoroborate, diphenyliodonium tetrakis(pentafluorophenyl)borate, bis-(4-methylphenyl)iodonium hexafluorophosphate, bis-(4-methylphenyl)iodonium hexafluoroantimonate, bis-(4-methylphenyl)iodonium tetrakis(pentafluorophenyl)borate, bis(4-tert-butylphenyl)iodonium hexafluoroantimonate ... Examples of suitable iodonium compounds include, but are not limited to, diaryliodonium salts such as dioctyl)iodonium tetrakis(pentafluorophenyl)borate, tin compounds such as dibutyltin diacetate, dibutyltin dilaurate, dioctyltin dilaurate, dioctyltin dibasate, dioctyltin bis(mercaptoacetic acid isooctyl ester) salt, and tetramethyl-1,3-diacetoxydistannoxane, aldehyde compounds such as lauryl aldehyde and terephthalaldehyde, and sulfur-containing compounds such as dodecyl mercaptan, 2-mercaptobenzoxazole, 1-decanethiol, and thiosalicylic acid.

[0094] Furthermore, in order to improve the photopolymerization promoting ability, it is effective to add, in addition to the above photopolymerization accelerators, oxycarboxylic acids such as citric acid, malic acid, tartaric acid, glycolic acid, gluconic acid, α-oxyisobutyric acid, 2-hydroxypropanoic acid, 3-hydroxypropanoic acid, 3-hydroxybutanoic acid, 4-hydroxybutanoic acid, and dimethylolpropionic acid, but the addition is not limited to these.

[0095] These polymerization initiators (f) can be used alone or in combination, regardless of the polymerization mode or method. These polymerization initiators (f) may be subjected to secondary treatment, such as encapsulation in microcapsules, if necessary, without any problems.

[0096] The (f) polymerization initiator is preferably contained in an amount of 0.01% by mass to 10% by mass, and more preferably 0.1% by mass to 5% by mass, based on the total amount of the dental resin-reinforced glass ionomer cement composition of the present invention. If the content of the (f) polymerization initiator is less than 0.01% by mass, the curing property may be impaired and the mechanical properties may be reduced. If the content of the (f) polymerization initiator is more than 10% by mass, the storage stability may be reduced.

[0097] <(g) Organic-inorganic composite filler> The dental resin-reinforced glass ionomer cement composition of the present invention preferably contains (g) an organic-inorganic composite filler to further improve mixability while maintaining the effect of (e) the porous inorganic filler in reducing stringiness of the mixed product. The (g) organic-inorganic composite filler that can be used in the dental resin-reinforced glass ionomer cement composition of the present invention is a composite particle consisting of an organic portion formed by hardening a polymerizable monomer and an inorganic portion contained in the form of an inorganic filler, and the inorganic filler is present in a dispersed state in the hardened polymerizable monomer. The (g) organic-inorganic composite filler can be obtained by mixing a polymerizable monomer containing a polymerization initiator and an inorganic filler in a state as uniform as possible, then hardening the polymerizable monomer and, if necessary, grinding the hardened product.

[0098] The polymerizable monomer that can be used to produce the (g) organic-inorganic composite filler is not particularly limited in its molecular structure, and the same polymerizable monomer as the (d) polymerizable monomer described above can be used.

[0099] The content of the polymerizable monomer contained in the raw materials of the (g) organic-inorganic composite filler is preferably 15% by mass or more and 90% by mass or less, more preferably 15% by mass or more and 60% by mass or less. If the content of the polymerizable monomer in the (g) organic-inorganic composite filler is less than 15% by mass, the inorganic filler may not be sufficiently dispersed in the organic-inorganic composite filler, and the mechanical properties of the organic-inorganic composite filler itself may be reduced. On the other hand, if the content of the polymerizable monomer exceeds 90% by mass, the wear resistance of the dental resin-reinforced glass ionomer cement composition of the present invention may be reduced.

[0100] Next, we will explain polymerization initiators that can be used in the production of (g) organic-inorganic composite filler. There are no particular limitations on the polymerization initiator, and known polymerization initiators such as thermal polymerization initiators, chemical polymerization initiators, and photopolymerization initiators can be used. Among these, it is preferable to use thermal polymerization initiators because they provide excellent production efficiency for (g) organic-inorganic composite filler. Suitable thermal polymerization initiators include organic peroxides such as benzoyl peroxide and azo compounds such as azobisisobutyronitrile. These polymerization initiators can be used alone or in combination, regardless of the polymerization mode or method. There are no particular limitations on the amount of polymerization initiator added, but it is generally 0.1 to 10 parts by mass per 100 parts by mass of all polymerizable monomers used in the production of (g) organic-inorganic composite filler.

[0101] Next, inorganic fillers that can be used in the production of (g) organic-inorganic composite filler will be described. The constituent elements of the inorganic filler are not particularly limited, and known inorganic fillers can be used. Specific examples of inorganic fillers include inorganic oxides such as silica, alumina, titania, zirconia, strontium oxide, barium oxide, yttrium oxide, lanthanum oxide, and ytterbium oxide; inorganic composite oxides such as silica-zirconia, silica-titania, silica-titania-barium oxide, and silica-titania-zirconia; fused silica, quartz, glasses such as aluminosilicate glass, fluoroaluminosilicate glass, borosilicate glass, aluminoborate glass, and boroaluminosilicate glass; and metal fluorides such as calcium fluoride, barium fluoride, strontium fluoride, yttrium fluoride, lanthanum fluoride, and ytterbium fluoride.

[0102] The shape of these inorganic fillers is not particularly limited, and they may be any shape such as spherical, needle-like, plate-like, crushed, or scale-like, and there is no problem even if they are aggregates of these. The inorganic fillers listed above are not limited to these, and they may be used alone or in combination.

[0103] While there are no particular limitations on the particle size of the inorganic filler, considering the balance of various properties of the dental resin-reinforced glass ionomer cement composition of the present invention, it is preferable that the 50% particle size (D50) be 0.005 μm or more and 3 μm or less. If the 50% particle size (D50) of the inorganic filler is less than 0.005 μm, it will be impossible to highly fill the (g) organic-inorganic composite filler with the inorganic filler, and the abrasion resistance of the dental resin-reinforced glass ionomer cement composition of the present invention may be reduced. Furthermore, if the 50% particle size (D50) of the inorganic filler exceeds 3 μm, the polishing ability of the dental resin-reinforced glass ionomer cement composition of the present invention may be reduced, and a smooth surface may not be obtained. Note that the (g) organic-inorganic composite filler used in the dental resin-reinforced glass ionomer cement composition of the present invention may be composed solely of an inorganic filler with a 50% particle size (D50) of 0.005 μm or more and 3 μm or less.

[0104] These inorganic fillers are preferably subjected to a surface treatment to be hydrophobic. This surface treatment enables a high loading of the inorganic filler in the organic-inorganic composite filler, thereby improving the mechanical properties of the organic-inorganic composite filler itself. There are no particular limitations on the surface treatment agent that can be used for the surface treatment of the inorganic filler, and known agents such as organosilicon compounds, organozirconium compounds, organotitanium compounds, and organoaluminum compounds can be used, but organosilicon compounds are the most commonly used. Specific examples of organosilicon compounds include, but are not limited to, methyltrimethoxysilane, ethyltrimethoxysilane, methoxytripropylsilane, propyltriethoxysilane, hexyltrimethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltrichlorosilane, vinyltri(β-methoxyethoxy)silane, 3-(meth)acryloyloxypropyltrimethoxysilane, 8-(meth)acryloyloxyoctyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, methyltrichlorosilane, phenyltrichlorosilane, trimethylsilyl isocyanate, vinylsilyl triisocyanate, phenylsilyl triisocyanate, and hexamethyldisilazane. These surface treatment agents can be used alone or in combination. Furthermore, there are no particular limitations on the surface treatment method, and known methods can be used. Furthermore, there is no particular limitation on the amount of the surface treatment agent relative to the inorganic filler when performing the surface treatment, and it may be adjusted appropriately depending on the particle size of the inorganic filler, etc.

[0105] The content of inorganic filler contained in the raw materials of (g) organic-inorganic composite filler is preferably 10% by mass or more and 85% by mass or less, more preferably 40% by mass or more and 85% by mass or less. If the content of inorganic filler in (g) organic-inorganic composite filler is less than 10% by mass, the abrasion resistance of the dental resin-reinforced glass ionomer cement composition of the present invention may decrease. On the other hand, if the content of inorganic filler exceeds 85% by mass, the dispersion of the inorganic filler in the organic-inorganic composite filler may become insufficient, and the mechanical properties of the organic-inorganic composite filler itself may decrease. Note that (g) organic-inorganic composite filler used in the dental resin-reinforced glass ionomer cement composition of the present invention may also contain 10% by mass or more and 85% by mass or less of inorganic filler having a 50% particle size (D50) of 0.005 μm or more and 3 μm or less. The dental resin-reinforced glass ionomer cement composition of the present invention may contain, as the (g) organic-inorganic composite filler, only an organic-inorganic composite filler in which the content of inorganic filler contained in the raw materials is 10% by mass or more and 85% by mass or less.The dental resin-reinforced glass ionomer cement composition of the present invention may contain, as the (g) organic-inorganic composite filler, only an organic-inorganic composite filler containing 10% by mass or more and 85% by mass or less of inorganic filler having a 50% particle size (D50) of 0.005 μm or more and 3 μm or less.

[0106] Next, a method for producing the (g) organic-inorganic composite filler will be described using a thermal polymerization initiator as an example. The (g) organic-inorganic composite filler is produced through the following main steps, steps 1) to 4). Step 1) is a step of mixing the components constituting the organic-inorganic composite filler, such as a polymerizable monomer, a thermal polymerization initiator, and an inorganic filler, to obtain a mixture. Step 2) is a step of applying heat to the mixture to polymerize the polymerizable monomer and obtain a cured product. Step 3) is a step of optionally pulverizing the cured product to obtain an organic-inorganic composite filler. Step 4) is a step of optionally surface-treating the organic-inorganic composite filler. For the dental resin-reinforced glass ionomer cement composition of the present invention, the pulverized organic-inorganic composite filler obtained in step 3) may be used as is, or the surface-treated organic-inorganic composite filler obtained in step 4) may be used. Furthermore, if the organic-inorganic composite filler is already in the form of fine particles rather than agglomerates at the stage of step 2), it may be used as is as the organic-inorganic composite filler. Furthermore, the organic-inorganic composite filler may be surface-treated in step 4) before use.

[0107] Examples of methods for obtaining a mixture of the components in step 1 include, but are not limited to, a method of mixing the components, such as a polymerizable monomer, a thermal polymerization initiator, and an inorganic filler, using a kneader; a method of agglomerating the inorganic filler to obtain pore-containing aggregates of several micrometers to several tens of micrometers, then immersing the aggregated filler in a solution of a thermal polymerization initiator and a polymerizable monomer dissolved in an organic solvent to form a slurry; and then removing the organic solvent at low temperature and under reduced pressure to allow the polymerizable monomer to penetrate and coat the interior and surface of the aggregated filler, thereby mixing the components; or a method of press-molding the inorganic filler to obtain an inorganic filler molded body, then immersing the molded body in a polymerizable monomer containing a thermal polymerization initiator, thereby allowing the polymerizable monomer to penetrate the interior of the molded body and mix the components. In addition, in this process, by dissolving a surface treatment agent such as the aforementioned organosilicon compound in the polymerizable monomer, surface treatment of the inorganic filler and mixing of the components can be performed simultaneously. This eliminates the need for a surface treatment of the inorganic filler before mixing the components.

[0108] In step 2) of obtaining a cured product, the polymerization temperature and polymerization time can be adjusted as appropriate depending on the properties of the thermal polymerization initiator used and on the heat-induced discoloration of the organic-inorganic composite filler and the amount of residual unpolymerized monomer, but generally the polymerization temperature is 70°C or higher and 150°C or lower, and the polymerization time is several minutes to several hours. Furthermore, polymerization conditions can be selected as appropriate depending on the polymerization method, such as polymerization in air, polymerization in an inert gas atmosphere such as nitrogen or argon, polymerization under normal pressure, or polymerization under pressure.

[0109] In step 3) of obtaining an organic-inorganic composite filler by pulverization, a pulverization method similar to that used in producing the aforementioned (a) acid-reactive glass powder can be used. The 50% particle size (D50) of the (g) organic-inorganic composite filler is not particularly limited, and the particle size can be adjusted appropriately depending on the desired properties to be imparted to the dental resin-reinforced glass ionomer cement composition of the present invention. However, the 50% particle size (D50) is preferably 1 μm or more and 50 μm or less. If the 50% particle size (D50) of the (g) organic-inorganic composite filler is less than 1 μm, mixing properties may be impaired, and if it exceeds 50 μm, mechanical properties may be impaired. The dental resin-reinforced glass ionomer cement composition of the present invention may contain only organic-inorganic composite fillers having an average particle size of 1 μm or more and 50 μm or less as the (g) organic-inorganic composite filler.

[0110] In step 4) of performing a surface treatment on the organic-inorganic composite filler, the same surface treatment agent as that which can be used for the surface treatment of the inorganic filler described above can be used. Furthermore, as with the surface treatment of the inorganic filler, a known method can be used for the surface treatment. Furthermore, the amount of the surface treatment agent relative to the organic-inorganic composite filler when performing the surface treatment is not particularly limited and may be adjusted appropriately depending on the particle size of the organic-inorganic composite filler, but is preferably 0.1 parts by mass or more and 5 parts by mass or less per 100 parts by mass of the organic-inorganic composite filler.

[0111] When the dental resin-reinforced glass ionomer cement composition of the present invention contains (g) organic-inorganic composite filler, it is preferable to balance the content of (e) porous inorganic filler. That is, the total content of (e) porous inorganic filler and (g) organic-inorganic composite filler is preferably 2% by mass or more and 20% by mass or less of the total dental resin-reinforced glass ionomer cement composition of the present invention, and the mass ratio of the content of (e) porous inorganic filler to the content of (g) organic-inorganic composite filler [(g) organic-inorganic composite filler / (e) porous inorganic filler] is preferably 0.5 to 2.5. By containing (e) porous inorganic filler and (g) organic-inorganic composite filler within this range, the viscosity of the kneaded product is kept low and kneadability is further improved without adversely affecting other properties. Furthermore, the total content is more preferably 3% by mass or more and 15% by mass or less. Furthermore, the mass ratio is more preferably 0.8 to 2.0.

[0112] If the total content is less than 2% by mass, the effect of reducing stringiness of the kneaded product may not be sufficiently obtained. On the other hand, if the total content exceeds 20% by mass, the kneading property, mechanical properties, and transparency may be reduced. Also, if the mass ratio is less than 0.5, the viscosity of the kneaded product may not be kept low, and the kneading property may be deteriorated. On the other hand, if the mass ratio exceeds 2.5, the mechanical properties and transparency may be reduced.

[0113] <Other ingredients> The dental resin-reinforced glass ionomer cement composition of the present invention can optionally contain an acidic compound to adjust the working time and setting time, as long as the acidic compound does not adversely affect various properties. Specific examples of acidic compounds include carboxylic acid compounds such as tartaric acid, citric acid, maleic acid, fumaric acid, malic acid, oxalic acid, malonic acid, ascorbic acid, mesaconic acid, itaconic acid, oxaloacetic acid, glutaric acid, aconitic acid, tricarballylic acid, 1-butene-1,2,4-tricarboxylic acid, and 3-butene-1,2,3-tricarboxylic acid, and phosphate compounds such as phosphoric acid, pyrophosphoric acid, and tripolyphosphoric acid, but are not limited to these. Furthermore, these acidic compounds may be partially neutralized with a basic compound without any problems. The basic compound may be the same as the compound that can be used to neutralize (b) the polyalkenoic acid. These acidic compounds may be used alone or in combination. When an acidic compound is contained in the dental resin-reinforced glass ionomer cement composition of the present invention, the acidic compound is preferably contained in an amount of 0.1% by mass to 15% by mass of the entire composition. However, the dental resin-reinforced glass ionomer cement composition of the present invention may not contain an acidic compound.

[0114] Furthermore, the dental resin-reinforced glass ionomer cement composition of the present invention can optionally contain a surfactant to adjust the initial compatibility and properties of the kneaded material between the powder material and liquid material, or the first paste and second paste, etc., as long as the surfactant does not adversely affect various properties. The surfactant that can be used in the dental resin-reinforced glass ionomer cement composition of the present invention may be either an ionic surfactant or a nonionic surfactant.

[0115] Specific examples of ionic surfactants include anionic surfactants such as metal salts of aliphatic carboxylic acids (e.g., sodium stearate), sulfated metal salts of aliphatic carboxylic acids (e.g., sodium dioctyl sulfosuccinate), and metal salts of higher alcohol sulfates (e.g., sodium stearyl sulfate). Cationic surfactants include adducts of higher alkylamines and ethylene oxide, amines prepared from lower amines, and alkyltrimethylammonium salts (e.g., lauryltrimethylammonium chloride). Amphoteric surfactants include metal salts of higher alkylaminopropionic acids (e.g., sodium stearylaminopropionate), and betaines (e.g., lauryldimethylbetaine).

[0116] Examples of nonionic surfactants include polyethylene glycol or polypropylene glycol surfactants in which ethylene oxide or propylene oxide is added to higher alcohols, alkylphenols, fatty acids, higher aliphatic amines, aliphatic amides, etc., as well as polyhydric alcohols, diethanolamines, and polyhydric alcohols in which sugars and fatty acids are ester-bonded.

[0117] The surfactants listed above are not limited to these, and may be used alone or in combination. When a surfactant is contained in the dental resin-reinforced glass ionomer cement composition of the present invention, the surfactant is preferably contained in an amount of 0.001% by mass or more and 5% by mass or less based on the total mass of the composition. However, the dental resin-reinforced glass ionomer cement composition of the present invention may not contain a surfactant.

[0118] Furthermore, the dental resin-reinforced glass ionomer cement composition of the present invention may optionally contain a non-porous, non-acid-reactive powder for the purpose of adjusting the operability, mechanical properties, or hardening properties, as long as the powder does not adversely affect the various properties.

[0119] The non-acid-reactive powder having no pores that can be used in the dental resin-reinforced glass ionomer cement composition of the present invention is not particularly limited as long as it does not contain an element that reacts with the acidic group of (b) the polyalkenoic acid. Examples of non-acid-reactive powders having no pores include those known in the dental field, such as inorganic fillers and organic fillers, which can be used alone or in combination. Among these, inorganic fillers are particularly preferred. Furthermore, the shape of these non-acid-reactive powders having no pores is not particularly limited, and they may be spherical, acicular, plate-like, crushed, scale-like, or any other shape. The 50% particle size (D50) of these non-acid-reactive powders is not particularly limited, but is preferably 0.001 μm or more and 30 μm or less.

[0120] Specific examples of non-porous inorganic fillers include, but are not limited to, quartz, amorphous silica, ultrafine silica particles, various glasses that do not contain elements that react with acidic groups (including glasses produced by melting methods, synthetic glasses by the sol-gel method, glasses produced by gas-phase reactions, etc.), silicon nitride, silicon carbide, boron carbide, etc. Furthermore, these non-porous inorganic fillers can be used alone or in combination.

[0121] When the dental resin-reinforced glass ionomer cement composition of the present invention contains a non-acid-reactive powder having no pores, the content of the non-acid-reactive powder is preferably 0.001% by mass or more and 20% by mass or less based on the total mass of the composition. However, the dental resin-reinforced glass ionomer cement composition of the present invention may not contain the non-acid-reactive powder having no pores.

[0122] Furthermore, when the dental resin-reinforced glass ionomer cement composition of the present invention is in a paste form, a thickener can be optionally added to adjust the paste properties within a range that does not adversely affect various properties.

[0123] The thickener that can be used in the dental resin-reinforced glass ionomer cement composition of the present invention may be either an inorganic or organic thickener, such as fumed silica, calcium carbonate, calcium silicate, magnesium silicate, or clay minerals such as saponite, montmorillonite, beidellite, vermiculite, sauconite, stevensite, hectorite, smectite, tietite, and sepiolite.

[0124] Examples of organic thickeners include methyl cellulose, hydroxyethyl cellulose, hydroxymethyl cellulose, hydroxypropyl cellulose, carboxymethyl cellulose, sodium carboxymethyl cellulose, calcium carboxymethyl cellulose, carboxypolymethylene, sodium alginate, propylene glycol alginate, sodium polyacrylate, starch, sodium starch glycolate, starch phosphate ester, polyvinylpyrrolidone, carboxyvinyl polymer, khaya gum, gum arabic, karaya gum, guar gum, and xanthan gum.

[0125] The thickeners listed above are not limited to these, and may be used alone or in combination. When a thickener is contained in the dental resin-reinforced glass ionomer cement composition of the present invention, the thickener is preferably contained in an amount of 0.001% by mass to 10% by mass in the paste. However, the dental resin-reinforced glass ionomer cement composition of the present invention may not contain a thickener.

[0126] Furthermore, the dental resin-reinforced glass ionomer cement composition of the present invention may optionally contain components such as polymerization inhibitors, chain transfer agents, discoloration inhibitors, ultraviolet absorbers, preservatives, antibacterial agents, colorants, fluorescent agents, inorganic fiber materials, organic fiber materials, and other conventionally known additives, as needed.

[0127] The dental resin-reinforced glass ionomer cement composition of the present invention can be provided in various forms, such as powder / liquid, paste / paste, paste / powder, or paste / liquid, as long as (a) the acid-reactive glass powder and (b) the polyalkenoic acid do not coexist in the presence of (c) water.

[0128] In the dental resin-reinforced glass ionomer cement composition of the present invention, it is preferable to shorten the treatment time by shortening the time until shaping can begin, for example, by adjusting the blending amounts of the above-described components. To shorten the treatment time, the time until shaping can begin is preferably within 40 seconds, more preferably within 30 seconds, and even more preferably within 20 seconds.

[0129] The dental resin-reinforced glass ionomer cement composition of the present invention can be used for a wide range of applications in dental treatment, such as as a filling material and a bonding material, as well as a pit and fissure sealant, a lining material, a core construction material, and a tooth surface coating material. [Example]

[0130] The present invention will be specifically explained below with reference to examples and comparative examples, but the present invention is not limited to these examples. Components (a) to (g) and other components used to prepare the dental resin-reinforced glass ionomer cement compositions of the examples and comparative examples, as well as their abbreviations and production methods, are as follows:

[0131] [(a) Acid-reactive glass powder] G1: Acid-reactive glass powder 1 (G1) (fluoroaluminosilicate glass powder, 50% particle size (D50): 2.5 μm) G2: Acid-reactive glass powder 2 (G2) (silane-treated fluoroaluminosilicate glass powder, 50% particle size (D50): 2.5 μm) G3: Acid-reactive glass powder 3 (G3) (silane-treated fluoroaluminosilicate glass powder, 50% particle size (D50): 30 μm) G4: Acid-reactive glass powder 4 (G4) (silane-treated fluoroaluminosilicate glass powder, 50% particle size (D50): 0.45 μm)

[0132] [(b) Polyalkenoic acid] PCA1: Acrylic acid homopolymer powder (weight average molecular weight: 50,000) PCA2: Acrylic acid homopolymer powder (weight average molecular weight: 15,000) PCA3: Acrylic acid homopolymer powder (weight average molecular weight: 350,000)

[0133] [(c)Water] ·IEW: Ion-exchanged water

[0134] [(d) Polymerizable Monomer] GDMA: Glycerol-1,3-dimethacrylate (hydroxyl group-containing polymerizable monomer) HEMA: 2-hydroxyethyl methacrylate (hydroxyl group-containing polymerizable monomer) 4-AET: 4-acryloxyethyltrimellitic acid (polymerizable monomer containing an acidic group) FAM: tetrafunctional acrylamide monomer ("FOM-03006" (Fujifilm Wako Pure Chemical Industries, Ltd.)) Bis-GMA: Bisphenol A diglycidyl methacrylate (hydroxyl group-containing polymerizable monomer)

[0135] [(e) Porous inorganic filler] PIF1: Porous inorganic filler (SiO2: 80% by mass, ZrO2: 20% by mass, 50% particle size (D50): 2.0 μm, pore volume: 0.08 cc / g, specific surface area: 15 m 2 / g) PIF2: Porous inorganic filler (SiO2: 80% by mass, ZrO2: 20% by mass, 50% particle size (D50): 3.0 μm, pore volume: 0.20 cc / g, specific surface area: 135 m 2 / g) PIF3: Porous inorganic filler (SiO2: 80% by mass, ZrO2: 20% by mass, 50% particle size (D50): 4.0 μm, pore volume: 0.30 cc / g, specific surface area: 200 m 2 / g) PIF4: Porous inorganic filler (SiO2: 100% by mass, 50% particle size (D50): 9.0 μm, pore volume: 0.80 cc / g, specific surface area: 200 m 2 / g) PIF5: Surface-treated porous inorganic filler (SiO2: 80% by mass, ZrO2: 20% by mass, 50% particle size (D50): 3.0 μm, pore volume: 0.19 cc / g, specific surface area: 133 m 2 / g) PIF6: Porous inorganic filler (SiO2: 94% by mass, TiO2: 6% by mass, 50% particle size (D50): 2.9 μm, pore volume: 0.21 cc / g, specific surface area: 173 m 2 / g) PIF7: Porous inorganic filler (SiO2: 70% by mass, ZrO2: 30% by mass, 50% particle size (D50): 2.9 μm, pore volume: 0.19 cc / g, specific surface area: 161 m 2 / g) PIF8: Porous inorganic filler (SiO2: 65% by mass, ZrO2: 35% by mass, 50% particle size (D50): 2.9 μm, pore volume: 0.17 cc / g, specific surface area: 149 m 2 / g)

[0136] [(f) Polymerization initiator] KPS: Potassium peroxodisulfate TSNa: Sodium p-toluenesulfinate AA: L(+)-ascorbic acid CQ: dl-camphorquinone

[0137] [(g) Organic-inorganic composite filler] O1: Organic-inorganic composite filler 1 (50% particle size (D50): 30 μm, inorganic filler content: 50% by mass, inorganic filler primary average particle size: 16 nm) O2: Organic-inorganic composite filler 2 (50% particle size (D50): 25 μm, inorganic filler content: 25% by mass, inorganic filler primary average particle size: 16 nm) O3: Organic-inorganic composite filler 3 (50% particle size (D50): 20 μm, inorganic filler content: 50% by mass, 50% inorganic filler particle size (D50): 0.5 μm) O4: Organic-inorganic composite filler 4 (50% particle size (D50): 55 μm, inorganic filler content: 75% by mass, 50% inorganic filler particle size (D50): 4 μm)

[0138] [others] Fuselex X: Crushed silica filler (non-acid-reactive powder with no pores, 50% particle size (D50): 3.0 μm, pore volume: less than 0.01 cc / g) Aerosil R972: Spherical silica filler (thickener, primary average particle size 16 nm, pore volume: less than 0.01 cc / g)

[0139] [(a) Preparation of Acid-Reactive Glass Powder] [Production of Acid-Reactive Glass Powder 1 (G1)] Various raw materials, including silica, alumina, aluminum phosphate, sodium fluoride, and strontium carbonate (glass composition: 26.4% by mass of SiO, 29.3% by mass of AlO, 20.5% by mass of SrO, 10.9% by mass of PO, 2.5% by mass of NaO, and 10.4% by mass of F), were mixed and then melted in a melting furnace at 1400°C. The melt was removed from the furnace and quenched in water to obtain fluoroaluminosilicate glass. The resulting fluoroaluminosilicate glass was crushed to a 50% particle size (D50) of 2.5 μm to obtain acid-reactive glass powder 1 (G1). The 50% particle size (D50) was measured using a laser diffraction / scattering particle size analyzer (Microtrac MT3300EXII, manufactured by Microtrac Bell).

[0140] [Production of Acid-Reactive Glass Powder 2 (G2)] A surface treatment solution (total mass: 9.2 parts by mass) was prepared by mixing 1.0 part by mass of 3-methacryloyloxypropyltrimethoxysilane, 0.1 part by mass of ion-exchanged water, and 8.1 parts by mass of anhydrous ethanol. This surface treatment solution was dry-mixed with 100 parts by mass of acid-reactive glass powder 1 (G1), and then heat-treated at 110°C for 5 hours using a hot air dryer to obtain acid-reactive glass powder 2 (G2).

[0141] [Production of Acid-Reactive Glass Powder 3 (G3)] Fluoroaluminosilicate glass was obtained in the same manner as for acid-reactive glass powder 1 (G1). The obtained fluoroaluminosilicate glass was pulverized until the 50% particle size (D50) was 30 μm, yielding an acid-reactive glass powder. The 50% particle size (D50) was measured using a laser diffraction / scattering particle size distribution analyzer (Microtrac MT3300EXII, manufactured by Microtrac Bell). Next, 1.0 part by mass of 3-methacryloyloxypropyltrimethoxysilane, 0.1 part by mass of ion-exchanged water, and 8.1 parts by mass of anhydrous ethanol were mixed to prepare a surface treatment liquid (total mass: 9.2 parts by mass). This surface treatment liquid and 100 parts by mass of the acid-reactive glass powder were dry-mixed and then heat-treated at 110°C for 5 hours using a hot air dryer, yielding acid-reactive glass powder 3 (G3).

[0142] [Production of Acid-Reactive Glass Powder 4 (G4)] Fluoroaluminosilicate glass was obtained in the same manner as for acid-reactive glass powder 1 (G1). The obtained fluoroaluminosilicate glass was pulverized until the 50% particle size (D50) was 0.45 μm, yielding an acid-reactive glass powder. The 50% particle size (D50) was measured using a laser diffraction / scattering particle size distribution analyzer (Microtrac MT3300EXII, manufactured by Microtrac Bell). Next, 3.0 parts by mass of 3-methacryloyloxypropyltrimethoxysilane, 0.3 parts by mass of ion-exchanged water, and 15.0 parts by mass of anhydrous ethanol were mixed to prepare a surface treatment liquid (total mass: 18.3 parts by mass). 100 parts by mass of this surface treatment liquid and the acid-reactive glass powder were dry-mixed and then heat-treated at 110°C for 5 hours using a hot air dryer, yielding acid-reactive glass powder 4 (G4).

[0143] [Production of surface-treated porous inorganic filler (PIF5)] A surface treatment solution (total mass: 9.2 parts by mass) was prepared by mixing 0.3 parts by mass of 3-methacryloyloxypropyltrimethoxysilane, 0.1 parts by mass of ion-exchanged water, and 8.8 parts by mass of anhydrous ethanol. This surface treatment solution was dry-mixed with 100 parts by mass of porous inorganic filler (PIF2), and then heat-treated at 110°C for 5 hours using a hot air dryer to obtain surface-treated porous inorganic filler (PIF5).

[0144] [Production of organic-inorganic composite filler 1 (O1)] A resin mixture was prepared by mixing 50 parts by weight of urethane dimethacrylate (UDMA), 50 parts by weight of neopentyl glycol dimethacrylate, and 0.1 parts by weight of benzoyl peroxide (BPO). 50 parts by weight of this resin mixture and 50 parts by weight of Aerosil R972 were mixed until homogeneous, and the mixture was heated at 100°C for 4 hours under a nitrogen atmosphere to obtain a cured product. The cured product was then pulverized to a 50% particle size (D50) of 30 μm to obtain organic-inorganic composite filler 1 (O1). The 50% particle size (D50) was measured using a laser diffraction / scattering particle size distribution analyzer (Microtrac MT3300EXII, manufactured by Microtrac Bell).

[0145] [Production of organic-inorganic composite filler 2 (O2)] A resin mixture was obtained by mixing 75 parts by weight of UDMA, 25 parts by weight of ethylene glycol dimethacrylate, and 0.2 parts by weight of BPO. 75 parts by weight of this resin mixture was mixed with 25 parts by weight of Aerosil R972 until homogeneous, and then the mixture was heated at 100°C for 4 hours under a nitrogen atmosphere to obtain a cured product. The cured product was then pulverized to a 50% particle size (D50) of 25 μm to obtain organic-inorganic composite filler 2 (O2). The 50% particle size (D50) was measured using a laser diffraction / scattering particle size distribution analyzer (Microtrac MT3300EXII, manufactured by Microtrac Bell).

[0146] [Production of organic-inorganic composite filler 3 (O3)] A surface treatment solution (total mass: 17.0 parts by mass) was prepared by mixing 6.0 parts by mass of 3-methacryloyloxypropyltrimethoxysilane, 1.0 part by mass of ion-exchanged water, and 10.0 parts by mass of anhydrous ethanol. Fluoroaluminosilicate glass was prepared in the same manner as for acid-reactive glass powder 1 (G1), and the resulting fluoroaluminosilicate glass was pulverized to a 50% particle size (D50) of 0.5 μm, thereby obtaining a fluoroaluminosilicate glass powder. The surface treatment solution and 100 parts by mass of the fluoroaluminosilicate glass powder (50% particle size (D50): 0.5 μm) were dry mixed and then heat-treated at 110°C for 5 hours using a hot air dryer to obtain a surface-treated glass powder. 50 parts by mass of Bis-GMA, 50 parts by mass of triethylene glycol dimethacrylate, and 0.2 parts by mass of BPO were mixed to obtain a resin mixture. 50 parts by mass of this resin mixture and 50 parts by mass of the surface-treated glass powder were kneaded until homogeneous, and the kneaded mixture was heated at 100°C for 4 hours under a nitrogen atmosphere to obtain a cured product. The resulting cured product was pulverized to a 50% particle size (D50) of 20 μm to obtain organic-inorganic composite filler 3 (O3). The 50% particle size (D50) was measured using a laser diffraction / scattering particle size distribution analyzer (Microtrac MT3300EXII, manufactured by Microtrac Bell).

[0147] [Production of organic-inorganic composite filler 4 (O4)] A surface treatment solution (total mass: 11.5 mass parts) was prepared by mixing 3.0 parts by mass of 3-methacryloyloxypropyltrimethoxysilane, 0.5 parts by mass of ion-exchanged water, and 8.0 parts by mass of anhydrous ethanol. Next, fluoroaluminosilicate glass was obtained in the same manner as for acid-reactive glass powder 1 (G1). The obtained fluoroaluminosilicate glass was pulverized until the 50% particle size (D50) was 4 μm, to obtain a fluoroaluminosilicate glass powder. The surface-treated solution was dry-mixed with 100 parts by weight of a fluoroaluminosilicate glass powder (50% particle size (D50): 4 μm) with the same components as acid-reactive glass powder 1 (G1), followed by heat treatment at 110°C for 5 hours using a hot air dryer to obtain a surface-treated glass powder. 50 parts by weight of Bis-GMA, 50 parts by weight of triethylene glycol dimethacrylate, and 0.2 parts by weight of BPO were mixed to obtain a resin mixture. 25 parts by weight of this resin mixture was kneaded with 75 parts by weight of the surface-treated glass powder until homogeneous, and the kneaded mixture was heated at 100°C for 4 hours under a nitrogen atmosphere to obtain a cured product. The resulting cured product was pulverized to a 50% particle size (D50) of 55 μm to obtain organic-inorganic composite filler 4 (O4). The 50% particle size (D50) was measured using a laser diffraction / scattering particle size distribution analyzer (Microtrac MT3300EXII, manufactured by Microtrac Bell).

[0148] [Preparation of powder and liquid materials, or first paste and second paste] The various components were mixed in the proportions shown in Tables 1 to 7 to prepare powder materials (Tables 1 to 4), liquid materials (Table 5), first paste (Table 6), and second paste (Table 7).

[0149] Powder composition (mass%) [Table 1]

[0150] Powder composition (mass%) [Table 2]

[0151] Powder composition (mass%) [Table 3]

[0152] Powder composition (mass%) [Table 4]

[0153] Liquid material composition (mass%) [Table 5]

[0154] First paste composition (mass%) [Table 6]

[0155] Second paste composition (mass%) [Table 7]

[0156] [Dental resin-reinforced glass ionomer cement composition] Dental resin-reinforced glass ionomer cement compositions for filling or luting (Examples 1 to 63, Comparative Examples 1 to 9) were prepared by combining the powder and liquid materials, or the first and second pastes, at the powder-liquid ratios or paste ratios (mass ratios) shown in Tables 8 to 12. The mixability, stringiness of the mixed product, time to start shaping, compressive strength, and contrast ratio were evaluated. For Examples 1 to 5, 8 to 10, 12 to 33, 36, 40, 43, 44, 46, 48, 50, 53, 55 to 63 and Comparative Examples 1, 4 to 6, and 9, which are compositions for filling, all of the above test items were evaluated. For Examples 6, 7, 11, 34, 35, 37 to 39, 41, 42, 45, 47, 49, 51, 52, and 54 and Comparative Examples 2, 3, 7, and 8, which are compositions for luting, all of the above test items except the time to start shaping were evaluated. The evaluation method is as follows.

[0157] [Mixability] In an environment of a temperature of 23±1°C and a humidity of 50±10%, the powder and liquid materials, or the first and second pastes, of the dental resin-reinforced glass ionomer cement compositions of the Examples or Comparative Examples were mixed using a plastic spatula in the proportions shown in Tables 8 to 12. The total amount of powder and liquid materials, or the first and second pastes, was 360 mg. The time taken from the start of mixing to the time until the mixture became homogeneous was measured. The above procedure was performed three times by three evaluators, and the average of the measurement results was evaluated based on the following evaluation criteria to determine the evaluation result for the measurement object. A rating of A, B, or C was used to determine whether the sample had good mixability. -Evaluation criteria- [Powder-liquid type] A: The time required for the kneaded material to become uniform is less than 40 seconds. B: The time required for the kneaded material to become uniform is 40 seconds or more and less than 50 seconds. C: The time required for the kneaded product to become uniform is 50 seconds or more and less than 55 seconds. D: The time required for the kneaded material to become uniform is 55 seconds or more, or the kneaded material is not uniform. [Paste type] A: The time required for the kneaded material to become uniform is less than 10 seconds. B: The time required for the kneaded material to become uniform is 10 seconds or more and less than 15 seconds. C: The time required for the kneaded product to become uniform is 15 seconds or more and less than 20 seconds. D: The time required for the kneaded material to become uniform is 20 seconds or more.

[0158] [Stringiness of the kneaded mixture] The powder and liquid materials, or the first and second pastes, of the dental resin-reinforced glass ionomer cement compositions of the Examples and Comparative Examples were mixed using a plastic spatula in the proportions shown in Tables 8 to 12 under an environment of 23±1°C and 50±10% humidity. The total amount of powder and liquid materials, or the first and second pastes, was 360 mg. Immediately after mixing, the mixture was filled into a plastic simulated cavity (a 4mm x 8mm x 2mm cavity simulating a Class I cavity), and the excess material was scraped off to create a flat surface. Ten seconds after mixing, the cylindrical tip (1.5mm diameter) of a metal instrument (MiCD Instrument, manufactured by Matsukaze) was vertically immersed 0.5mm into the mixture. The instrument was then gently withdrawn immediately. The degree of stringiness of the mixture was evaluated according to the following criteria. The above procedure was performed three times by three evaluators, and the most common evaluation result was taken as the evaluation result for the measurement object. If the evaluation result was A or B, it was determined that the kneaded material had little stringiness and good properties. -Evaluation criteria- A: It doesn't string. B: Slight stringiness. C: Significant stringiness.

[0159] [Possible time to start shaping] The powder and liquid materials, or the first and second pastes, of the dental resin-reinforced glass ionomer cement compositions of the Examples and Comparative Examples were mixed using a plastic spatula in the proportions shown in Tables 8 to 12 under conditions of 23±1°C and 50±10% humidity. The total amount of powder and liquid materials, or the first and second pastes, was 360 mg. Immediately after mixing, the mixture was filled into a plastic simulated cavity (a 4 mm x 8 mm x 2 mm cavity simulating a Class I cavity), and the excess material was scraped off to create a smooth surface. Starting 20 seconds after mixing was completed, the cylindrical tip (1.5 mm diameter) of a metal instrument (MiCD Instrument, manufactured by Matsukaze) was vertically immersed 0.5 mm into the mixture at 10-second intervals. The instrument was then gently withdrawn immediately, and the degree of stringiness of the mixture was observed. Starting from the end of mixing, the time until the stringiness of the kneaded material was reduced and the material was ready for shaping was measured. The above procedure was performed three times by three evaluators, and the measurement results were evaluated based on the following evaluation criteria, with the most frequently evaluated result being the evaluation result for the measurement subject. If the evaluation result was A, B, or C, it was determined that the material had an early shaping start time. -Evaluation criteria- A: 20 seconds after mixing is complete, the stringiness of the mixed material is reduced and shaping operations are possible. B: 30 seconds after mixing, the stringiness of the mixed material has decreased and it is now possible to perform shaping operations. C: 40 seconds after mixing, the stringiness of the mixed material has decreased and it is now possible to perform shaping operations. D: After mixing, the stringiness of the mixed material is reduced and shaping is possible after 50 seconds or more.

[0160] [Compression strength] The powder and liquid components, or the first and second pastes, of the dental resin-reinforced glass ionomer cement compositions of the Examples and Comparative Examples were mixed using a plastic spatula in the proportions shown in Tables 8 to 12 under an environment of 23±1°C and 50±10% humidity. The mixed mixture was filled into a stainless steel mold (cylindrical, inner diameter: 4 mm, height: 6 mm) and irradiated with light for 10 seconds using a dental polymerization light irradiator (Penbrite, manufactured by Shofu). The mixture was then placed in a thermo-hygrostat chamber at 37°C and 90% humidity or higher. After standing for 1 hour, the cured product was removed from the mold and used as a test specimen. The test specimen was immersed in 37°C ion-exchanged water for 24 hours after mixing, and the compressive strength of the specimen was measured using an Instron universal testing machine (Model: 5567A) at a crosshead speed of 1 mm / min in accordance with ISO 9917-1:2007. Each measurement was carried out five times, and the average of the measurement results was evaluated based on the following evaluation criteria to determine the evaluation result for the measurement object. If the evaluation result was A, B, or C, it was determined that the object had good mechanical properties. -Evaluation criteria- Filling Composition A: Compressive strength is 180 MPa or more. B: Compressive strength is 160 MPa or more and less than 180 MPa. C: Compressive strength is 150 MPa or more and less than 160 MPa. D: Compressive strength is less than 150 MPa. [Composition for cementing] A: Compressive strength is 100 MPa or more. B: Compressive strength is 80 MPa or more and less than 100 MPa. C: Compressive strength is 70 MPa or more and less than 80 MPa. D: Compressive strength is less than 70 MPa.

[0161] [Contrast ratio] The powder and liquid materials, or the first and second pastes, of the dental resin-reinforced glass ionomer cement compositions of the Examples and Comparative Examples were mixed using a plastic spatula in the proportions shown in Tables 8 to 12 under an environment of 23±1°C and 50±10% humidity. The mixed mixture was filled into a stainless steel ring mold (inner diameter: 12 mm, thickness: 1 mm) and irradiated for 10 seconds using a dental polymerization light irradiator (Penbrite, manufactured by Shofu). The mixture was then placed in a thermo-hygrostat chamber at 37°C and 90% humidity or higher. After standing for 1 hour, the cured product was removed from the mold and used as a test specimen. The test specimen was immersed in ion-exchanged water at 37°C for 24 hours after mixing. The Y value (Yw) of the test specimen on a white plate and the Y value (Yb) of the test specimen on a black plate were measured using a colorimeter (Spectra Photometer: CM-3500d). The contrast ratio was calculated by calculating the ratio (Yb / Yw). Each measurement was carried out three times, and the average of the measurement results was evaluated based on the following evaluation criteria to determine the evaluation result of the measurement object. If the evaluation result was A, B, or C, it was determined that the object had good transparency. -Evaluation criteria- A: The contrast ratio is less than 0.68. B: The contrast ratio is 0.68 or greater and less than 0.70. C: The contrast ratio is 0.70 or greater and less than 0.71. D: The contrast ratio is 0.71 or higher.

[0162] The compositions of the Examples and Comparative Examples were evaluated according to the above test methods, and the results are shown in Tables 8 to 12.

[0163] Evaluation results of Examples 1 to 15 [Table 8]

[0164] Evaluation results of Examples 16 to 30 [Table 9]

[0165] Evaluation results of Examples 31 to 45 [Table 10]

[0166] Evaluation results of Examples 46 to 60 [Table 11]

[0167] Evaluation results of Examples 61 to 63 and Comparative Examples 1 to 9 [Table 12]

[0168] <Evaluation results of the example: for filling> Examples 1 to 5, 8 to 10, 12 to 33, 36, 40, 43, 44, 46, 48, 50, 53, and 55 to 63 showed little stringiness immediately after mixing, allowing for shaping operations to be performed soon after filling into the simulated cavity. Furthermore, they also had good kneading properties, mechanical properties, and transparency, and possessed desirable properties as dental resin-reinforced glass ionomer cement compositions for filling. Among these, when both (e) porous inorganic filler and (g) organic-inorganic composite filler were contained within the preferred or more preferred ranges, better kneading properties were exhibited.

[0169] <Evaluation results of the example: for adhesion> Examples 6, 7, 11, 34, 35, 37-39, 41, 42, 45, 47, 49, 51, 52, and 54 showed little stringiness immediately after mixing. Furthermore, they also had good kneading properties, mechanical properties, and transparency, and possessed desirable properties as dental resin-reinforced glass ionomer cement compositions for luting. Among these, when both (e) porous inorganic filler and (g) organic-inorganic composite filler were contained within the preferred or more preferred ranges, better kneading properties were exhibited.

[0170] <Evaluation results of comparative examples> <Comparative Example 1> The dental resin-reinforced glass ionomer cement composition for filling of Comparative Example 1 does not contain (e) porous inorganic filler. As a result of evaluating Comparative Example 1, significant stringiness was observed immediately after mixing, and it took a long time before shaping operations became possible. <Comparative Example 2> The dental resin-reinforced glass ionomer cement composition for luting of Comparative Example 2 did not contain (e) porous inorganic filler. As a result of evaluating Comparative Example 2, significant stringiness was observed immediately after mixing. <Comparative Example 3> The dental resin-reinforced glass ionomer cement composition for luting of Comparative Example 3 had a low content of (e) porous inorganic filler. As a result of evaluating Comparative Example 3, significant stringiness was observed immediately after mixing. <Comparative Example 4> The dental resin-reinforced glass ionomer cement composition for filling of Comparative Example 4 had a high content of (e) porous inorganic filler. As a result of evaluating Comparative Example 4, it was found that the mixing properties were poor. <Comparative Example 5> The dental resin-reinforced glass ionomer cement composition for filling of Comparative Example 5 contains (a) acid-reactive glass powder (G3) with a large particle size instead of (e) porous inorganic filler. Evaluation of Comparative Example 5 showed that the compressive strength was low. <Comparative Example 6> The dental resin-reinforced glass ionomer cement composition for filling of Comparative Example 6 contained a non-acid-reactive powder without pores instead of the porous inorganic filler (e). Evaluation of Comparative Example 6 revealed that significant stringiness was observed immediately after mixing, a long time was required before shaping operations became possible, and the compressive strength was also low. <Comparative Examples 7 and 8> The dental resin-reinforced glass ionomer cement compositions for luting in Comparative Examples 7 and 8 did not contain (e) a porous inorganic filler, but contained only (g) an organic-inorganic composite filler. Evaluation of Comparative Examples 7 and 8 revealed that they had a high contrast ratio and were opaque. <Comparative Example 9> The dental resin-reinforced glass ionomer cement composition for filling of Comparative Example 9 did not contain (e) a porous inorganic filler, but contained only (g) an organic-inorganic composite filler. Evaluation of Comparative Example 9 showed that it had a high contrast ratio and was opaque. [Industrial Applicability]

[0171] The dental resin-reinforced glass ionomer cement composition of the present invention can be suitably used in dental treatments such as filling dental cavities, lining layers or relinings, bonding dental prosthetic devices such as crowns, inlays, and bridges to tooth structures, sealing pits and fissures, preventive coating of tooth surfaces, and core construction.

Claims

1. (a) an acid-reactive glass powder; (b) polyalkenoic acid; (c) water; (d) a polymerizable monomer; (e) porous inorganic filler: 1% by mass or more and 15% by mass or less; and (f) a polymerization initiator; A dental resin-reinforced glass ionomer cement composition comprising: A dental resin-reinforced glass ionomer cement composition characterized in that the center of the (e) porous inorganic filler is an inorganic particle composed only of silicon dioxide, or composed of silicon dioxide and an oxide containing one or more metal elements.

2. The porous inorganic filler (e) has a 50% particle diameter (D50) of 0.1 μm or more and 10 μm or less, a pore volume of 0.01 cc / g or more and 1.00 cc / g or less, and a specific surface area of ​​5 m ２ / g or more 500m ２ 2. The dental resin-reinforced glass ionomer cement composition according to claim 1, wherein the viscosity of the resin-reinforced glass ionomer cement composition is in the range of 0.1 to 1.0 g / g or less.

3. 3. The dental resin-reinforced glass ionomer cement composition according to claim 1, further comprising (g) an organic-inorganic composite filler, wherein the organic-inorganic composite filler has a 50% particle size (D50) in the range of 1 μm or more and 50 μm or less, and contains 10% by mass or more and 85% by mass or less of an inorganic filler having a 50% particle size (D50) of 0.005 μm or more and 3 μm or less.

4. The total content of the (e) porous inorganic filler and the (g) organic-inorganic composite filler is 2% by mass or more and 20% by mass or less with respect to the entire composition, and 4. The dental resin-reinforced glass ionomer cement composition according to claim 3, wherein the mass ratio of the content of the (e) porous inorganic filler to the content of the (g) organic-inorganic composite filler [(g) organic-inorganic composite filler / (e) porous inorganic filler] is 0.5 or more and 2.5 or less.

5. the (a) acid-reactive glass powder is 30% by mass or more and 80% by mass or less; (b) the polyalkenoic acid is 0.5% by mass or more and 17% by mass or less; (c) Water 0.5% by mass or more and 27% by mass or less, and the (d) polymerizable monomer is 2% by mass or more and 48% by mass or less; The dental resin-reinforced glass ionomer cement composition according to claim 1 or 2, comprising:

6. the (a) acid-reactive glass powder is 30% by mass or more and 80% by mass or less; (b) the polyalkenoic acid is 0.5% by mass or more and 17% by mass or less; (c) Water 0.5% by mass or more and 27% by mass or less, and the (d) polymerizable monomer is 2% by mass or more and 48% by mass or less; The dental resin-reinforced glass ionomer cement composition of claim 3, comprising:

7. the (a) acid-reactive glass powder is 30% by mass or more and 80% by mass or less; (b) the polyalkenoic acid is 0.5% by mass or more and 17% by mass or less; (c) Water 0.5% by mass or more and 27% by mass or less, and the (d) polymerizable monomer is 2% by mass or more and 48% by mass or less; The dental resin-reinforced glass ionomer cement composition of claim 4, comprising:

8. 3. The dental resin-reinforced glass ionomer cement composition according to claim 1, wherein the time required for starting shaping in the dental resin-reinforced glass ionomer cement composition is 40 seconds or less.

9. 4. The dental resin-reinforced glass ionomer cement composition according to claim 3, wherein the time required for starting shaping in the dental resin-reinforced glass ionomer cement composition is 40 seconds or less.

10. 5. The dental resin-reinforced glass ionomer cement composition according to claim 4, wherein the time required for starting shaping in the dental resin-reinforced glass ionomer cement composition is 40 seconds or less.

11. 6. The dental resin-reinforced glass ionomer cement composition according to claim 5, wherein the time required for starting shaping in the dental resin-reinforced glass ionomer cement composition is 40 seconds or less.

12. 7. The dental resin-reinforced glass ionomer cement composition according to claim 6, wherein the time required for starting shaping in the dental resin-reinforced glass ionomer cement composition is 40 seconds or less.

13. 8. The dental resin-reinforced glass ionomer cement composition according to claim 7, wherein the time required for starting shaping in the dental resin-reinforced glass ionomer cement composition is 40 seconds or less.

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