JP2012188378A - Dental adhesive composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To develop a dental adhesive composition in which the gelling is hardly caused even if a long period of time is kept by one liquid state, and the excellent bond strength can be excellently maintained and exerted in the dental adhesive composition including an acid group containing polymerizable monomer, a polyvalent metal ion, and water.SOLUTION: The dental adhesive composition includes: (A) an acid group containing polymerizable monomer, suitably a phosphinico oxy group and phosphonooxy group containing polymerizable monomer; (B) a polyvalent metal ion, suitably a titanium ion; and (C) water containing at least 10% by mass of heavy water.

Description

  The present invention relates to a dental adhesive composition used for bonding a dental restoration made of a metal, an organic polymer, ceramics, or a composite material thereof, and a tooth in the dental field.

  If the tooth is damaged by caries or the like, if it is a relatively small cavity in the first mid-stage, it is directly restored by a composite resin in terms of aesthetics, simplicity of operation, and speed. On the other hand, in the case of a relatively large cavity, restoration using a prosthesis made of metal, ceramics, or dental resin is performed.

Dental restorations such as composite resins and prosthetics have almost no adhesiveness to the tooth, and thus are adhered to the tooth using an adhesive composed of a polymerizable monomer composition. The polymerizable monomer used for the adhesive is usually composed mainly of a methacrylate-based polymerizable monomer, and it cannot be said that the adhesive force to the tooth is sufficient. For example, in the case of adhesion of a composite resin, it often does not reach an adhesive strength that can overcome the internal stress generated upon curing, that is, the tensile stress generated at the interface between the tooth and the composite resin. Furthermore, the adhesive strength that can withstand the force applied by occlusion is often not reached. Therefore, for the purpose of improving the adhesive strength, the following pretreatment is performed on the tooth surface before using the adhesive. That is,
1) Application of a pretreatment material for etching hard teeth (mainly enamel mainly composed of hydroxyapatite);
2) In order to promote the penetration of the adhesive into the tooth, a pretreatment material called a primer is applied.

  Under such circumstances, a dental adhesive containing a polymerizable monomer having a high adhesiveness to a tooth has been developed for the purpose of reducing the complexity of the above-described operation. For example, as at least a part of the polymerizable monomer component, a polymerizable monomer having an acidic group such as a phosphate group or a carboxylic acid group having a high affinity for a tooth (hydroxyapatite or collagen) ( Hereinafter, those containing an acidic group-containing polymerizable monomer have been proposed (Patent Document 1 and Patent Document 2).

  In addition, there is a report of improving the adhesive strength by using a phosphoric acid monoester monomer as an acidic group-containing polymerizable monomer and using it in the form of a metal salt with calcium or the like (Patent Document) 3). In addition, it is also known that a polyvalent metal ion-eluting filler is added to a pretreatment material or an adhesive containing an acidic group-containing polymerizable monomer and water to greatly increase curability (patent) References 4-7). Here, the polyvalent metal ion-eluting filler corresponds to a filler that elutes polyvalent metal ions in an acid aqueous solution such as fluoroaluminosilicate glass. Further, as the eluted polyvalent metal ions, alkaline earth metals, aluminum and the like are common.

  In the adhesive containing such a polyvalent metal ion-eluting filler, the adhesive strength is improved by the polymerization of the polymerizable monomer containing the acidic group-containing polymerizable monomer when the adhesive is cured. It is thought that the polyvalent metal ion eluted from the polyvalent metal ion-eluting filler forms a salt with the acidic group of the acidic group-containing polymerizable monomer, thereby causing ionic crosslinking.

JP-A-52-113089 JP 58-21687 Japanese Patent Laid-Open No. 53-113843 JP-A-9-263604 Japanese Patent Laid-Open No. 10-236912 JP 2001-72523 A JP 2000-86421 A

  Adhesives composed of acidic group-containing polymerizable monomers, polyvalent metal ions, and water proposed in Patent Documents 4 to 7 and the like are, as described above, acidic group-containing polymerizable monomers and polyvalent metal ions. An ionic crosslink is formed between the two, and thereby a high adhesive strength can be obtained, which is very useful. However, if it is stored for a long time in a state where the acidic group-containing polymerizable monomer, polyvalent metal ion and water coexist (one liquid state), an ionic cross-link is gradually formed and gels before use. The phenomenon occurred. Moreover, even when the adhesive material which has started to be gelled in this way, even when the liquid portion is subjected to adhesion of the dental restoration to the dentin, the adhesive strength is no longer greatly reduced. That is, this adhesive has a big problem in storage stability, and further improvement has been demanded.

  As a result of intensive studies to overcome the above technical problems, the present inventors have found that using water containing a large amount of heavy water is very effective for suppressing the occurrence of gelation. The headline and the present invention have been completed.

That is, the present invention
(A) an acidic group-containing polymerizable monomer,
A dental adhesive composition comprising (B) polyvalent metal ions and (C) water containing 10% by mass or more of heavy water.

  The dental adhesive composition of the present invention has better gelation that progresses over time during storage compared to conventional adhesives comprising an acidic group-containing polymerizable monomer, a polyvalent metal ion, and water. It has an effect that can be suppressed. Therefore, it can be stored for a long time in one liquid state while maintaining its excellent adhesion performance, and its practical value can be greatly enhanced.

  Hereinafter, each of the water which comprises the dental adhesive composition of this invention which contains 10 mass% or more of (A) acidic group containing polymerizable monomer, (B) polyvalent metal ion, and (C) heavy water. The components will be described sequentially.

<(A) Acidic group-containing polymerizable monomer>
In the present invention, the acidic group-containing polymerizable monomer is not particularly limited as long as it is a polymerizable monomer having at least one polymerizable unsaturated group and at least one acidic group in one molecule. Compounds can be used. Here, examples of the polymerizable unsaturated group include (meth) acryloyl group, (meth) acryloyloxy group, (meth) acryloylamino group, (meth) acryloylthio group, vinyl group, allyl group, styryl group and the like. The Among these, a (meth) acryloyl group, a (meth) acryloyloxy group, and a (meth) acryloylamino group are preferable from the viewpoint of curing rate.

The acidic group is a phosphinico group {= P (═O) OH}, a phosphono group {—P (═O) (OH) ₂ }, a phosphinicooxy group {(—O—) ₂ P (═O )}}, Phosphonooxy group {—O—P (═O) (OH) ₂ }, carboxyl group {—C (═O) OH}, sulfo group (—SO ₃ H) and the like. Further, not only these free acidic groups, but also an acid anhydride structure (for example, —C (═O) —O—C (═O) —) in which two of the acidic groups are dehydrated and condensed, or an acidic group Any acid halide group in which OH is substituted with a halogen (for example, —C (═O) Cl) or the like can be used as long as the group exhibits acidity as an aqueous solution or aqueous suspension.

  Specific examples of the acidic group-containing polymerizable monomer include (meth) acrylic acid, N- (meth) acryloylglycine, N- (meth) acryloylaspartic acid, N- (meth) acryloyl-5-aminosalicylic acid, 2- (meth) acryloyloxyethyl hydrogen succinate, 2- (meth) acryloyloxyethyl hydrogen phthalate, 2- (meth) acryloyloxyethyl hydrogen maleate, 6- (meth) acryloyloxyethyl naphthalene-1,2 , 6-tricarboxylic acid, O- (meth) acryloyl tyrosine, N- (meth) acryloyl tyrosine, N- (meth) acryloylphenylalanine, N- (meth) acryloyl-p-aminobenzoic acid, N- (meth) acryloyl- O-aminobenzoic acid, p-vinylbenzoic acid 2- (meth) acryloyloxybenzoic acid, 3- (meth) acryloyloxybenzoic acid, 4- (meth) acryloyloxybenzoic acid, N- (meth) acryloyl-5-aminosalicylic acid, N- (meth) acryloyl- Polymerizable monomer having one carboxyl group in the molecule such as 4-aminosalicylic acid; 11- (meth) acryloyloxyundecane-1,1-dicarboxylic acid, 10- (meth) acryloyloxydecane-1,1 -Dicarboxylic acid, 12- (meth) acryloyl oxide decane-1,1-dicarboxylic acid, 6- (meth) acryloyloxyhexane-1,1-dicarboxylic acid, 2- (meth) acryloyloxyethyl-3'-methacryloyloxy -2 '-(3,4-dicarboxybenzoyloxy) propyl succinate, 1,4- (2- (meth) acryloyloxyethyl) pyromellitate, N, O-di (meth) acryloyltyrosine, 4- (2- (meth) acryloyloxyethyl) trimellitate anhydride, 4- (2- (meth) (Acryloyloxyethyl) trimellitate, 4- (meth) acryloyloxyethyl trimellitate, 4- (meth) acryloyloxybutyl trimellitate, 4- (meth) acryloyloxyhexyl trimellitate, 4- (meth) acryloyloxydecyl Trimellitate, 4-acryloyloxybutyl trimellitate, 6- (meth) acryloyloxyethylnaphthalene-1,2,6-tricarboxylic acid anhydride, 6- (meth) acryloyloxyethylnaphthalene-2,3,6- Tricarboxylic anhydride, 4- (meth) ac Royloxyethylcarbonylpropionoyl-1,8-naphthalic anhydride, 4- (meth) acryloyloxyethylnaphthalene-1,8-tricarboxylic acid anhydride and the like, a plurality of carboxyl groups or acid anhydride groups thereof 2- (meth) acryloyloxyethyl dihydrogen phosphate, bis (2- (meth) acryloyloxyethyl) hydrogen phosphate, 2- (meth) acryloyloxyethyl phenyl hydrogen Molecules such as phosphate, 10- (meth) acryloyloxydecyl dihydrogen phosphate, 6- (meth) acryloyloxyhexyl dihydrogen phosphate, 2- (meth) acryloyloxyethyl 2-bromoethyl hydrogen phosphate A polymerizable monomer having a phosphinicooxy group or a phosphonooxy group in the polymer; a polymerizable monomer having a phosphono group in the molecule such as vinyl phosphoric acid and p-vinylbenzenephosphoric acid; 2- (meth) acrylamide- Examples thereof include polymerizable monomers having a sulfo group in the molecule such as 2-methylpropanesulfonic acid, p-vinylbenzenesulfonic acid, and vinylsulfonic acid. In addition to these, JP-A Nos. 54-11149, 58-140046, 59-15468, 58-173175, 61-293951 are disclosed. Dental adhesives disclosed in JP-A-7-179401, JP-A-8-208760, JP-A-8-319209, JP-A-10-236912, JP-A-10-245525, etc. The acidic monomer described as a component of can also be used suitably.

  The acidic group-containing polymerizable monomer can be used alone or in admixture of two or more. Among them, those having an acid valence of 2 or more in the molecule develop an ionic bond. It is preferable because it can be formed. In the molecule, the acidic group-containing polymerizable monomer having an acid valence of 2 or more may be in a form having two or more monovalent acid groups in the molecule, or a divalent acid group. If there is only one in the molecule, this requirement is satisfied. Thus, in the molecule, when only the acidic group-containing polymerizable monomer having an acid valence of 2 or more is used, it is preferable from the viewpoint of improving the adhesive strength as described above, but the storage stability is slightly Since it tends to decrease, it is more preferable to use in combination with a polymerizable monomer having a monovalent acidic group. Among them, it is particularly preferable to use a combination of a phosphinicooxy group and a phosphonooxy group because high adhesive strength can be obtained and storage stability can be improved.

<(B) Multivalent metal ion>
In the present invention, the polyvalent metal ion means a divalent or higher-valent metal ion capable of ionic bonding with the acidic group contained in the acidic group-containing polymerizable monomer. Specific examples include divalent metal ions such as magnesium, calcium, strontium, barium, zinc, copper (II) and tin (II), and trivalent metal ions include aluminum. , Gallium, indium, scandium, yttrium, lanthanum, cerium, praseodymium, promethium, neodymium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, iron (III), actinium, and the like. Examples of tetravalent or higher metal ions include titanium ions, zirconium ions, tungsten (IV) ions, and the like. Of these, metal ions having a valence of 3 or more are preferable because of high adhesive strength. Among these, tetravalent polyvalent metal ions are particularly suitable because they can increase the crosslink density of the cured body and further improve the water resistance of the cured body, and titanium ions are most preferable. In addition, since tetravalent polyvalent metal ions (particularly titanium ions) have a strong effect of increasing the crosslink density of the cured product, the above adhesive strength is high, but the occurrence of gelation during storage is particularly severe. The decrease in the temperature is originally a system that progresses quickly. On the other hand, in the present invention, even an adhesive composition containing the tetravalent polyvalent metal ions can suppress the occurrence of such gelation to a high degree, and the effect can be particularly remarkably exhibited.

In the adhesive composition of the present invention, the content of polyvalent metal ions is not particularly limited, but the following formula (1):
R _{P +} = TV _{P +} / TV _A (1)
(In the formula, TV _{P +} is the total valence of (B) polyvalent metal ions contained in the composition, and TV _A is the (A) acidic group-containing polymerizable monomer contained in the composition. It is preferable that the total value-quantity ratio (R _{P +} ) defined by (the total value of acid groups having an acid group) is in the range of 0.1 to 1.5. When RP ₊ is smaller than 0.1, sufficient adhesion strength cannot be obtained although decalcification is performed. On the other hand, even if this ratio is larger than 1.5, the adhesiveness is not sufficient, the water resistance is lowered, and the long-term durability after bonding is lowered.

When the coexistence amount of polyvalent metal ions increases, many of the acidic groups in the phosphate group-containing polymerizable monomer component are ion-bonded and neutralized. When _{RP +} is 1 or more, the adhesive composition usually exhibits almost no acidity, and the resulting adhesive composition does not have an etching function (dental decalcification function), and the adhesive strength decreases. However, when using what forms an art complex like a titanium ion, even if RP ₊ is 1 or more, it exhibits acidity, and its adhesive strength does not decrease so much. However, even in the polyvalent metal ion forming such an art complex, if the coexistence amount is too large, a large number of titanium ions are bonded to the acidic group of the acidic group-containing polymerizable monomer, RP ₊ is preferably 1.5 or less because the ratio of ionic bonds per titanium ion is reduced (that is, titanium ions that bind all four valences are reduced) and it is difficult to obtain sufficient adhesive strength. From the viewpoint of sufficiently exerting the decalcification function of the tooth in the acidic group-containing polymerizable monomer, RP ₊ is more preferably 0.2 to 0.9, and 0.2 to 0.6. Is most preferred.

In the formula indicating the total valence quantity ratio ( _{RP +} ), the total valence quantity (TV _A ) of the acidic groups contained in the acidic group-containing polymerizable monomer contained in the adhesive composition is expressed by the following formula (1a ):
TV _A = ΣP _k × A _k (1a)
(In the formula, k is 1, 2, 3,..., N, n is the number of acidic group-containing polymerizable monomers contained in the composition, and P _k is the composition. The number of moles of the acidic group-containing polymerizable monomer contained therein, and _Ak is the valence of the acidic group of the acidic group-containing polymerizable monomer)
Is calculated by For example, in the case of a polymerizable monomer having a dialkyl phosphate group such as bis (2- (meth) acryloyloxyethyl) hydrogen phosphate, the valence of the acidic group is monovalent. Moreover, if it is a polymerizable monomer which has monoalkyl phosphate groups, such as 2- (meth) acryloyloxyethyl dihydrogen phosphate, the valence of an acidic group will be bivalent. In addition, when the acidic group-containing polymerizable monomer contained in the composition is only one kind of dialkyl phosphate polymerizable monomer, the dialkyl phosphate polymerizable monomer is expressed by the above formula. The value quantity calculated for is the total value quantity (TV _A ). On the other hand, when plural kinds of acidic group-containing polymerizable monomers including the dialkyl phosphate polymerizable monomer are contained in the composition, the valence quantity for each acidic group-containing polymerizable monomer , And the sum of these values is the total value quantity (TV _A ).

Furthermore, the total valence quantity (TV _{P +} ) of the polyvalent metal ions contained in the composition is:
TV _{P +} = ΣI _k × B _k (1b)
(Wherein k is 1, 2, 3,..., N, n is the number of types of metal ions contained in the composition, and I _k is the number of each of the various ions contained in the composition. The number of moles of valent metal ions, and B _k is the valence of each polyvalent metal ion)
Is calculated by

  The type and content of polyvalent metal ions present in the dental adhesive of the present invention can be determined by measuring using an inductively coupled plasma (ICP) emission spectrometer after removing solid components. it can. Specifically, the adhesive is diluted with a water-soluble organic solvent to a concentration of 1% by mass, and the obtained diluted solution is filtered using a syringe filter or the like to remove the solid component. Next, the ion species and ion concentration of the obtained filtrate are measured with an ICP emission spectrometer, and the polyvalent metal ion species and content of the adhesive are calculated.

  In addition, the kind and content of the acidic group contained in the acidic group-containing polymerizable monomer in the dental adhesive composition are determined from each of the acidic group-containing polymerizable monomers in the composition by preparative high performance liquid chromatography. The molecular weight of each acidic group-containing polymerizable monomer is measured by mass spectrometry, and the structure is determined by nuclear magnetic resonance spectroscopy (NMR) to identify the acidic group and calculate its content. It can be performed.

For example, by measuring ³¹ P NMR, the dialkyl phosphate group can be identified from the chemical shift value. That is, a known compound having a dialkyl phosphate group, specifically, dimethyl phosphoric acid is used as a standard substance, and ³¹ P-NMR is measured for these standard substances under the same conditions (diluting solvent, concentration, temperature). The chemical shift value can be determined by comparing with ³¹ P-NMR measured for the adhesive composition. In addition, methylphosphoric acid is used as a standard substance of a polymerizable monomer having a monoalkyl phosphate group as an acidic group.

  Furthermore, as described above, the polyvalent metal ion is more preferably a trivalent or higher metal ion, particularly a tetravalent metal ion, and most preferably a titanium ion.

The total ionic quantity other than the tetravalent metal ions is preferably 50% or less, particularly 20% or less, based on the total valence quantity of the polyvalent metal ions contained in the composition. That is, the total valence quantity ratio (R ₄₊ ) of tetravalent metal ions (especially titanium ions) to polyvalent metal ions is represented by the following formula (2):
R ₄₊ = TV ₄₊ / TV _{P +} (2)
(Wherein, TV ₄₊ is the total quantity of tetravalent metal ions contained in the composition, and TV _{P +} is the total quantity of polyvalent metal ions contained in the composition as described above. The total quantity-to-quantity ratio (R ₄₊ ) is preferably 0.5 or more, particularly preferably 0.8 or more.

In addition to the specific amount of polyvalent metal ions, the dental adhesive composition of the present invention may contain monovalent metal ions as long as the effects of the present invention are not significantly impaired. good. The total valence of these monovalent metal ions is the total valence of all metal ions contained in the composition (the sum of the total valence of polyvalent metal ions and the total valence of monovalent metal ions). The ratio is preferably 50% or less, particularly 30% or less. That is, the total valence quantity ratio (R ₁₊ ) of monovalent metal ions to all metal ions is expressed by the following formula (3):
R ₁₊ = TV ₁₊ / TV _T ... (3)
( _Wherein TV ₁₊ is the total valence of monovalent metal ions contained in the composition, and TV _T is the total valence of all metal ions contained in the composition). However, the total value-to-quantity ratio (R ₁₊ ) is preferably in the range of 0.5 or less, particularly 0.3 or less. When a large amount of monovalent metal ions coexist, the development of ionic bonds by polyvalent metal ions is impaired by the neutralization reaction between the monovalent metal ions and the acidic groups of the acidic group-containing polymerizable monomer. This is because there is a risk of losing.

  In the adhesive composition for a tooth of the present invention, the method for containing a polyvalent metal ion in the composition is not particularly limited, and when preparing the adhesive composition for a tooth, an acidic group-containing polymerization is performed. A substance serving as an ion source of the polyvalent metal ion may be blended or brought into contact with the functional monomer component to elute the polyvalent metal ion.

  Examples of the polyvalent metal ion source include a polyvalent metal ion-eluting filler containing ions that elute the polyvalent metal ions. As the polyvalent metal ion source, polyvalent metal ion compounds such as metal salts and metal alkoxides can also be used. Metal salts include 1,3-diketone enol, citrate, tartrate, fluoride, malonate, glycolate, lactate, phthalate, isophthalate, terephthalate, acetate, And methoxyacetate. Examples of the metal alkoxide include metal methoxide, metal ethoxide, metal propoxide, metal isopropoxide and the like. Among these polyvalent metal ion compounds, lower polyvalent metal alkoxides having 4 or less carbon atoms have a fast elution of metal ions, and since the by-product is alcohol, the adhesive strength is not affected and the by-product can be easily removed. It is more preferable because it is easy to handle. In addition, since some of these polyvalent metal ion compounds have remarkably low solubility, it is preferable to use them after confirming in advance by a preliminary experiment or the like.

  In addition, polyvalent metal as a polyvalent metal ion source and its oxides are often insoluble in a polymerizable monomer or an organic solvent, and are generally almost compatible even in the presence of water. Therefore, it is usually difficult to use as a polyvalent metal ion source material. In general, strong acid salts tend to be difficult to exchange salts with weak acids. Therefore, when a metal salt is used as the polyvalent metal ion compound, the pKa value of the acidic group of the acidic group-containing polymerizable monomer (phosphoric acid or the like that dissociates in multiple stages is the pKa value based on the first dissociation). It is preferable to select and use an acid having a high pKa, that is, a metal salt of a weak acid from the acidic group-containing polymerizable monomer. That is, even when using a salt of a stronger acid than the acidic group-containing (meth) acrylate polymerizable monomer, the released polyvalent metal ion and the acidic group of the acidic group-containing (meth) acrylate polymerizable monomer This is not preferable because ionic bonds are not sufficiently generated.

  The adhesive composition for tooth according to the present invention is preferably produced using a polyvalent metal alkoxide as the polyvalent metal ion source from the viewpoint of ease of production. That is, the acidic group-containing polymerizable monomer and the polyvalent metal alkoxide are first mixed and then mixed with water. When a polymerizable monomer other than the acidic group-containing polymerizable monomer is blended, the other polymerizable monomer is first mixed with the acidic group-containing polymerizable monomer, and then a polyvalent metal. What is necessary is just to mix with an alkoxide and then with water. Alternatively, the acidic group-containing polymerizable monomer and the polyvalent metal alkoxide may be mixed first, and then mixed finally with water.

  Mixing of the acidic group-containing polymerizable monomer and the polyvalent metal ion compound needs to be performed in the absence of water. When these are mixed in the presence of water, the polyvalent metal ions usually precipitate as solid oxides, and it becomes impossible to form an ionic bond with an acidic group. That is, when an acidic group-containing polymerizable monomer and a polyvalent metal ion compound are mixed in the presence of water, sufficient adhesive strength cannot be obtained even if the composition is used immediately after the composition is prepared. Therefore, it is necessary to mix water after mixing the acidic group-containing compatible monomer and the polyvalent metal ion compound in advance and forming a sufficient ionic bond therebetween.

<(C) Water>
In the present invention, (C) water has a function as a solvent for uniformly dispersing various components, and at the same time, demineralization of teeth, (A) an acidic group-containing polymerizable monomer, and (B) Necessary for promoting ionic bonds with polyvalent metal ions. Since these waters are applied to the teeth during use of the adhesive composition and sufficiently decalcified, they are dried by air blowing, so that almost all of them are removed during the polymerization reaction.

  The greatest feature of the present invention resides in that water containing 10% by mass or more of heavy water is used. Thereby, even if a composition is stored for a long time, the gelation can be suppressed. The reason is not clear, but it is estimated as follows. That is, since heavy water molecules have a larger mass and a lower motion speed than ordinary water molecules, reaction rates in various chemical reactions are generally slower than ordinary water molecules (isotope effect). This effect has some influence, and even in the dental adhesive composition of the present invention, the formation of ionic crosslinks that caused gelation during storage proceeds gently when water is contained in the large amount of heavy water. This is thought to be because of this. Even if the ionic cross-linking reaction during storage progresses gently as described above, the ionic cross-linkage develops at once with the concentration and drying after application to the tooth surface, so that the ionic cross-linking reaction is high. Adhesive strength is maintained well.

As heavy water, D ₂ O is generally used, but D ₂ ¹⁷ O, D ₂ ¹⁸ O, HDO, HD ¹⁷ O, HD ¹⁸ O, H ₂ ¹⁷ O, and H ₂ ¹⁸ O can be used in the same manner. These may be used alone or in appropriate combination of two or more. Water other than heavy water (light water) can be used without limitation as long as it does not substantially contain impurities that are harmful to storage stability and medical ingredients, and may be tap water. Ionized water is used.

  In addition, although heavy water is contained in normal water, its content is very small (usually about 0.26% by mass) and is clearly distinguished from water containing a large amount of heavy water used in the present invention. However, in such a small amount, the above-mentioned gelation suppressing effect does not appear. From the viewpoint of sufficiently exhibiting the effect of suppressing the decrease in viscosity, the content of heavy water in water is more preferably 50% by mass or more.

  The content of water containing a large amount of heavy water contained in the dental adhesive composition of the present invention is 10 to 120 parts by mass, particularly 50 to 100 parts by mass with respect to 100 parts by mass of the acidic group-containing polymerizable monomer. Is preferred. If the amount of water is less than this range, tooth decalcification and ionic bonds are not sufficient, and high adhesive strength is difficult to obtain. Also, if it is used in a larger amount than the above range, the removability by air blow after applying this adhesive composition to the tooth surface will be reduced, and a lot of water will remain on the tooth surface, and sufficient adhesive strength Cannot be obtained.

<(D) Acidic group-free polymerizable monomer>
The dental adhesive composition of the present invention contains (E) an acidic group-free polymerizable monomer in addition to the (A) acidic group-containing polymerizable monomer as a polymerizable monomer component. You may do it. These acidic group-free polymerizable monomers adjust the strength of the adhesive interface and the permeability of the pretreatment material to the tooth, depending on the purpose such as giving better adhesive strength to the tooth, It is only necessary to use various types.

  As the non-acidic group-containing polymerizable monomer that can be used in the present invention, any known monomer can be used without any limitation as long as it is a compound having at least one polymerizable unsaturated group in the molecule. Specific examples include methyl (meth) acrylate (meaning methyl acrylate or methyl methacrylate; the same shall apply hereinafter), ethyl (meth) acrylate, glycidyl (meth) acrylate, 2-cyanomethyl (meth). Acrylate, benzyl (meth) acrylate, polyethylene glycol mono (meth) acrylate, allyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, glycidyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, glyceryl mono (meta ) Acrylate, mono (meth) acrylate monomers such as 2- (meth) acryloxyethyl acetylacetate; ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethyl Glycol di (meth) acrylate, nonaethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, 2,2′-bis [4- (meth) acryloyloxyethoxyphenyl ] Propane, 2,2′-bis [4- (meth) acryloyloxyethoxyethoxyphenyl] propane, 2,2′-bis {4- [3- (meth) acryloyloxy-2-hydroxypropoxy] phenyl} propane, Polyfunctional (meta) such as 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, urethane (meth) acrylate, and epoxy (meth) acrylate ) Acrylate-based single amount And the like can be given.

  Furthermore, it is also possible to mix and polymerize a polymerizable monomer other than the (meth) acrylate monomer as the acidic group-free polymerizable monomer. Examples of these other polymerizable monomers include fumaric acid ester compounds such as dimethyl fumarate, diethyl fumarate and diphenyl fumarate; styrene such as styrene, divinylbenzene, α-methylstyrene, α-methylstyrene dimer, α-methylstyrene derivatives; allyl compounds such as diallyl phthalate, diallyl terephthalate, diallyl carbonate, allyl diglycol carbonate and the like. These polymerizable monomers can be used alone or in admixture of two or more.

  In addition, when a highly hydrophobic polymerizable monomer is used, an amphiphilic monomer such as 2-hydroxyethyl (meth) acrylate or 2-hydroxypropyl (meth) acrylate is used to separate water. It is preferable in terms of adhesive strength to prevent the above and to have a uniform composition.

  The compounding amount of such an acidic group-free polymerizable monomer is 500 parts by mass or less, more preferably 350 parts by mass or less, with respect to 100 parts by mass of the acidic group-containing polymerizable monomer component. It is preferable from the viewpoint of sufficiently exhibiting the blending effect of the group-containing polymerizable monomer.

<(E) Volatile organic solvent>
The dental adhesive of the present invention may further contain a volatile organic solvent. As the volatile organic solvent, those which are volatile at room temperature and water-soluble can be suitably used. The term “volatile” as used herein means that the boiling point at 760 mmHg is 100 ° C. or lower and the vapor pressure at 20 ° C. is 1.0 KPa or higher. The term “water-soluble” means that the solubility in water at 20 ° C. is 20 g / 100 ml or more, and it is preferably compatible with water at 20 ° C. in an arbitrary ratio.

  Examples of such volatile water-soluble organic solvents include methanol, ethanol, n-propanol, isopropyl alcohol, tertiary butanol, acetone, and methyl ethyl ketone. A plurality of these organic solvents can be mixed and used as necessary. In view of toxicity to the living body, ethanol, isopropyl alcohol and acetone are preferable.

  The compounding amount of these volatile organic solvents is usually in the range of 100 to 600 parts by mass, more preferably 200 to 500 parts by mass with respect to 100 parts by mass of the acidic group-containing polymerizable monomer. These volatile organic solvents are also removed by air blowing before the adhesive is cured when the dental adhesive of the present invention is applied to the tooth surface, similarly to the water. is there.

<(F) Polymerization initiator>
An effective amount of a polymerization initiator may be added to the dental adhesive of the present invention, and is particularly necessary when used as a dental adhesive. Such a polymerization initiator is preferably a photopolymerization initiator because it can be polymerized and cured at an arbitrary timing.

  As photopolymerization initiators, α-diketones such as camphorquinone, benzyl, α-naphthyl, acetonaphthene, naphthoquinone, 1,4-phenanthrenequinone, 3,4-phenanthrenequinone, 9,10-phenanthrenequinone; 2,4 -Thioxanthones such as diethylthioxanthone; 2-benzyl-dimethylamino-1- (4-morpholinophenyl) -butanone-1, 2-benzyl-diethylamino-1- (4-morpholinophenyl) -butanone-1, 2 -Benzyl-dimethylamino-1- (4-morpholinophenyl) -propanone-1,2-benzyl-diethylamino-1- (4-morpholinophenyl) -propanone-1,2-benzyl-dimethylamino-1- ( 4-morpholinophenyl) -pentanone-1,2-benzyl-die Α-aminoacetophenones such as tilamino-1- (4-morpholinophenyl) -pentanone; 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis (2,6-dimethoxybenzoyl) -2,4,4- Acylphosphine oxide derivatives such as trimethylpentylphosphine oxide are preferably used.

  Further, borate compounds such as sodium salt of tributyl boric acid, tetraphenyl boric acid, or tetrakis (p-tolyl) boric acid, or triethanolammonium salt, dibenzoyl peroxide, di (4-methylbenzoyl) Chemical polymerization initiators such as diacyl peroxides such as peroxides, alkyl hydroperoxides such as t-butyl hydroperoxide, 1,1,3,3-tetramethylbutyl hydroperoxide, and barbituric acids are also required. May be added.

  Furthermore, a transition metal compound such as a vanadium compound, a chromium compound, a manganese compound, an iron compound, or a cobalt compound may be used at the same time for the purpose of increasing the polymerization initiation activity of hydroperoxides and / or borates. Preferred are vanadium compounds such as oxovanadium (IV) bis (maltolate) and divanadium pentoxide.

  Examples of the polymerization accelerator that can be used in combination with the polymerization initiator include N, N-dimethylaniline, N, N-diethylaniline, N, N-di-n-butylaniline, N, N-dibenzylaniline. N, N-dimethyl-p-toluidine, N, N-diethyl-p-toluidine, N, N-dimethyl-m-toluidine, p-bromo-N, N-dimethylaniline, m-chloro-N, N- Dimethylaniline, p-dimethylaminobenzaldehyde, p-dimethylaminoacetophenone, p-dimethylaminobenzoic acid, p-dimethylaminobenzoic acid ethyl ester, p-dimethylaminobenzoic acid amyl ester, N, N-dimethylanthranic acid methyl ester N, N-dihydroxyethylaniline, N, N-dihydroxyethyl-p-tolu Gin, p-dimethylaminophenethyl alcohol, p-dimethylaminostilbene, N, N-dimethyl-3,5-xylidine, 4-dimethylaminopyridine, N, N-dimethyl-α-naphthylamine, N, N-dimethyl-β -Naphtylamine, tributylamine, tripropylamine, triethylamine, N-methyldiethanolamine, N-ethyldiethanolamine, N, N-dimethylhexylamine, N, N-dimethyldodecylamine, N, N-dimethylstearylamine, N, N- Tertiary amines such as dimethylaminoethyl acrylate, N, N-dimethylaminoethyl methacrylate, 2,2 ′-(n-butylimino) diethanol; 5-butyl barbituric acid, 1-benzyl-5-phenylbarbituric acid Barbituric acids such as Mention may be made of dodecyl mercaptan, pentaerythritol tetrakis (thioglycolate) mercapto compounds, and the like. Furthermore, in order to further increase the polymerization initiation activity, an electron acceptor such as an iodonium salt, a trihalomethyl-substituted S-triazine, or a phenacylsulfonium salt compound may be added in addition to the above polymerization initiator and polymerization accelerator.

  The blending amount of the polymerization initiator is not limited as long as it is an effective amount. Usually, however, including the blending amount of a polymerization accelerator, an electron acceptor, and the like, with respect to 100 parts by mass of the acidic group-containing polymerizable monomer. The range of 0.1-50 mass parts is preferable, and the range of 1-20 mass parts is more preferable.

  The dental adhesive of the present invention may further contain a filler. Preferred examples of the filler include inorganic fillers such as silica, zirconia, titania, silica / zirconia, and silica / titania.

  These inorganic fillers can be hydrophobized with a surface treatment agent typified by a silane coupling agent, thereby improving compatibility with the polymerizable monomer and improving mechanical strength and water resistance. The hydrophobization method may be carried out by a known method. Examples of the silane coupling agent include methyltrimethoxysilane, methyltriethoxysilane, methyltrichlorosilane, dimethyldichlorosilane, trimethylchlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane. , Vinyltrichlorosilane, vinyltriacetoxysilane, vinyltris (β-methoxyethoxy) silane, γ-methacryloyloxypropyltrimethoxysilane, γ-methacryloyloxypropyltris (β-methoxyethoxy) silane, γ-chloropropyltrimethoxysilane, γ-chloropropylmethyldimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, β- (3,4-epoxycyclohexyl) Trimethoxysilane, N- phenyl--γ- aminopropyltrimethoxysilane, etc. hexamethyldisilazane is preferably used.

  The blending amount of the inorganic filler is usually preferably in the range of 2 to 400 parts by weight, more preferably in the range of 5 to 100 parts by weight, and 5 to 40 parts by weight with respect to 100 parts by weight of the acidic group-containing polymerizable monomer. Part ranges are particularly preferred.

  Furthermore, an organic thickener such as a polymer compound such as polyvinyl pyrrolidone, carboxymethyl cellulose, or polyvinyl alcohol is added to the adhesive of the present invention as needed, regardless of the application, as long as the performance is not deteriorated. It is possible. Various additives such as ultraviolet absorbers, dyes, antistatic agents, pigments, and fragrances can be selected and blended as necessary.

  The dental adhesive composition of the present invention may be produced by uniformly mixing the various components described above. Since it can be stored for a long time in the form of one liquid, that is, in the form of a single package, there is no need for troublesome operations of mixing the components during use, reducing the labor of the dentist, etc., and stable and constant adhesion Strength can be secured. The storage is preferably refrigerated at 0 to 10 ° C.

  In the adhesive composition of the present invention thus obtained, a type in which the photopolymerization initiator (F) is not blended is used as a tooth pretreatment material. This pretreatment material has functions of both tooth etching treatment and tooth penetration promotion treatment, and it is used as a self-etching primer for adhesion of prosthesis to the tooth in addition to composite resin and bracket. it can. For example, before applying a composite resin adhesive, a bracket adhesive, or a prosthetic adhesive, it may be applied to a tooth.

  On the other hand, the type in which the photopolymerization initiator (F) is blended is used as a dental adhesive such as the above composite resin adhesive, bracket adhesive, or prosthetic adhesive. These dental adhesives may be chemically polymerized, but the composite resin and bracket adhesives are preferably photo-curing types from the standpoint of ease of operation.

  Hereinafter, in order to specifically describe the present invention, examples and comparative examples will be described. However, the present invention is not limited to these examples. In addition, the abbreviations of the compounds used in Examples and Comparative Examples shown in Examples are as follows.

(A) Acidic group-containing polymerizable monomer PM1: 2-methacryloyloxyethyl dihydrogen phosphate PM2: bis (2-methacryloyloxyethyl) hydrogen phosphate MDP: 10-methacryloyloxydecyl dihydrogen phosphate

(B) Multivalent metal ion Al (O-iPr) ₃ : Aluminum triisopropoxide Ti (O-iPr) ₄ : Titanium tetraisopropoxide

(D) Acidic group-free polymerizable monomer Bis-GMA: 2,2′-bis [4- (2-hydroxy-3-methacryloxypropoxy) phenyl] propane 3G: triethylene glycol dimethacrylate HEMA: 2- Hydroxyethyl methacrylate

(E) Polymerization initiator CQ: camphorquinone DMBE: ethyl p-N, N-dimethylaminobenzoate Inorganic filler F1: amorphous silica having an average particle size of 0.02 μm (treated with methyltrichlorosilane)
In the following examples and comparative examples, various measurements were performed by the following methods.

(1) Measuring method of polyvalent metal ions After adjusting the dental adhesive of the present invention and stirring for 24 hours, 0.2 g was weighed into a 100 ml sample tube and diluted to 0.1% by mass with acetone. did. This liquid was filtered with a syringe filter, and the concentration of each metal ion (mmol / g) contained per 100 parts by mass of the polymerizable monomer was measured using ICP (inductively coupled plasma) emission spectrometry. . Each metal ion concentration was converted using a calibration curve obtained from a standard sample (1 ppm, 2.5 ppm, 6 ppm) of each ion.

(2) Measuring method of tooth adhesion a) Preparation method of adhesion test piece The bovine front teeth are removed within 24 hours after slaughter, and enamel and parallel to the lip surface with # 600 emery paper under running water. The dentin plane was cut out. Next, these surfaces were dried by blowing compressed air for about 10 seconds, and then a double-sided tape with a hole having a diameter of 3 mm was fixed to any surface of enamel and dentin, and then the thickness was 0.5 mm. A paraffin wax having a hole of 8 mm was fixed on the circular hole so as to have the same center, thereby forming a simulated cavity. A dental adhesive is applied to the simulated cavity, left for 20 seconds, dried by blowing compressed air for about 10 seconds, and then lighted for 10 seconds with a dental visible light irradiator (Tokuso Power Light, manufactured by Tokuyama Corporation). Irradiated. Further, a dental composite resin (Esterite Σ, manufactured by Tokuyama Dental Co., Ltd.) was filled thereon, and irradiated with a visible light irradiator for 30 seconds to prepare an adhesion test piece.
b) Adhesion test method The above-mentioned adhesion test piece was immersed in water at 37 ° C for 24 hours, and then pulled at a crosshead speed of 2 mm / min using a tensile tester (Autograph, manufactured by Shimadzu Corporation). Tensile bond strength was measured. With respect to four test pieces per test, the tensile bond strength was measured by the above-described method, and the average value was used as the bond strength to enamel or dentin to evaluate the tooth adhesion.

(3) Storage stability evaluation method of adhesive material After the adjustment, the dental adhesive material of the present invention stored in an incubator at 37 ° C was observed over time for 6 months, and the presence or absence of gelation of the liquid was changed visually. There were no evaluations, and the evaluation was made in four stages: no increase, viscosity increased, gelled but applicable Δ, completely solidified ×. Moreover, using the adhesive material preserve | saved in a 37 degreeC incubator, the adhesive strength was measured over time using the same method as the above-mentioned adhesion strength measuring method, and it compared with the adhesive strength before 37 degreeC preservation | save.

Example 1
As acidic group-containing polymerizable monomer, 10 g of PM1, as polyvalent metal ion source, 2.5 g of Al (O-iPr) ₃ , as water, 8 g of heavy water containing 50% by mass of water, 12 g of Bis-GMA, 8 g of 3G, and 10 g of HEMA as the polymerizable monomer containing, 34 g of acetone as the volatile organic solvent, 0.4 g of CQ as the polymerization initiator, and 0.4 g of DMBE Were weighed and mixed with stirring for 24 hours to obtain the dental adhesive of the present invention. After measuring the amount of polyvalent metal ions and the adhesion strength to enamel and dentin, the adhesive was stored in an incubator at 37 ° C., and the presence or absence of gelation of the liquid was observed over time. In addition, the adhesion strength to enamel and dentin was also evaluated over time. Table 1 shows the composition of the dental adhesive, and Table 2 shows the storage stability evaluation results (evaluation of the presence or absence of gelation and adhesion strength to enamel and dentin).

Examples 2 to 19
The storage stability was evaluated according to the method of Example 1 except that dental adhesives having different compositions shown in Table 1 were prepared. The composition of the dental adhesive is shown in Table 1, and the storage stability evaluation results are shown in Table 2.

Comparative Examples 1 to 5
Storage stability was evaluated according to the method of Example 1 except that dental adhesives having different compositions shown in Table 3 were prepared. The composition of the dental adhesive is shown in Table 3, and the storage stability evaluation results are shown in Table 4.

  Examples 1 to 19 are dental adhesives formulated so as to satisfy all of the requirements described in the claims of the present invention, but in storage stability evaluation at 37 ° C. for 6 months, In any case, although the viscosity increased, the liquid did not gel, the adhesion to enamel and dentin was good, and no significant deterioration was observed in its storage stability.

  On the other hand, Comparative Examples 1 and 2 are cases where normal water that does not significantly contain heavy water is used as water, but in either case, the liquid gels and the liquid gels. , Adhesion decreased.

  Further, Comparative Example 3 is a case containing no water at all, but the tooth decalcification effect was not obtained, and further, ions of (A) an acidic group-containing polymerizable monomer and (B) a polyvalent metal ion. Since bonding is not promoted, adhesion to the tooth is greatly reduced.

  In Comparative Example 4, water containing 8% by mass of heavy water was used, but the gelation of the liquid was faster than that of the example, and the adhesiveness decreased faster accordingly.

  Further, Comparative Example 5 is a case where no (B) polyvalent metal ions were contained, but since the effect of ionic crosslinking was not obtained, the adhesion to enamel and dentin was greatly reduced.

Claims (5)

(A) an acidic group-containing polymerizable monomer,
A dental adhesive composition comprising (B) polyvalent metal ions and (C) water containing 10% by mass or more of heavy water. The dental adhesive according to claim 1, wherein the content of water containing 10 mass% or more of (C) heavy water is 10 to 120 mass parts with respect to 100 mass parts of (A) acidic group-containing polymerizable monomer. Sex composition. (A) With respect to 100 parts by mass of the acidic group-containing polymerizable monomer, (B) the polyvalent metal ion is represented by the following formula (1):
R _{P +} = TV _{P +} / TV _A (1)
(Wherein TV _{P +} is the total valence of (B) polyvalent metal ions contained in the composition, and TV _A is the (A) acidic group-containing polymerizable monomer contained in the composition. The dental value according to claim 1 or 2, wherein the total value-quantity ratio (R _{P +} ) defined by (the total value of acid groups) is 0.1 to 1.5. Adhesive composition. The dental adhesive composition according to any one of claims 1 to 3, further comprising (D) an acidic group-free polymerizable monomer component. Furthermore, (E) Dental adhesive composition as described in any one of Claims 1-4 which comprises a volatile organic solvent.