dental cement

Abstract

The present invention provides a dental cement which has excellent handleability, regarding kneading, filling, etc., that is less affected by the powder / liquid ratio than conventional dental portland cement and which can give cured objects having excellent compression strength. The present invention relates to a dental cement which comprises a powder component and a liquid component, wherein the powder component comprises a portland cement powder (A), the liquid component comprises water (C), and the powder component and / or the liquid component includes a cationic surfactant (B). The liquid component preferably includes the cationic surfactant (B).

Description

[Technical Field]

[0001] The present invention relates to a dental cement, and more particularly to a novel dental cement that can be suitably used for applications such as root canal filling and direct pulp capping of teeth. [Background technology]

[0002] In recent years, in the field of dentistry, dental Portland cement called MTA (Mineral Trioxide Aggregate) has been used as a dental composition having hard tissue inducing ability to treat diseases of the dental pulp or apical periodontal tissue.

[0003] MTA is made by micronizing Portland cement, a mortar material for concrete used in civil engineering and construction, for dental use, and adding radiopaque inorganic substances such as bismuth oxide, which hardens through a hydration reaction when mixed with water. This hardened material has excellent biocompatibility and hard tissue induction ability, leading to treatment involving the formation of new hard tissue in the dental pulp and root and periodontal tissues, and is therefore used in clinical applications such as direct pulp capping, pulp resection, apexification, retrograde root canal filling, and sealing of perforations.

[0004] MTA generally consists of a powder component and a liquid component, which are mixed and kneaded together to harden into a hardened cement product.

[0005] The clinical procedure for using MTA, for example in cases of exposed pulp teeth, involves applying it to the exposed pulp area and then forming a superstructure such as a temporary filling or prosthesis on top of it. However, since MTA hardens through a hydration reaction, the reaction rate is slow and it takes several days for it to fully harden. As a result, there are problems such as its low strength immediately after application and its tendency to be highly soluble.

[0006] Furthermore, when using MTA, it is necessary to prepare it by kneading the powder component and liquid component of MTA, which makes it difficult to knead and to make a uniform paste. If the powder-liquid ratio (the mixing ratio of the powder component to the liquid component) is reduced to improve kneadability, the kneaded paste tends to drip, making filling and other operations difficult, and the hardening reaction slows down, further reducing the strength of the hardened product.

[0007] Therefore, a method has been proposed to solve problems such as reaction rate, strength immediately after application, and solubility by using MTA as a polymer wet structure (Patent Document 1). Also, a composition has been disclosed that contains MTA, a polymerizable monomer, a filler, and a polymerization initiator, and that imparts operability, mechanical strength, and adhesiveness and sealing properties (Patent Document 2). Also, a composition has been disclosed in which operability and physical properties have been improved by mixing MTA with a hydrogel former (Patent Document 3). [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Special Publication No. 2007-528398 [Patent Document 2] Japanese Patent Application Laid-Open No. 2012-20983 [Patent Document 3] Japanese Patent Application Laid-Open No. 2013-151527 Summary of the Invention [Problem to be solved by the invention]

[0009] However, the compositions disclosed in Patent Documents 1 to 3 all contain polymers in the cured product obtained by curing, which may affect the excellent biocompatibility and hard tissue inducibility inherent to MTA.

[0010] In view of the above problems, an object of the present invention is to provide a dental cement that is less susceptible to influences on operability such as kneading ability and filling depending on the powder-liquid ratio, has excellent operability, and can give a hardened product with excellent compressive strength. [Means for solving the problem]

[0011] As a result of intensive research to solve the above-mentioned problems, the present inventors have found that mixing and kneading Portland cement powder, a cationic surfactant, and water makes mixing easier than simply mixing Portland cement powder and water, and that a kneaded product with excellent properties can be obtained. Furthermore, they have found that even if the amount of liquid component mixed during kneading is small compared to the powder component containing Portland cement powder (high powder-liquid ratio), it is unlikely to cause problems when handling the paste of the kneaded product, and furthermore, it is possible to obtain a hardened product with excellent properties. After further research, they have completed the present invention.

[0012] That is, the present invention includes the following inventions. [1] A powder component and a liquid component are provided, The powder component includes Portland cement powder (A), The liquid component contains water (C), A dental cement, wherein at least one of the powder component and the liquid component contains a cationic surfactant (B). [2] The dental cement according to [1], wherein the liquid component contains a cationic surfactant (B). [3] The dental cement according to [1] or [2], wherein the proportion of the cationic surfactant (B) in the liquid component is 0.05 to 25% by mass. [4] The dental cement according to any one of [1] to [3], wherein the powder component contains a cationic surfactant (B). [5] The dental cement according to [4], wherein the content of the cationic surfactant (B) in the powder component is 0.1 to 5% by mass. [6] The dental cement according to any one of [1] to [5], wherein the cationic surfactant (B) is a cationic surfactant represented by the following general formula (I): [ka] [In the formula, R is a hydrogen atom or a (meth)acryloyloxy group, n is an integer of 10 to 20, and X is a chlorine atom or a bromine atom] [7] The dental cement according to any one of [1] to [6], wherein the Portland cement powder (A) contains at least one inorganic component selected from the group consisting of calcium oxide, silicon dioxide, and calcium sulfate. [8] The dental cement according to any one of [1] to [7], wherein the cationic surfactant (B) is at least one selected from the group consisting of cetylpyridinium chloride, 12-methacryloyloxydodecylpyridinium bromide, hexadecyltrimethylammonium chloride, and octadecyltrimethylammonium chloride. [Effects of the Invention]

[0013] According to the present invention, a dental cement is provided which is less susceptible to influences on the operability of mixing and filling, etc. depending on the powder-liquid ratio, and which is excellent in operability and can give a hardened product with excellent compressive strength.Furthermore, according to the present invention, the dental cement has excellent sustained release properties of calcium ions. DETAILED DESCRIPTION OF THE INVENTION

[0014] The dental cement of the present invention comprises a powder component and a liquid component, wherein the powder component contains Portland cement powder (A), the liquid component contains water (C), and at least one of the powder component and the liquid component contains a cationic surfactant (B). In this specification, "(meth)acryloyloxy" is a general term for methacryloyloxy and acryloyloxy. In this specification, the upper and lower limits of the numerical ranges (contents of each component, values ​​calculated from each component, physical properties, etc.) can be appropriately combined.

[0015] When Portland cement powder is kneaded with water, a hydration reaction begins and the hardening reaction progresses. Generally, Portland cement powder and water do not mix well, so the water and powder do not easily combine, resulting in a crumbly texture and difficulty in kneading them into a paste. Even if it is possible to knead it into a paste, upon microscopic observation, there are Portland cement powder agglomerates that have not been mixed with water, and these agglomerates remain unreacted and scattered throughout the hardened product. The presence of unreacted agglomerates scattered throughout the hardened product means that the hardened product will have a low strength compared to an ideal product that has been thoroughly kneaded until there are no agglomerates and the hydration reaction has occurred throughout the Portland cement powder.

[0016] In the present invention, the surface-active function of the cationic surfactant enhances the compatibility between Portland cement powder and water, and kneading breaks down Portland cement powder agglomerates, allowing the hydration reaction to occur throughout the Portland cement powder. In other words, the hydration reaction is brought about down to every single particle of Portland cement powder. Furthermore, the enhanced compatibility between Portland cement powder and water results in a smooth mixing feel and improved mixing operability. As a result, even if the ratio of powder components including Portland cement powder is increased during kneading, this does not interfere with the handling of the paste of the mixed mixture, further increasing the strength of the set product.

[0017] The reason why the cationic surfactant (B) is selected as the surfactant of the present invention is that Portland cement powder is basic, and furthermore, the hydration reaction environment is strongly basic because it releases cationic metal ions during the hydration reaction. Even in such an environment, the cationic surfactant can provide effective surface activity.

[0018] On the other hand, anionic surfactants not only fail to function as surfactants because they adsorb to Portland cement powder or are neutralized by metal ions, but also interfere with the hydration reaction due to their adsorption to Portland cement powder.Nonionic surfactants also do not function adequately as surfactants in the strongly basic hydration reaction environment, and instead act as foreign substances that inhibit the hydration reaction between Portland cement powder and water.

[0019] The dental cement of the present invention comprises a powder component and a liquid component. By providing the cement in this divided package, mixing is easier than simply mixing Portland cement powder with water, and a mixed product with excellent properties can be obtained. Furthermore, even if the amount of liquid component mixed during mixing is small (high powder-liquid ratio), it is less likely to cause problems when handling the mixed product as a paste, and a hardened product with even better properties can be obtained.

[0020] As the Portland cement powder (A), any conventional Portland cement (general-purpose Portland cement) generally used for civil engineering and construction purposes can be used without particular limitation, but it is preferable to use Portland cement that has been appropriately refined and / or blended with additives for dental use.

[0021] Examples of the Portland cement used in the present invention include powders of ordinary Portland cement, high-early-strength Portland cement, ultra-high-early-strength Portland cement, white Portland cement, sulfate-resistant Portland cement, moderate-heat Portland cement, and low-heat Portland cement, as specified in JIS R 5210:2019.

[0022] Of these, it is particularly preferable to use white Portland cement, as it has a white color that is close to the color of tooth structure.

[0023] Portland cement powder (A) having the following composition is particularly preferable because it allows the kneaded product to harden stably and to obtain an appropriate strength when used under moist conditions such as root canal filling and pulp capping. Note that Portland cement powder (A) may contain other components such as magnesium oxide and sodium carbonate.

[0024] The Portland cement powder (A) used in this invention is a cement whose main components are tricalcium silicate (alite, 3CaO·SiO2), dicalcium silicate (belite, 2CaO·SiO2), calcium aluminate (aluminate, 3CaO·Al2O3), and calcium aluminoferrite (ferrite, 4CaO·Al2O3·Fe2O3). It is primarily composed of calcium oxide and silicon oxide, with small amounts of calcium sulfate and aluminum oxide, and, optionally, oxides or salts of transition metals such as iron, other alkali metal elements, and alkaline earth elements, preferably in the form of a solid solution. The main components are calcium oxide (CaO), silicon dioxide (SiO2), aluminum oxide (Al2O3), and iron oxide (Fe2O3). Although not particularly limited, the general composition of commonly known Portland cement is such that, calculated as the oxide of each element, the CaO content is preferably 4 to 85 mass%, more preferably 40 to 85 mass%, even more preferably 55 to 75 mass%, and particularly preferably 60 to 70 mass%. The SiO2 content is preferably 10 to 95 mass%, more preferably 10 to 50 mass%, even more preferably 15 to 40 mass%, and particularly preferably 18 to 32 mass%. The Al2O3 content is preferably 0 to 17 mass%, more preferably 0 to 15 mass%, even more preferably 1.5 to 8 mass%, and particularly preferably 2.5 to 6 mass%. The Fe2O3 content is preferably 0 to 4.7 mass%, more preferably 0 to 4.5 mass%, even more preferably 0.2 to 2 mass%, and particularly preferably 0.5 to 1 mass%. The content of MgO is preferably 0.02 to 5 mass%, more preferably 0.2 to 5 mass%, further preferably 0.7 to 3 mass%, and particularly preferably 0.8 to 2 mass%, with the remainder being transition metals other than those mentioned above (for example, vanadium and copper), other alkali metal elements, and the like.

[0025] Furthermore, as a silicon component, amorphous silicon dioxide such as fumed silica, nano-sized silicon dioxide, or spherical silicon dioxide may be contained as a Portland cement component. However, in the Portland cement powder (A), these components rarely exist as powders or particles alone, but exist as a solid solution in which multiple components are mixed.

[0026] In addition to the powder mainly composed of a metal oxide powder such as calcium oxide, silicon dioxide, aluminum oxide, or iron oxide, and calcium sulfate, other powder components may include inorganic substances such as metal salt powders such as calcium carbonate, and glass fillers such as silica glass and aluminum-containing glass.

[0027] The average particle size of the Portland cement powder (A) is preferably 100 μm or less, more preferably in the range of 1 to 50 μm, and even more preferably in the range of 5 to 30 μm.

[0028] The average particle size of the Portland cement powder (A) refers to the particle size at 50% cumulative volume in the particle size distribution measured by a laser diffraction / scattering method, i.e., D50 (median diameter). Specifically, it can be measured on a volume basis using a laser diffraction particle size distribution analyzer (such as the "SALD-2300" manufactured by Shimadzu Corporation) using ethanol as a dispersion medium.

[0029] The Portland cement powder (A) may be in the form of, for example, powder or granules.

[0030] As the Portland cement powder (A), for example, commercially available products such as "Proroot MTA" (manufactured by Dentsply Sankin Co., Ltd.) and "White Cement" (manufactured by Taiheiyo Cement Corporation) can also be used.

[0031] The cationic surfactant (B) used in the present invention increases the compressive strength of the hardened product of the dental cement containing the Portland cement powder (A) after hardening. Furthermore, the cationic surfactant (B) facilitates mixing compared to simply mixing Portland cement powder with water, thereby enabling a mixed product with excellent properties to be obtained. Increasing the proportion of powder during mixing does not cause any problems when handling the mixed paste, resulting in a hardened product with even better properties.

[0032] As the cationic surfactant (B) used in the present invention, monoalkyltrimethylammonium salts, dialkyldimethylammonium salts, trialkylmonomethylammonium salts, tetraalkylammonium salts, monoalkyldimethylbenzylammonium salts, polyoxyethylenealkylmethylammonium salts, compounds represented by the following general formula (I), and the like can be preferably used.

[0033] [ka] [In the formula, R is a hydrogen atom or a (meth)acryloyloxy group, n is an integer of 10 to 20, and X is a chlorine atom or a bromine atom]

[0034] Specific examples of the cationic surfactant (B) include cetylpyridinium chloride (CPC), 12-methacryloyloxydodecylpyridinium bromide (MDPB), hexadecyltrimethylammonium chloride (CTC), octadecyltrimethylammonium chloride (ODTC), etc. The cationic surfactant (B) can be used alone or in combination of two or more.

[0035] Of these cationic surfactants (B), the cationic surfactants represented by the above general formula (I) are preferably used in terms of the compatibility of the powder component with the liquid component and the strength of the cured product.

[0036] As the compound represented by the above general formula (I), alkylpyridinium chloride salts, methacryloyloxyalkylpyridinium chloride salts, methacryloyloxyalkylpyridinium bromide salts, etc. are particularly preferred, and more specifically, cetylpyridinium chloride and 12-methacryloyloxydodecylpyridinium bromide are more preferred.

[0037] In the present invention, the reason why the compound represented by the above general formula (I) is preferred among the cationic surfactants (B) is not clear in detail, but it is thought that the presence of a pyridinium skeleton affects the action of the cationic surfactant in manifesting the effects of the present invention.

[0038] In the dental cement according to the present invention, the content of the cationic surfactant (B) in the dental cement is preferably 0.01 to 6 mass %, more preferably 0.05 to 5.5 mass %, and even more preferably 0.1 to 5 mass %.

[0039] In the dental cement according to the present invention, at least one of the powder component and the liquid component contains a cationic surfactant (B).

[0040] In the dental cement according to the present invention, when the cationic surfactant (B) is contained in the liquid component, the proportion of the cationic surfactant (B) in the liquid component is preferably 0.05 to 25 mass%, more preferably 0.1 to 15 mass%, even more preferably 0.2 to 10 mass%, and particularly preferably 0.2 to 6 mass%. Having the proportion of the cationic surfactant (B) in the liquid component of 0.05 mass% or more can improve operability and increase the strength of the cured product. On the other hand, having the proportion of the cationic surfactant (B) of 25 mass% or less can increase the strength of the cured product.

[0041] The dental cement according to the present invention may contain a cationic surfactant (B) in the powder component. The content of the cationic surfactant (B) in the powder component is preferably 0.1 to 5% by mass, more preferably 0.1 to 4.5% by mass. When the content is 0.1% by mass or more, the effect of improving operability and increasing the strength of the cured product can be achieved. On the other hand, when the content is 5% by mass or less, the effect of increasing the strength of the cured product can be achieved.

[0042] The water (C) used in the present invention is a component that undergoes a hydration reaction when mixed with the powder component to promote curing, and also functions as a solvent to dissolve the cationic surfactant (B). It is preferable to use water (C) that is substantially free of impurities that adversely affect the curing reaction, and it is more preferable to use distilled water or ion-exchanged water.

[0043] In the dental cement of the present invention, the ratio of the powder component to the liquid component is not particularly limited, but in order to further enhance the effects of the present invention, the liquid component is preferably 10 to 70 parts by mass, more preferably 15 to 70 parts by mass, and even more preferably 15 to 50 parts by mass, per 100 parts by mass of the powder component. Even when the dental cement of the present invention contains a large amount of powder component, it has excellent kneadability and can give a cured product with excellent compressive strength.

[0044] The powder component of the dental cement according to the present invention may contain an X-ray contrast material to impart X-ray contrast properties.

[0045] Examples of X-ray contrast materials that can be used include known powders of bismuth oxide, barium sulfate, tantalum oxide, cerium oxide, tin oxide, zirconium oxide, zinc oxide, ytterbium oxide, and ytterbium fluoride, as well as X-ray opaque glass powders containing barium, tantalum, lanthanum, and strontium, and these can be used alone or in combination.

[0046] The content of the X-ray contrast material may be any amount that does not impair the effects of the present invention, and is preferably, for example, 0.1 to 50% by mass in the powder component. Note that if it is less than 0.1% by mass, the X-ray contrast properties of the cured product obtained by kneading with the liquid component are likely to be insufficient, and if it exceeds 50% by mass, the strength of the cured product may decrease.

[0047] Furthermore, the dental cement of the present invention can be blended with other additives such as fillers, colorants, stabilizers, etc., as long as they do not affect the physical properties or operability. The additives may be used alone or in combination of two or more.

[0048] The content of the additive in the dental cement is preferably less than 10% by mass, more preferably 0 to 5% by mass, and even more preferably 0 to 3% by mass.

[0049] The compressive strength of the cured product of the dental cement of the present invention is preferably more than 40 MPa, more preferably 45 MPa or more, and even more preferably 50 MPa or more. The method for measuring the compressive strength of the cured product is as described in the Examples below. [Example]

[0050] The dental cement according to the present invention will be specifically described below using examples, but the dental cement according to the present invention is not limited to the following examples.

[0051] [Explanation of abbreviations] The abbreviations used in the following examples have the following meanings. Portland cement powder (A) PO1: Dental Portland cement powder (product name "Proroot MTA": powder manufactured by Dentsply Sankin Co., Ltd.: calcium oxide, silicon dioxide, bismuth oxide, aluminum oxide, etc.) PO2: White Portland cement powder (product name: White Cement, manufactured by Taiheiyo Cement Corporation)

[0052] Cationic surfactant (B) CPC: cetylpyridinium chloride MDPB: 12-methacryloyloxydodecylpyridinium bromide CTC: hexadecyltrimethylammonium chloride ODTC: Octadecyltrimethylammonium chloride Surfactants other than cationic surfactants (B) DBS: sodium dodecylbenzenesulfonate MDP: 10-methacryloyloxydecyl dihydrogen phosphate

[0053] [Mixability] The dental cements of the examples and comparative examples listed in Tables 1, 2 and 3 were mixed with a spatula for 30 seconds, and the appearance of the mixed product was checked by touch and visual inspection, and the mixing properties (ease of mixing) were evaluated as follows. ◎: The powder and liquid are highly compatible and easily form a uniform paste ○: Can be kneaded to form a uniform paste △: Mixing is possible, but the mixture does not come together uniformly ×: The powder and liquid do not blend well together, and / or the amount of liquid is too small to mix.

[0054] [Ease of use] The dental cements of the Examples and Comparative Examples listed in Tables 1, 2, and 3 that were able to be mixed in the "mixability" test were mixed in the same manner as in the "mixability" test, and the mixed product was loaded into a metal mold with an inner diameter of 4 mm and a height of 6 mm using a spatula. The state of loading was confirmed by touch and visual inspection, and the operability was evaluated as follows. ○: The kneaded product has a moderate viscosity and a sense of cohesion, making it easy to fill. △: It was possible to fill it, but the viscosity was a little difficult. ×: The mixture feels crumbly and lacks cohesion, making it difficult to fill.

[0055] [Compression strength] The test was carried out in accordance with ISO 9917-1:2003 (Dental - Water-based Cements Part 1: Powder / Liquid (Type) Acid-Base (Reactive) Cements). The dental cements of the Examples and Comparative Examples listed in Tables 1, 2, and 3 were mixed with a spatula for 30 seconds, and the mixed material was loaded into a metal mold with an inner diameter of 4 mm and a height of 6 mm. After mixing, the material was left to stand in a thermo-hygrostat at 37°C and a relative humidity of 100% for 1 hour. The cured material was then removed from the mold to obtain a cylindrical test piece. The test piece was immersed in distilled water at 37°C for 24 hours, and then the compressive strength was measured at a crosshead speed of 1.0 mm / min using a universal testing machine (Shimadzu Corporation, product name "Autograph AG-I 100kN")

[0056] [Examples 1 to 21 and Comparative Examples 1 to 4] Hardened dental cements were prepared using the formulations shown in Tables 1, 2, and 3, and the kneading properties, handling properties, and compressive strength were measured and evaluated. The results are shown in Tables 1, 2, and 3.

[0057] [Table 1]

[0058] [Table 2]

[0059] [Table 3]

[0060] The results in Tables 1, 2, and 3 show that the compressive strength and operability of the hardened product of the dental cement of the present invention were superior to those of the hardened products of the dental cements of the comparative examples. It was found that there is a correlation between kneading ability and operability, and that there is also a correlation with high compressive strength. It is presumed that when the liquid component and dental cement are well compatible, kneading ability is improved, the dental cement and liquid component are well kneaded, and the hardening reaction proceeds uniformly without leaving any clumps of dental cement, resulting in high compressive strength.

[0061] [Example 22] The amount of calcium ions released from the hardened dental cement of Example 2 listed in Table 1 was measured. The amount of calcium ions released was measured by measuring calcium ions eluted from the hardened dental cement immersed in water using an ion electrode method. The dental cement of Example 2 listed in Table 1 was mixed with a spatula for 30 seconds, and the mixture was loaded into a mold with an inner diameter of 15 mm and a height of 1 mm. The mold was left to stand in a thermo-hygrostat at 37°C and a relative humidity of 100% for 1 hour after mixing was completed. The hardened product was then removed from the mold to obtain a disk-shaped test piece. The mass of the test piece was measured, immersed in 5 ml of ion-exchanged water, and stored in a 37°C incubator for 1 week. The test piece was removed from the ion-exchanged water, and 10 μl of 5 mol / l hydrochloric acid, 15 ml of trishydroxyaminomethane buffer solution, and 1 ml of potassium chloride solution were added. The Ca ion concentration was measured using a compact water quality meter (LAQUAtwin-Ca-11, manufactured by Horiba Advanced Techno Co., Ltd.). The Ca ion release amount was found to be 15,600 μg / g.

[0062] Comparative Example 5 Dental resin cements containing Portland cement powder having the components shown in Table 4 were prepared.

[0063] [Table 4]

[0064] The amount of calcium ions released from the hardened dental cement was measured using the same procedure and method as in Example 22, except that the dental resin cement listed in Table 4 was used instead of the dental cement of Example 2. The result was 5800 μg / g.

[0065] In this way, when Portland cement powder is blended with dental resin cement containing monofunctional monomers such as methyl methacrylate, the Ca ion elution effect of Portland cement is not obtained, and the amount of sustained release of Ca ions is significantly suppressed.

[0066] The evaluation results showed that dental cement containing Portland cement powder (A), cationic surfactant (B), and water (C) does not inhibit the release of calcium ions, and the powder-liquid ratio is less likely to affect the operability of mixing and filling, making it possible to obtain a hardened product with excellent operability and compressive strength. [Industrial Applicability]

[0067] The dental cement of the present invention can be suitably used as an MTA cement, and can be used for root canal filling, direct pulp capping, and other treatments for diseases of the dental pulp or apical periodontal tissues.

Claims

1. 1. A dental cement comprising a powder component and a liquid component, The powder component includes Portland cement powder (A), The liquid component contains water (C), At least one of the powder component and the liquid component contains a cationic surfactant (B), A dental cement, wherein the proportion of the cationic surfactant (B) in the dental cement is 0.05 to 5.5% by mass.

2. The dental cement of claim 1 , wherein the liquid component comprises a cationic surfactant (B).

3. 3. The dental cement according to claim 1, wherein the content of the cationic surfactant (B) in the liquid component is 3 to 25% by mass.

4. The dental cement according to any one of claims 1 to 3, wherein the powder component comprises a cationic surfactant (B).

5. 5. The dental cement according to claim 4, wherein the content of the cationic surfactant (B) in the powder component is 0.1 to 5% by mass.

6. 6. The dental cement according to claim 1, wherein the cationic surfactant (B) is a cationic surfactant represented by the following general formula (I): 【Chemical 1】 [wherein R is a hydrogen atom or a (meth)acryloyloxy group, n is an integer of 10 to 20, and X is a chlorine atom or a bromine atom]

7. 7. The dental cement according to claim 1, wherein the Portland cement powder (A) contains at least one inorganic component selected from the group consisting of calcium oxide, silicon dioxide, and calcium sulfate.

8. The dental cement according to any one of claims 1 to 7, wherein the cationic surfactant (B) is at least one selected from the group consisting of cetylpyridinium chloride, 12-methacryloyloxydodecylpyridinium bromide, hexadecyltrimethylammonium chloride, and octadecyltrimethylammonium chloride.

9. A dental cement described in any one of claims 1 to 8, wherein the proportion of the cationic surfactant (B) in the dental cement is 0.5 to 5.5 mass%.

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