JP2578212B2 - Maleic acid monoester compounds and adhesives containing them - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a novel maleic acid monoester compound and a dental adhesive containing the same. More specifically, as a dental adhesive, an adhesive resin cement or an orthodontic adhesive which is itself adhesive, and a dental material for enhancing the adhesion between a tooth such as a filler such as a normal composite resin or a dental material, and the like. For adhesives.

[Conventional technology]

In recent years, composite resins have been developed as alternatives to dental cements such as zinc phosphate cement and silicate cement for the treatment of dental caries, and recently, stable water absorption and low disintegration over a long period of time Colors that are indistinguishable from natural teeth are also being made. However, since the composite resin does not essentially adhere to tooth enamel and dentin, a gap is created between the tooth material and the filled composite resin in a long period of time,
Secondary caries tended to occur and eventually the composite resin fell off.

Conventionally, various adhesion improvers such as an adhesive liner have been developed to improve the adhesion between such a composite resin and the cavity wall, and a tooth material such as an adhesive caries preventive / closing agent and an orthodontic adhesive has been developed. There have been proposed various dental adhesive compositions intended to adhere to dental materials.

[Problems to be solved by the invention]

However, few of these conventional products are moist as in the mouth and strongly adhere to the teeth for a long period of time in an environment where the temperature changes drastically. For example, an adhesive mainly composed of α-cyanoacrylate has been developed as an anti-caries filler and an orthodontic adhesive for the purpose of adhering to the dentin, but has a durability in the oral cavity. It is said that there is a problem in operability during use.

On the other hand, fillers containing bisphenol A diglycidyl methacrylate as a main component of the resin and curing with a benzoylamine peroxide-based catalyst have been widely used in recent years.
However, it does not have adhesive properties to dentin and enamel, so when it is filled in the tooth dents, the filler may drop off after a while, or it may induce the occurrence of secondary caries .

Further, it has been proposed that an adhesive containing 2-methacryloyloxyethyl trimellitic anhydride has excellent water resistance and durability, and can sufficiently withstand use in the oral cavity.
However, the room temperature polymerization catalyst used for this adhesive is generally practically limited to tri-n-butylborane oxide, and has an advantage of having strong adhesion to tooth dentin, but the polymerization reaction rate is low. It takes more than ten minutes to final cure,
Further, it is said that there are many problems from the standpoint of dental clinic, such as difficulty in handling because it is extremely unstable in air.

As described above, there is still no dental material that has adhesive strength to both dentin and enamel, and shows strong adhesive strength over a long period of time even in an environment where the oral cavity is wet and the temperature changes drastically. It has not been.

In view of the above-mentioned conventional technology, the present inventors have the necessary physical and engineering properties as a dental adhesive, such as hardness, compressive strength, water absorption and the like, and have excellent adhesion to dentin and enamel. Intensive study was conducted to obtain a strong dental adhesive. As a result, those obtained by polymerizing and curing a maleic acid monoester compound having a specific structure have a strong adhesive force to teeth even in water, and a polymer of a maleic acid monoester compound or a maleic acid monoester compound. When the copolymer with the other polymerizable monomer itself is used as a tooth and a filler, it is strongly adhered to the tooth wall and there is no gap formation or filler drop due to poor adhesion, In addition, when used as a coating agent or an adhesive for a filler such as a composite resin, it can significantly improve marginal sealing properties and can effectively prevent the occurrence of secondary caries, such as adhesion of teeth. The present invention has been found to be suitable for the present invention.

[Means for solving the problem]

According to the present invention, the following general formula (1) (However, R ₁ or R ₂ represents —H or —CH ₃ , m or n
Represents 1, 2 or 3. A) providing a maleic acid monoester compound represented by the formula:
Also provided is a dental adhesive comprising the maleic acid monoester compound or a homopolymer thereof, or a copolymer of the maleic acid monoester compound and another vinyl monomer.

 Hereinafter, the present invention will be described in detail.

The compound represented by the above general formula (1) is a novel compound and is usually synthesized from maleic anhydride and a hydroxyalkyl ester of acrylic (or methacrylic) acid as shown in the following formula (2).

In general, the synthesis is carried out by reacting a mixture of maleic anhydride and a hydroxyalkyl ester of acrylic (or methacrylic) acid, which are substantially equimolar, with a raw material at a temperature of 50 to 70 ° C. under heating and stirring.

The resulting maleic acid monoester compound exhibits a wave number (ν _max ) of 1720 cm ⁻¹ in an infrared absorption spectrum (IR) of a carbonyl group, which is a characteristic of maleic acid, and an IR wave number (ν) of an acryloyl (methacryloyl) group. _max ) 1
640 cm ^-1 and IR wavenumber of the oxyalkyl group (ν _max ) 1170 cm
^-1 clearly indicates that the compound has an acryloyl (methacryloyl) group and an oxyalkyl group in the compound molecule. More detailed structures can be identified by nuclear magnetic resonance spectra (NMR).

The maleic acid monoester compound of the present invention obtained by the above method is useful as a dental adhesive, industrial adhesive, thermosetting paint, paper processing, lubricating oil additive, fiber treatment agent (charge Prevention, etc.), a flame retardant, a metal binding solvent, a metal extractant and the like. The dental adhesive containing the maleic acid monoester compound or polymer represented by the general formula (1) contains the maleic acid monoester compound as a polymerizable monomer alone or together with another vinyl monomer. May be used, or may contain a homopolymer of a maleic acid monoester compound or a copolymer with another vinyl monomer, or may contain a mixture of these polymers and a vinyl monomer. It may be something. Normally, the adhesive is adhered to the teeth by hardening at the time of use.

The tooth adhesive of the present invention is characterized in that it is a maleic acid monoester represented by the formula (1), and the enamel is combined with the action of the maleic acid residue and other functional groups of the maleic acid monoester compound. While maintaining excellent adhesive strength, and exhibiting excellent properties in adhesive strength to dentin. The reason for the excellent adhesion to dentin is that
It is presumed that the balance between the hydrophilic group and the hydrophobic group of the maleic acid monoester compound of the formula (1) is attributable to a suitable arrangement with respect to the affinity for organic substances such as collagen.

Examples of the compound represented by the formula (1) useful for the dental adhesive of the present invention include the following.

In the dental adhesive of the present invention, in addition to the above-mentioned constituent components, known components which are usually compounded according to the type of the material to be bonded and the purpose of use can be used.

For example, when used as an adhesive filler, only the maleic acid monoester compound of the formula (1) is used as a polymerizable monomer, and the adhesive filler is polymerized and cured in the presence of a curing agent at the time of use. Can be used as However, usually, a mixture of the maleic acid monoester compound of the formula (1) and another polymerizable monomer is used, and is polymerized and cured in the presence of a curing agent when used. In this case, the other polymerizable monomers include methyl methacrylate, hydroxyethyl methacrylate, ethylene glycol di-methacrylate, di- or tri- or tetraethylene glycol di-methacrylate, glycidyl methacrylate, 2,2-bis (4 -Methacryloxyphenyl) propane, 2,2-bis [4- (3-methacryloxy-2-
[Hydroxypropoxy) phenyl] propane, styrene, 1,3-butanediol dimethacrylate, tetrahydrofurfuryl methacrylate, trimethylolpropane trimethacrylate, and vinyl monomers such as bisoxyethylenated bisphenol A diacrylate are used.

If necessary, a polymerizable monomer polymer and / or oligomer containing the maleic acid monoester compound of formula (1) may be blended for adjusting the viscosity, curing rate, polycondensation and the like. Furthermore, inorganic fillers such as silica, glass beads, alumina, and quartz powder (preferably having a particle size of 100 μm or less) or the above fillers for improving the bonding property with the resin are used as γ-methacryloxypropyltrimethoxysilane, vinyltrichlorosilane, Those treated with a silane coupling agent such as vinyltriethoxysilane, or a desired additive such as a curing agent, a polymerization inhibitor, a coloring agent, an antioxidant, or an ultraviolet absorber may be used.

When an amine and a peroxide or a p-toluenesulfinate and a peroxide are used in combination as a curing agent, the maleic acid monoester compound of the formula (1) is divided into two equal parts as a polymerizable monomer. A curing agent such as an amine or p-toluenesulfinate is used on one side, and a curing agent such as a peroxide is added on the other side, and the maleic acid monoester compound of the formula (1) and another polymerizable monomer are used. When used as a mixture, one of the curing agents is similarly added to each of the two equal parts of the other polymerizable monomers, and the maleic acid monoester compound of the formula (1) is added with the curing agent. It is preferable to use a mixture with one or both of the other polymerizable monomers divided into two equal parts. These curing agents are usually mixed and used at the time of use.

The blending amount of the maleic acid monoester compound of the formula (1) is not particularly limited, but when used together with another polymerizable monomer, it is 10 to 100% (% by weight, hereinafter the same as the other polymerizable monomer). ), Preferably 20 to 90%. If it is less than 10%, the adhesive effect is poor, which is not preferable. The amount of the polymerizable monomer is preferably 15 to 100% based on the whole adhesive composition, and the amount of the inorganic filler is preferably 0 to 85% based on the whole adhesive composition.

The dental adhesive of the present invention is applied to a tooth and a conventional composite
When used as an adhesive with fillers such as resin,
In an organic solvent such as ethyl ether or chloroform (1)
The maleic acid monoester compound of the formula can be used by containing 20 to 90%. Further, the other polymerizable monomer may contain the maleic acid monoester compound of the formula (1) in an amount of 20 to 90%. Further, it can be used in the same manner as when it is used as the above-mentioned filler.

When the dental adhesive of the present invention is used as a filler, the adhesive is filled in the cavity to be filled and cured. When used for bonding dental fillings to teeth, for example, after forming a cavity, apply the adhesive to the cavity wall, fill the prescribed filling material, and then harden. Can be.

〔Example〕

Hereinafter, the present invention will be described in more detail based on examples. However, the present invention is not limited to these examples.

The analytical measurement of the synthetic compound and the like in this example was performed by the following method.

[1] Elemental analysis (EA) Carbon was analyzed using Perkin-Elmer 240 type elemental analyzer.
Measure hydrogen.

[2] Infrared absorption spectrum (IR) Measured by a liquid film method using a sodium chloride plate with a Perkin-Elmer 1750 infrared absorption spectrograph.

[3] Nuclear Magnetic Resonance Spectrum (NMR) Measured with a GX-270 type nuclear magnetic resonance spectrum analyzer manufactured by JEOL Ltd. using heavy chloroform as a solvent and tetramethylsilane as a reference substance.

Example 1 Compound Was synthesized.

2-hydroxy-1,3-dimethacryloxypropane 45.
A mixture of 7 g and 19.6 g of maleic anhydride was reacted by heating and stirring at 60 ° C. for 48 hours.

After the reaction, the mixture was allowed to cool, and 350 ml of a 5% aqueous sodium carbonate solution was added to obtain an aqueous solution. The aqueous solution was washed with 500 ml of ethyl ether in four portions. After washing, add 5% hydrochloric acid to this aqueous solution
The pH was adjusted to 2-3, and the oil was separated from the aqueous layer.
This oil was extracted with 250 ml of ethyl acetate. After the extract was washed with distilled water, it was dehydrated and dried with sodium sulfate overnight. Thereafter, the ethyl acetate was removed by distillation under reduced pressure to remove the oily substance.
9.9 g were obtained.

 The analysis results of the obtained oil were as follows.

EA (%): C 55.35, H 5.41 Theoretical value: C 55.21, H 5.56 NMR ( CDCl 3); δ (ppm): 10.10 (bs1H; -COOH) 6.35 (s2H; -CH = CH-) 6.10,5.60 ( _{d4H; CH 2 =) 5.45 (} m1H; -CH-) 4.40 (m4H; -COOCH 2 -) 1.95 (s6H; -CH 3) IR ν max (cm -1): 1730,1640,1460,1170 example 2 [Preparation of Adhesive] 60% of the compound obtained in Example 1, 10% of 2-hydroxyethyl methacrylate (hereinafter, referred to as HEMA), 2,2
-Bis [4- (3-methacryloxy-2-hydroxypropoxy) phenyl] propane (hereinafter referred to as Bis-GMA) 15%, triethylene glycol dimethacrylate (hereinafter referred to as TEGDMA) 14% and benzoyl peroxide (hereinafter referred to as benzoyl peroxide) A two-part adhesive was prepared by using a solution consisting of 1% as solution A, and an ethanol solution containing 4% of sodium p-toluenesulfinate and 1% of dimethyl-p-toluidine as solution B. did.

(Adhesion between dentin and composite resin)

For the experimental teeth, the bovine teeth obtained in a state of being implanted in the jaw bone immediately after sacrifice were extracted, the tissues around the attached teeth were removed, and the crown and root were diamond-cut with a diamond cutter (Malteau cutter MC-100). ), And the crown pulp was removed, and the pulp was stored frozen and thawed when necessary.

Hereinafter, the bonding method and the bonding test method will be described in detail based on the example shown in FIG.

Bovine dentin is ground from water-resistant silicon carbide paper coarse to # 600 using Ecomet III (Ecomet III Buehler) under water injection, etched with 65% phosphoric acid for 30 seconds, and then for 30 seconds After washing with water, a test cow tooth was prepared.

In FIG. 1, the bovine tooth 1 adjusted as described above has a diameter
A cellophane tape 2 with a hole of 4 mm is stuck and the area to be adhered is defined. Further, the inside diameter is 6 mm and the height is 5
A plastic ring 3 of mm was fixed with paraffin wax 4.

 Next, a solution prepared by mixing equal amounts of the liquid A and the liquid B prepared above was used.
One layer of adhesive is applied to the surface 5 to be adhered, and ethanol is
After volatilization, light-cured composite resin: Pyro
Fill Light Bond Universal for Front Teeth (Sankin Industries
(Made by) Co., Ltd. in plastic ring 3 to a height of about 2 mm
Fill and light irradiator: Suncure Light (Sankin Industries Co., Ltd.)
) For 30 seconds to form a filling layer 6. Further charging
Chemically polymerizable composite resin on the packing layer 6: Pyro
Fill Bond Front Teeth (Made by Sankin Industries Co., Ltd.)
Forming the filling layer 7 and attaching the metal hook 8 before curing
7. 10 minutes later, immerse in 37 ° C water
Was. After immersion for 24 hours, remove the test cow teeth and conduct a tensile test.
Then, the adhesive strength was measured.

Tensile test was performed using an Autograph DD manufactured by Shimadzu Corporation.
Using an S-500 type testing machine, the bovine tooth 1 and the metal hook 8 were gripped, and the adhesive strength between the bovine dentin 1 and the light-cured composite resin-filled layer 6 was measured at a crosshead speed of 2.0 mm / min. . In this case, the photopolymerizable composite / resin-filled layer 6 and the chemically polymerized composite / resin-filled layer 7 are
Since it adheres strongly, it does not break at the interface with the filling layers 6 and 7. Further, the metal hook 8 does not come off from the filling layer 7.

The adhesive strength was 39 kg / cm ^{2 as} an average value of the tensile test results of the eight test cow teeth prepared as described above.

Comparative Example 1 A test bovine was prepared in the same manner as in Example 6, except that the adhesive of the present invention was not used when preparing the test bovine and the bovine was directly adhered to the light-curable composite resin. Similarly, the adhesive strength was measured. The adhesive strength was 0 kg / cm ² .

Comparative Example 2 HEMA 10%, Bis-GMA 45%, TEGDMA 44% and
The adhesive strength was measured in the same manner as in Example 2 except that a composition comprising 1% of BPO was used. The adhesive strength was 0 kg / cm ² .

Comparative Example 3 The maleic acid monoester compound 60 of the following formula was used as the liquid A.
%, HEMA 10%, Bis-GMA 15%, TEGDMO 14% and BPO 1%, except that the composition was measured in the same manner as in Example 2. The adhesive strength was 19 kg / cm ² .

_{CH 2 = C (CH 3)} -COOCH 2 CH 2 OCOCH = CH-COOH Example 3 A solution as compound 89%, except for using a composition comprising HEAM10% and BPO1% in the same manner as in Example 2 The adhesive strength was measured. The adhesive strength was 32 kg / cm ² .

Example 4 [Adhesion between enamel and composite resin] The adhesive strength was measured in the same manner as in Example 2 except that bovine tooth enamel was used instead of bovine dentin. The adhesive strength was 186 kg / cm ² .

Example 5 [Adhesion between Co-Cr alloy and composite resin] Same as Example 2 except that Co-Cr alloy: Sancorium (manufactured by Sankin Kogyo Co., Ltd.) was used instead of bovine dentin. And the adhesive strength was measured. The adhesive strength was 145 kg / cm ² .

As a pre-treatment of the Co-Cr alloy, it was polished with water-resistant silicon carbide paper under water injection to # 800 in the same manner as in Example 2, then sand-blasted, and then treated with acetone in acetone.
Ultrasonic cleaning was performed for minutes.

〔The invention's effect〕

The maleic acid monoester compound of the present invention is a novel compound, in which a hydrophilic group and a hydrophobic group are present in a well-balanced manner, and thus the physical properties necessary as a dental adhesive, for example, hardness, compressive strength, water absorption, etc. It has excellent properties.

Further, the adhesive containing the maleic acid monoester compound of the present invention has a good adhesion to the dentin of the polymer of the maleic acid monoester compound represented by the formula (1),
High adhesive strength can be maintained for a long period of time even in water or saliva. Therefore, it has good durability in the oral cavity, and firmly adheres to teeth for a long period of time even when used as a filler, for example, in a wet state in the oral cavity and in an environment where temperature changes are drastic. Also, when used as an undercoating agent such as a composite resin or an orthodontic adhesive, the adhesive firmly adheres to the teeth and also strongly adheres to the composite resin or the orthodontic adhesive. Therefore, the gap between the tooth and the tooth can be reliably prevented, the marginal sealing property is improved, and the prevention of secondary caries is completely achieved.

In addition, it can be used as a resin cement having an adhesive property that is insoluble in saliva instead of zinc phosphate cement in which a restoration is attached to an abutment tooth.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a test cow tooth used for measuring the adhesiveness of the compound of the present invention. DESCRIPTION OF SYMBOLS 1 ... cow tooth 2 ... cellophane tape 3 ... plastic ring 4 ... paraffin wax 5 ... adhering surface 6 ... photopolymerization type composite / resin filling layer 7 ... chemical polymerization type composite / resin filling layer 8 ...... Metal hook

Claims (2)

(57) [Claims] 1. The general formula (1) (However, R ₁ or R ₂ represents —H or —CH ₃ , m or n
Represents 1, 2 or 3. And a maleic acid monoester compound represented by the formula: 2. The general formula (1) (However, R ₁ or R ₂ represents —H or —CH ₃ , m or n
Represents 1, 2 or 3. A) a maleic acid monoester compound or a homopolymer thereof, or a copolymer of the maleic acid monoester compound and another vinyl monomer.