KR20040026956A - Trifunctional (Meth)acrylate Ester Monomer and Dental Restorative Compositions Containing the Same - Google Patents

Abstract

PURPOSE: A trifunctional (meth)acrylate ester monomer, its preparation method and a dental restorative composition containing the monomer are provided, to reduce polymerization shrinkage, water absorption and water solubility of a dental restorative composite resin. CONSTITUTION: The trifunctional (meth)acrylate ester monomer is represented by the formula 1, wherein R is H, CH3 or an aromatic or aliphatic hydrocarbon group of C2-C20; R1 is H or CH3; and R2 is CH3 or an aromatic or aliphatic hydrocarbon group of C2-C20. The method comprises the step of reacting the compound of the formula 4 with the compound of the formula 5. Also, another method comprises the step of reacting the compound of the formula 4 with the compound represented by R2COCl in the presence of a catalyst. Preferably the catalyst is triethylamine. The dental restorative composition comprises at least one monomer of the formula 1; and a polymerization initiator. Preferably the polymerization initiator is camphorquinone or benzoyl peroxide.

Description

Trifunctional (Meth) acrylate Ester Monomer and Dental Restorative Compositions Containing the Same}

The present invention relates to a novel organic monomer that can be used as a constituent of the dental composite resin. More specifically, trifunctional meta (a) acrylate ester monomer capable of reducing volume shrinkage and water absorption and water solubility during polymerization, which is a problem of the conventional dental restoration composite resin, and a method of preparing the same It relates to a composition for dental restoration containing.

Amalgam, a silver-tin alloy reacted with mercury, has long been used primarily as a dental restorative material since it was known in the United States in 1883. Amalgam materials have the advantages of being easy to operate, inexpensive, and able to be used for a relatively long time, while the unique colors of metals make the color distinct from natural teeth, resulting in poor aesthetics and risks of mercury to humans and the environment. have. Therefore, while supplementing these shortcomings, organic polymers have emerged as alternative materials having aesthetics and durability and strong bonding to teeth. Since the organic polymer alone does not have sufficient hardness, strength, and abrasion resistance to a degree capable of withstanding mastication pressure, etc., a composite resin in which an organic or inorganic filler is incorporated as a reinforcing material to an organic polymer material is used. The first dental composite resins were made from powders of polymethylmethacrylate ("PMMA") and methylmethacrylate ("MMA") monomers from Kulzer, Germany, in 1942. It has been used in actual clinical practice since it was developed in combination. Such acrylic resins are relatively excellent in mechanical properties, color stability, water resistance, etc., but have disadvantages such as low wear resistance and a large shrinkage upon curing. Recently, inorganic powders are mainly used as fillers for dental composite resins in place of the organic fillers described above.

The damaged tooth is first repaired by mechanically scraping off the damaged area, treating the tooth surface with phosphoric acid, or the like, then applying the undercoat and applying a composite resin thereon. The composite resin is a hydrophobic polymer composite material having good water resistance and high mechanical strength, and contains a large amount of inorganic fillers such as silica to enhance physical properties.

Dental photopolymerizable restorative compositions typically consist of inorganic fillers, prepolymers, diluents, photoinitiators, reducing agents, and other additives, and are capable of withstanding the high occlusal pressures produced when chewing food, and similar thermal expansion rates to teeth. , The same color and luster with natural teeth, and the same feeling as natural teeth when contacted with the tongue for restorative to restore the natural feeling along with physical properties such as low polymerization shrinkage rate to prevent peeling with teeth during polymerization curing Must have such requirements.

The dental composite resin for aesthetic restoration currently used in the dental industry can be roughly divided into two types according to the curing method. The polymerization reaction is performed by mixing two ointments and the polymerization reaction by light irradiation as a single ointment. There is a photocurable type that happens. Photocurable composite resins have been widely used in recent years due to their advantages such as color diversity, color stability, and less bubbles when mixing because they are made of one paste compared to chemically curable composite resins. It is also used in posterior teeth. The composition of the photocurable composite resin generally contains a polyfunctional methacrylate as a prepolymer, an inorganic filler powder such as surface treated silica, a photoinitiator system composed of a photoinitiator and a reducing agent, a dye, and the like. The prepolymers are advantageously low in viscosity in order for the inorganic fillers to be formulated efficiently, thus diluents such as triethylene glycol dimethacrylate (hereinafter referred to as "TEGDMA") for the purpose of lowering the viscosity of the prepolymer. It may be added. The photosensitizer contained in the dental photocurable restorative material absorbs light and initiates a photochemical reaction. As such photoinitiators, camphorquinone (hereinafter referred to as "CQ"), and photoexcited CQ hydrogen N, N-dimethylaminoethyl methacrylate (hereinafter referred to as "DMAEMA") and ethyl 4-dimethylaminobenzoate (ethyl 4-dimethylaminobenzonate) as a reducing agent which actually starts radical polymerization while Tertiary amine compounds such as hereinafter referred to as "EDMAB" are generally widely used.

Organic monomers of various chemical structures have been developed for use in photocurable composite resins. 2,2-bis [4- (2-hydroxy-3-methacryloyloxypropoxy) represented by the following general formula (A) as a representative monomer mainly used in dental restorative materials, especially dental fillers, which are currently commercially available. Phenyl] propane (hereinafter referred to as "bis-GMA") or 1,6-bis (2-methacryloyloxyethoxycarbonylamino) -2,2,4-trimethylhexane represented by the following formula (B) Most commonly used because of its excellent physical properties such as high strength after curing.

The main cause of shortening the life span of dental composite resins is polymerization shrinkage during curing reaction. When polymerization shrinkage occurs, adhesion to teeth is weakened, and voids may occur, causing discoloration and tooth decay. The use of monomers of relatively high molecular weight has been reported to be advantageous as one of the methods for minimizing polymerization shrinkage (Dental Materials, Vol. 10, p. 343, 1994 and J. Dent. Res., Vol. 71, p.434). , 1992). However, composite resins using bis-GMA or UDMA have been reported to cause relatively large volumetric shrinkage during photopolymerization (Biomaterials, Vol. 17, p.431, 1994). In addition, bis-GMA has a hydrophilic -OH group in the molecule, and this hydroxyl group plays a role of enhancing affinity between organic resins and inorganic fillers, while having a strong hydrophilic property to absorb moisture. When the composite resin absorbs water, the resin swells, weakening the bonding strength with the filler, the filler particles are separated, and mechanical properties such as strength and abrasion resistance are reduced, and discoloration occurs due to absorption of food, which shortens the life of the composite resin. do. In addition, unreacted monomer molecules that do not participate in polymerization may slowly elute in the oral cavity after the procedure (Journal of Oral Rehabilitation, Vol. 21, p. 453, 1994).

The present inventors have studied an organic monomer which can improve the disadvantages of the conventional dental restoration composite resin, and as a result, has one methacrylate group as compared to bis-GMA, which is a conventional difunctional methacrylate. 1,1,1-tris [4- (2-hydroxy-3-methacryloyloxypropoxy) phenyl] ethane (hereinafter referred to as "THMPE") further having the general formula (D) 1,1,1-tris [4- (2-hydroxy-3-methacryloyloxypropoxy) phenyl] methane (hereinafter referred to as "THMPM") (Dental Materials, Vol. 18, p. 174) , 2002), and the like, have found that trifunctional monomers exhibit lower polymerization shrinkage and solubility compared to bifunctional bis-GMA or UDMA. This is because THMPE and THMPM have a smaller molecular volume, i.e., a higher molecular weight than bis-GMA and UDMA, resulting in less shrinkage during polymerization, and because of the three methacrylate groups per molecule, the probability of participating in the polymerization is greater. The elution tends to be small.

The present inventors have conducted studies to minimize the polymerization shrinkage and water solubility as well as water absorption in the dental restoration composite resin, the volume shrinkage during polymerization is smaller than the conventional monomers, water absorption and water solubility is low It has led to the invention of novel monomers that exhibit excellent photopolymerization and mechanical properties.

The novel organic monomer of the present invention is characterized by increasing the hydrophobicity by substituting a hydrophobic organic group with a hydroxy (-OH) group bound to a trifunctional monomer such as THMPE or THMPM. Increased hydrophobicity of monomer molecules has been reported to reduce water absorption (Dental Materials, vol. 15, p. 166, 1999). The present inventors have found that the substitution of hydroxy groups with hydrophobic groups gives It was confirmed that the water absorption is reduced. It is also known that polymerization shrinkage tends to decrease as the molecular weight of the monomer increases (Dental Materials, vol. 10, p. 343, 1994). In the present invention, the molecular weight of the entire molecule is reduced by substituting a hydroxy group with an acetoxy group. It was possible to decrease the polymerization shrinkage.

On the basis of such experimental facts, the present invention modifies the chemical structure of a conventional monomer, and thus, a novel trifunctional which can reduce the polymerization shrinkage, water absorption and water solubility of the dental restoration composite resin containing the monomer. It has come to invent a meta (a) acrylate ester monomer compound. In addition, the inventors have invented a composite resin composition for dental restorations containing the novel monomers exhibiting excellent properties.

In one aspect, there is provided a novel trifunctional meth (a) acrylate ester monomer which is a component of a dental restoration composite resin.

As another aspect, a trifunctional meth (a) acrylate ester compound is prepared by reacting an anhydride of an acid with a trifunctional meth (a) acrylate compound having three hydroxyl groups or reacting an acid chloride in the presence of a catalyst compound. It provides a method of manufacturing.

In still another aspect, there is provided a photocurable composition for dental restorations containing at least one trifunctional meta (a) acrylate ester monomer, wherein CQ is used as a photopolymerization initiator.

In another aspect, the present invention provides a chemocurable composition for dental restorations, which contains at least one trifunctional meta (a) acrylate ester monomer and is a benzoyl peroxide which is a chemical polymerization initiator instead of the photopolymerization initiator CQ.

The novel monomer compound of the present invention has a structure of formula (1).

In the above formula, R represents hydrogen, methyl, or an aromatic or aliphatic hydrocarbon group having 2 to 20 carbons, R ₁ represents hydrogen or a methyl group, and R ₂ is aromatic or having 2 to 20 carbons or methyl or Aliphatic hydrocarbons.

Among the monomer compounds of Chemical Formula 1, preferred compounds are as shown in the following Chemical Formulas 2 and 3. As can be seen from the formulas (2) and (3), the novel monomer of the present invention has three meta (a) acrylate groups that easily undergo radical polymerization even at room temperature. It cures while forming to exhibit the desired mechanical properties.

1,1,1, -tris [4- (2-acetoxy-3-methacryloyloxypropoxy) phenyl] ethane (hereinafter referred to as "TAMPE") exemplified in the above formula (2) or exemplified in formula (3) The molecular weights of 1,1,1-tris [4- (2-acetoxy-3-methacryloyloxypropoxy) phenyl] methane (hereinafter referred to as “TAMPM”) are 858 / mol and 844 g / mol, respectively, It is larger than conventional bis-GMA (molecular weight 512 g / mol), THMPE (molecular weight 732 g / mol) or THMPM (molecular weight 718 g / mol). Therefore, the composite resin composition containing the monomer of the present invention is expected to exhibit low volume shrinkage in comparison with the conventional composite resin when cured. It is also expected that the -OH group in the molecule is substituted with a hydrophobic acetoxy group to exhibit low water absorption and solubility.

The monomer production method of the present invention is as shown in the following scheme (1). In Scheme (1), R represents hydrogen, methyl or an aromatic or aliphatic hydrocarbon group having 2 to 20 carbons, R ₁ represents hydrogen or methyl group and R ₂ represents methyl or 2 to 20 carbons An aromatic or aliphatic hydrocarbon group is represented. Specifically, an anhydride of the acid represented by the formula (5) or a catalyst is reacted or reacted with the trifunctional meta (a) acrylate compound (Dental Materials, Vol. 18, p. 174, 2002) having three hydroxyl groups. The trifunctional meth (a) acrylate ester compound is synthesized by reacting the chloride derivative of the acid represented by the following formula (6) in the presence. As a catalyst compound, although it is not limited to this, For example, tertiary amine compounds, such as triethylamine, can be used.

Wherein R, R ₁ and R ₂ are as defined above.

The monomer of the present invention can be used as one component of a dental restoration composite resin containing a diluent, an inorganic filler, a polymerization initiator, a reducing agent, a polymerization inhibitor, a dye, and the like. In addition, depending on the composition of the composition may be used in various applications such as composite resin, primer, adhesive for tooth restoration.

In addition, in the composition for dental restoration, the monomer of the present invention may be used alone or in combination with other monomers generally used for curing as needed. Such other monomers are usually mono- or polyfunctional methacrylate monomers, and representative examples thereof include bis-GMA, UDMA, THMPE, THMPM. In addition, when the viscosity of the monomer is high, a diluent component may be added to facilitate the formulation of the composition. Typical examples of the diluent include triethylene glycol dimethacrylate (hereinafter referred to as “TEGDMA”), 2- ( Hydroxyethyl) methacrylate. The monomer of the present invention is used in an amount of 5 to 99% by weight, preferably 10 to 50% by weight, based on 100% by weight of the tooth restorative composition alone or in admixture with other monomers generally used for curing, if necessary.

In addition, when the composition of the present invention is used as a photocurable restorative material, a photopolymerization initiator is added to the composition, and the photopolymerization initiator may be used without particular limitation as a photosensitive compound that reacts to ultraviolet light or visible light. Among them, particularly in dental restorative materials, CQ having visible light reactivity is preferable because of its low biohazard. In addition, these photoinitiators can be used individually or in mixture with other photoinitiators as needed. The content of the photopolymerization initiator may be added at 0.05 to 5% by weight, preferably 0.1 to 2% by weight relative to 100% by weight of the photocurable restoration including the composition of the present invention.

Another major component included in the photocurable composition of the present invention is an amine-based reducing agent used in combination with a photopolymerization initiator to initiate polymerization. In photocuring, a sufficient curing rate cannot be ensured only by the photopolymerization initiator, thereby greatly improving the curing rate by adding an amine-based reducing agent. Representative examples thereof include N, N-dimethylaminoethyl methacrylate (hereinafter referred to as "DMAEMA") and ethyl 4-dimethylaminobenzoate. For example, when CQ and DMAEMA are used as photoinitiator combinations, CQ reacts with visible light to produce hydrogen species from tertiary amine compounds, which produce radical species, which tertiary amine radical species are multifunctional methacrylates. The polymerization of the polymer is initiated to form a dense crosslinked polymer structure. The amount of the amine-based reducing agent may be added in an amount of 0.1 to 5, preferably 0.5 to 2, with respect to the photopolymerization initiator.

When the composition of the present invention is used as a photocurable restorative material, curing does not proceed until the composition is irradiated with visible light with a light irradiator so that the operator can secure sufficient working time. In addition, since the photocurable composition has a single ointment type, no mixing is required during the procedure, so it is convenient to use and there is no fear of inflow of bubbles.

On the other hand, when the composition of the present invention is used as a chemocurable restoration, a chemical polymerization initiator such as benzoyl peroxide or the like is added to the composition instead of the above-described photopolymerization initiator and CQ. However, since the polymerization reaction is initiated at the same time as the chemical polymerization initiator and the reducing compound, the two components must be stored separately and mixed and cured just before the procedure. The content of the chemical polymerization initiator may be added in an amount of 0.05 to 5% by weight, preferably 0.1 to 2% by weight, based on 100% by weight of the chemically curable restoration including the composition of the present invention. The same components as in the case of the photocurable restoration can be used for the chemically curable restoration except for the photopolymerization initiator.

In particular, when the composition of the present invention is used as a filler for dental restoration, an inorganic filler powder having a particle size of 0.02 to 20 microns is added to improve mechanical properties and impart impermeability to X-rays. Examples of the inorganic fillers include quartz, silica, alumina, hydroxyapatite, calcium aluminosilicate, barium aluminosilicate, strontium aluminosilicate and the like. These fillers generally contain from 5 to 85% by weight of the total weight of the composition.

In the composition of the present invention, a pigment for adjusting the color tone of the polymerization inhibitor, the light stabilizer, the oxidizing stabilizer, and the composite resin is added to the composition as appropriate, and when used as a primer or an adhesive, a solvent such as acetone or water is added. Can be added. As a polymerization inhibitor, hydroquinone (hereinafter referred to as "HQ"), hydroquinone monomethyl ether or hydroquinone monoethyl ether, etc., may be present in an amount of 0.1 to 10% by weight of the total weight of the composition. As a light stabilizer, tinuvin is present in an amount of 0.01 to 5% by weight of the total weight of the composition, and as an oxidative stabilizer, iganox and 2,6-dibutylbutyl-4-methylphenol butylate hydroxy toluene (2,6-Di- tert-butyl-4-methyl phenol butylated hydroxytoluene (BHT) in an amount of 0.01 to 5% by weight of the total weight of the composition, and yellow, dark blue, and red iron oxide-based and titanium dioxide inorganic pigments in an amount of 0.005 to 0.5 of the total weight of the composition. It can be added in an amount by weight.

Hereinafter, some exemplary embodiments of the present invention will be described in detail. However, these Examples are only for illustrating an embodiment of the present invention and do not limit the scope of the present invention.

<Example 1>

Synthesis of 1,1,1-tris [4- (2-acetoxy-3-methacryloyloxypropoxy) phenyl] ethane (TAMPE)

Of 1,1,1-tris [4- (2-hydroxy-3-methacryloyloxypropoxy) phenyl] ethane (THMPE) (21.53 g, 29.4 mmol), acetic anhydride (134.7 g, 1.32 mol) The mixture was reacted at 65 ° C for 24 hours. Dichloromethane was added to the above solution to complete the reaction, and the solution was washed sequentially with 0.5 molar hydrochloric acid solution, 0.1 molar sodium hydroxide aqueous solution, and brine. Anhydrous magnesium sulfate was added to the obtained solution to remove water, and the solvent was removed under reduced pressure to thereby remove 1,1,1-tris [4- (2-acetoxy-3-methacryloyloxypropoxy) phenyl] ethane (TAMPE). Was obtained as a pale green liquid (22.5 g, yield 89%). The frequency and nuclear magnetic resonance spectroscopy of the final compound TAMPE in the infrared region were as follows.

IR (neat): ν (cm ⁻¹ ) 3455, 2927, 1715, 1633, 1607.

¹ H NMR (CDCl ³ , 300 MHz): δ (ppm) 1.94 (s, 9H), 2.07 (s, 3H), 2.10 (s, 9H), 4.1-4.48 (m, 12H), 5.43 (m, 3H) , 5.59 (s, 3H), 6.11 (S, 3H), 6.78-6.99 (dd, 12H).

The intermediate compound 1,1,1-tris [4- (2-hydroxy-3-methacryloyloxypropoxy) phenyl] ethane (THMPE) (21.53 g, 29.4 mmol), anhydrous trimethylamine (8.93 g , 88.2 mmol) was dissolved in anhydrous tetrahydrofuran (50 ml). After cooling the above solution to 4 ℃ acetyl chloride (7.6g, 97mmol) was slowly added dropwise and the mixture was reacted at room temperature for 12 hours. Dichloromethane was added to the above solution to complete the reaction, and the solution was washed sequentially with 0.5 molar hydrochloric acid solution, 0.1 molar sodium hydroxide aqueous solution, and brine. Anhydrous magnesium sulfate was added to the obtained solution to remove water, and the solvent was removed under reduced pressure to thereby remove 1,1,1-tris [4- (2-acetoxy-3-methacryloyloxypropoxy) phenyl] ethane (TAMPE). Was obtained as a pale green liquid (21.5 g, yield 85%). The frequency and nuclear magnetic resonance spectroscopy of the final compound TAMPE in the infrared region were as follows.

IR (neat): ν (cm ⁻¹ ) 3455, 2927, 1715, 1633, 1607.

¹ H NMR (CDCl 3, 300 MHz): δ (ppm) 1.94 (s, 9H), 2.07 (s, 3H), 2.10 (s, 9H), 4.1-4.48 (m, 12H), 5.43 (m, 3H), 5.59 (s, 3 H), 6.11 (S, 3 H), 6.78-6.99 (dd, 12 H).

Example 2

Synthesis of 1,1,1-tris [4- (2-acetoxy-3-methacryloyloxypropoxy) phenyl] methane (TAMPM)

A mixture of 1,1,1-tris [4- (2-hydroxy-3-methacryloyloxypropoxy) phenyl] methane (THMPM) 21.11 g, 29.4 mmol), acetic anhydride (34.7 g, 1.32 mol) Was reacted at 65 ° C for 24 hours. Dichloromethane was added to the above solution to complete the reaction, and the solution was washed sequentially with 0.5 molar hydrochloric acid solution, 0.1 molar sodium hydroxide aqueous solution, and brine. Anhydrous magnesium sulfate was added to the obtained solution to remove water, and the solvent was removed under reduced pressure to thereby remove 1,1,1-tris [4- (2-acetoxy-3-methacryloyloxypropoxy) phenyl] ethane (TAMPM). Was obtained as a pale green liquid (21.5 g, yield 85%). The frequency and nuclear magnetic resonance spectroscopy of the final compound TAMPM in the infrared region were as follows.

IR (neat): ν (cm ⁻¹ ) 3455, 2927, 1715, 1633, 1607.

¹ H NMR (CDCl 3, 300 MHz): δ (ppm) 1.94 (s, 9H), 2.07 (s, 3H), 2.10 (s, 9H), 4.1-4.48 (m, 12H), 5.43 (m, 3H), 5.59 (s, 3 H), 6.11 (s, 3 H), 6.78-6.99 (dd, 12 H).

The intermediate compound, 1,1,1-tris [4- (2-hydroxy-3-methacryloyloxypropoxy) phenyl] methane (THMPM) (21.11 g, 29.4 mmol), anhydrous trimethylamine (8.93 g , 88.2 mmol) was dissolved in tetrahydrofuran (50 ml). After cooling the above solution to 4 ℃ acetyl chloride (7.6g, 97mmol) was slowly added dropwise and the mixture was reacted at room temperature for 12 hours. Dichloromethane was added to the above solution to complete the reaction, and the solution was washed sequentially with 0.5 molar hydrochloric acid, 0.1 molar sodium hydroxide and brine. Anhydrous magnesium sulfate was added to the resulting solution to remove water, and the solvent was removed under reduced pressure to thereby remove 1,1,1-tris [4- (2-acetoxy-3-methacryloyloxypropoxy) phenyl] methane (TAMPM). Was obtained as a pale green liquid (21.1 G, yield 85%). Nuclear magnetic resonance spectroscopy of the final compound TAMPM was as follows.

¹ H NMR (CDCl 3, 300 MHz): δ (ppm) 1.93 (s, 9H), 2.08 (s, 9H), 5.42 (s, 3H), 5.62 (s, 3H), 6.10 (s, 3H), 6.76- 7.00 (m, 12 H).

<Example 3>

Measurement of Photopolymerization Conversion Rate

The composition prepared by mixing the novel monomer, TEGDMA, CQ, DMAEMA in a ratio of 60: 40: 1: 1 was applied to a NaCl substrate and polymerized by irradiating visible light of 420-500nm. Polymerization conversion was measured by transmission method by KBr (pellet) using infrared absorption spectroscopy, based on the absorption band area of 1609 cm ^-1 due to aromatics of meta (a) acrylate carbon-carbon double bond It was calculated by measuring the area reduction of the absorption band (1633 cm ^-1 ). The formula used for this calculation is as following formula (1). The conversion measurement was repeated three times for each sample and the average value was taken.

As a result of the polymerization conversion measurement, the new monomers of the present invention, TAMPE and TAMPM, were almost completely polymerized by irradiation for 40 seconds, and showed conversion of 63/4% and 60.5%, respectively, for 40 seconds. Values similar to 60.6%, 60.0%, and 57.4% of -GMA, THMPE, and THMPM were shown. Therefore, the monomer of the present invention was found to have excellent radical polymerization similar to existing monomers which are currently commonly used in dental composite resins.

Example 4

Polymerization Shrinkage Measurement

A polymerization shrinkage measuring device having a 10 μl syringe attached to the inlet of the density measuring candle (25 ml) was manufactured and measured using a water substitution method using the same. A composition containing monomers, TEGDMA, CQ, and DMAEMA in a ratio of 60: 40: 1: 1 was placed in a 25 × 2 × 2 mm Teflon mold, and polymerized by irradiation with light for 60 seconds from the top and bottom of the mold. The scale of the syringe that changed with the progress of polymerization was read, and this value was divided by the original volume to calculate the polymerization shrinkage. The density before and after polymerization was measured, and the polymerization shrinkage percentage (%) was calculated by the following equation (2). The average value was repeated three times for each sample. Shrinkage measurement experiments were performed in a thermostat to minimize the effect of temperature on volume.

As a result of measuring the polymerization shrinkage rate, the new monomers of TAMPE and TAMPM showed 5.48% and 5.54% shrinkage, respectively, and the same experiment was performed on the existing monomers bis-GMA, THMPE and THMPM for comparison. The results showed 6.43%, 5.63% and 5.79%, respectively. From these results, when the monomer of the present invention is used as the monomer of the tooth restorative composite resin, the adhesiveness with the tooth is improved by reducing the polymerization shrinkage rate, the color stability is improved, and the secondary cavities are prevented, compared to the conventional bis-GMA composite resin. It is expected to represent the characteristics of.

Example 5

Water Absorption and Water Solubility Measurements

A disk-shaped stainless steel mold having a thickness of 1.0 mm and a diameter of 15 mm was filled with a composition containing monomer, TEGMDA, barium aluminosilicate powder, CQ, and DMAEMA in a ratio of 15: 10: 75: 0.18: 0.36, and 4 on one side. Each part was irradiated for 20 seconds each to photopolymerize for 160 seconds to produce a specimen. The specimen was removed from the mold and stored in a dryer containing silica gel dried at 130 ° C. for 5 hours and stored at 37 ° C. for 24 hours. After storage for 1 hour again, the weight of the specimen was measured (m ₁ ). At this time, m ₁ was measured several times at intervals of time to determine the weight when the constant weight is less than 0.2 mg.

After storing the above specimen in distilled water at 37 ° C. for 7 days, the surface water was removed with cellulose tissue, dried in air for 1 hour, and weighed (m ₂ ). Water absorption after 7 days from Equation (3) The figure was calculated. After drying for 24 hours in a dryer at 37 ℃ again, the weight is measured, repeated measurement every 24 hours when the weight change does not exceed 0.2 mg as the final dry weight (m ₃ ), the following equation ( The solubility was calculated from 4).

In the above formula

S; Cross section

m ₁ ; Weight of specimen measured before immersion.

m ₂ ; Weight of specimen after immersion.

m ₃ ; Weight of the specimen remeasured.

As a result of water absorption measurement, the composite resin containing the monomer of the present invention showed water absorption as low as half as compared with the bis-GMA, THMPE and THMPM-containing composite resin. More specifically, the new monomers of the present invention, TAMPE and TAMPM, respectively, showed 9.92 and 11.2 µg / mm ³ , and the same experiment was performed on the existing monomers bis-GMA, THMPE, and THMPM for comparison. The results showed 19.83, 18.65, and 20.59 µg / mm ³ , respectively. Therefore, the composite resin of the present invention is expected to have an improved lifetime compared to the conventional composite resin. In addition, the water solubility measurement resulted in a very low solubility in the composition containing THMPE and THMPM more than half, compared to the composition of the same composition containing bis-GMA. More specifically, the new monomers TAMPE and TAMPM of the present invention showed 0.89 and 0.98 µg / mm ³ , respectively, and the same experiment was performed on the existing monomers bis-GMA, THMPE, and THMPM for comparison. As a result, 2.10, 1.27, 1.51 microgram / mm <^3> was shown respectively. Therefore, the composite resin of the present invention is expected to exhibit improved biocompatibility compared to the conventional composite resin.

<Example 6>

3-point flexural strength measurement

A composition containing monomer, TEGMDA, barium aluminosilicate powder, CQ, and DMAEMA in a ratio of 15: 10: 75: 0.18: 0.36 was filled into a 25mm × 2mm × 2mm Teflon mold, covered with a transparent vinyl sheet, and then clamped. A specimen was prepared by irradiating 420-500 nm visible light for 60 seconds while applying pressure using a clamp. The specimen was soaked in distilled water maintained at 37 ° C for 24 hours, then removed to remove moisture from the surface and fractured at a cross-head speed of 0.75 ± 0.25mm / min with an universal tester (Instron). Force was recorded until the highest load on the specimen was recorded. The flexural strength was obtained in MPa units from the following Equation (5), and the average value was repeated five times for each sample.

σ = 3F / 2bh ^ 2

In the above formula

F: highest load on the specimen

I: Distance between supports measured with 0.01mm accuracy

b: width of the specimen measured before the test (17 mm)

h: thickness of the specimen measured immediately before the test

After photocuring the composite resin composition of the present invention, the three-point flexural strength, which is a representative item in the evaluation of physical properties of the dental restorative material, was measured. As a result, the bis-GMA composite resin of the same composition Similar mechanical properties were shown. More specifically, the new monomers TAMPE and TAMPM of the present invention showed 99.8 and 102.2 MPa, respectively, and for comparison, the same experiment was performed on the existing monomers bis-GMA, THMPE, and THMPM, respectively. 103.3, 97.9 and 89.6 MPa.

As can be seen from the above test results, it was confirmed that the composite resin composition of the present invention is a tooth restorative material which improves the volume shrinkage problem, water absorption and water solubility during polymerization, which are typical disadvantages of the conventional bis-GMA composite resin. More specifically, it was confirmed that the composite resin composition of the present invention is a dental restoration composite resin exhibiting high polymerizability, low polymerization shrinkage rate, low water absorption, low water solubility and excellent mechanical properties.

The novel trifunctional meta (a) acrylate ester monomer compounds of the invention are useful as constituents of dental restorative compositions.

Claims (13)

Trifunctional meta (a) acrylate ester monomer represented by Formula 1: Wherein R represents hydrogen, methyl or an aromatic or aliphatic hydrocarbon group having 2 to 20 carbons, R ₁ represents hydrogen or a methyl group and R ₂ represents an aromatic or aliphatic carbonization having 2 to 20 carbon atoms or methyl Hydrogen group is represented. The monomer of claim 1, wherein R is hydrogen or methyl, R ₁ is methyl and R ₂ is methyl. A method of preparing a trifunctional meta (a) acrylate ester monomer represented by the following Chemical Formula 1, characterized by reacting a compound of Chemical Formula 4 with a compound of Chemical Formula 5: Wherein R represents hydrogen, methyl or an aromatic or aliphatic hydrocarbon group having 2 to 20 carbons, R ₁ represents hydrogen or a methyl group and R ₂ represents an aromatic or aliphatic carbonization having 2 to 20 carbon atoms or methyl Hydrogen group is represented. A method for preparing a trifunctional meta (a) acrylate ester monomer represented by the following Chemical Formula 1, characterized in that the compound of Chemical Formula 4 is reacted in the presence of the compound of Chemical Formula 6 with a catalyst compound: Wherein R represents hydrogen, methyl or an aromatic or aliphatic hydrocarbon group having 2 to 20 carbons, R ₁ represents hydrogen or a methyl group and R ₂ represents an aromatic or aliphatic carbonization having 2 to 20 carbon atoms or methyl Hydrogen group is represented. The method of claim 3 or 4, wherein R is hydrogen or methyl, R ₁ is methyl and R ₂ is methyl. The process according to claim 3, wherein the anhydride of the acid of formula 5 is reacted or the acid chloride is reacted in the presence of a catalyst compound. The process of claim 4 wherein the catalyst compound is triethylamine. A photocurable composition for dental restoration comprising at least one trifunctional meta (a) acrylate ester monomer represented by the following formula (1) and comprising a photopolymerization initiator. Wherein R represents hydrogen, methyl or aromatic or aliphatic hydrocarbon group having 2 to 20 carbon atoms, R ₁ represents hydrogen or methyl group and R ₂ represents aromatic or aliphatic hydrocarbon having 2 to 20 carbon atoms or methyl Group. 9. The photocurable composition for dental restoration according to claim 8, wherein the photopolymerization initiator is camphorquinone. 9. The photocurable composition for dental restoration of claim 8 wherein R is hydrogen or methyl, R ₁ is methyl and R ₂ is methyl. A chemocurable composition for dental restoration comprising at least one trifunctional meta (a) acrylate ester monomer represented by the following formula (1), and adding a chemical polymerization initiator to the composition. Wherein R represents hydrogen, methyl or aromatic or aliphatic hydrocarbon group having 2 to 20 carbon atoms, R ₁ represents hydrogen or methyl group and R ₂ represents aromatic or aliphatic hydrocarbon having 2 to 20 carbon atoms or methyl Group. 12. A chemocurable composition for dental restoration according to claim 11 wherein the chemical polymerization initiator is benzoyl peroxide. 12. A dental restorative chemocurable composition according to claim 11, wherein R is hydrogen or methyl, R ₁ is methyl and R ₂ is methyl.