JP2002104914A - Method for producing dental material and prosthetic material for dental use - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a dental material having simple impregnation operability, high adhesion to fiber and high mechanical strength, and to provide a prosthetic material for dental use having good handleability and high mechanical strength and fatigue durability. SOLUTION: This method for producing a dental material comprises preparing in advance a composition mainly comprising (a) a polymerizable monomer, (b) a fiber, (c) a solvent and (d) a polymerization initiator followed by removing the solvent (c) from the composition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a dental material and a dental prosthesis. More specifically, a polymerizable composition comprising a polymerizable monomer (a), a fiber (b), a solvent (c) and a polymerization initiator (d) is prepared in advance, and thereafter,
The present invention relates to a method for producing a dental material for removing a solvent (c) from the composition.

[0002]

2. Description of the Related Art A dental composition comprising a polymerizable monomer and a filler is widely used clinically as a so-called dental composite resin. Due to its simple operability, aesthetics, low production cost, and the like, the use of dental composite resins is expanding to dental filling materials for dental caries cavities as well as crown materials such as inlays, crowns, and bridges. However, even with a dental composite resin that has improved mechanical strength by incorporating a fine filler, there is a limit to the improvement in strength, and it is necessary to replace all cases where metal is used in dental restoration with composite resin. Not reached.

Hitherto, in order to dramatically increase the mechanical strength of a composite resin, a fiber-reinforced composite material in which fibers are mixed with a polymerizable dental composition has been studied. For example, JP-A-57-87302, JP-A-61-15
JP-A No. 2607, JP-A-2-38402, JP-A-4-504874, JP-A-6-152731 and JP-A-7-138120 disclose inorganic or metal short fibers (whiskers) as monomers. A method for obtaining a composite resin having excellent mechanical strength by mixing with a filler, a polymerization initiator and the like is disclosed.

However, the method of producing a composite material described in these publications is a method of producing by simply mixing or adding a monomer, a fiber, a filler, and the like. When dispersed and mixed, the viscosity of the admixture increases significantly as the fiber content increases,
Problems such as breakage of fibers during mixing occur.

On the other hand, attempts have been made to obtain a dental composite material having further excellent mechanical strength by using a long fiber, a sheet-like fiber, a woven fabric or the like as a fiber material. For example, Japanese Patent Publication No. 3-503848 discloses a method of manufacturing a fiber-reinforced passive dental apparatus in two steps. According to the above publication, first, a fiber-reinforced composite material is produced, and then a dental prosthesis is formed. The composite material has a polymer matrix and a fiber component which are completely adhered to each other, which is observed under a microscope. And that it can be confirmed by the elastic modulus value.

However, this publication does not disclose any specific method for achieving such adhesion, but discloses a method of simply impregnating a polymer matrix and fibers. Not just. For example, when using a converging yarn of a long fiber, in addition to the above-mentioned adhesion between the matrix and the fiber, it is important to increase the convergence density in order to exert a large reinforcing effect, but a conventionally known impregnation method is used. Then, when a monomer having a certain high viscosity is used as a matrix, it is difficult to remove bubbles and increase the convergence density. On the other hand, when a liquid monomer is used, the convergence density can be increased, but there is a drawback such as loosening over time.

Japanese Patent Application Laid-Open No. 2-84752 discloses a composite material in which a sheet-like fiber is impregnated with a monomer or oligomer resin. Specifically, when processing into a sheet, the resin is impregnated into the fiber by covering with a film and pressing with a roller. However, in this production method, when the viscosity of the resin is low, the resin is easily separated from the fibers when pressing with a roller, and when the viscosity of the resin is high, a large amount of time is required for the resin to penetrate into the fibers. In addition, workability is not always good, for example, resin adheres to the film.

Japanese Patent Publication No. 5-503869 discloses a dental prosthesis in which a polyethylene or aramid woven fabric is coated with a resin. Then, as a coating method, in addition to a known method of impregnating the fiber with a liquid resin, first, the wettability of the surface of the fiber is increased with a thinner or a liquid monomer so that the liquid resin is not absorbed into the fiber. Two-step methods such as impregnation with a resin are also disclosed. However, in general, it is difficult to impregnate the liquid resin into the fiber by these methods using a resin having a relatively high viscosity that gives a high-strength cured product or a molded product, and because of a two-stage impregnation process. However, work efficiency is not always good.

JP-A-10-14943 and JP-A-5-503869 disclose a reinforcing material using plasma-treated polyethylene fiber and resin. Products manufactured by the former are connected by CONN.
ECT) under the trade name Carr (Corpora)
), and the latter is RIBBO
ND) under the trade name Ribbbond, In
c. ). However, in these products, the fiber and the resin are not previously integrated, and the fiber must be impregnated with the resin by the user. Furthermore, in order to prevent contamination of the fiber surface, complicated work such as wearing gloves and handling fibers is required, and there is a problem that inappropriate impregnation lowers mechanical properties.

Japanese Patent Publication No. 9-507238 discloses a dental composition containing a web, a woven fabric or a filament, a UV- or light-permeable container containing the composition, and a tool for polymerizing the composition. It has been disclosed. However, with respect to the method of making the dental composition,
It merely shows a conventional method of impregnating a textile or the like with a hardenable and / or polymerizable dental composition.

Japanese Patent Laid-Open Publication No. Hei 10-305045 discloses a method for producing a fiber-reinforced composite. The fibrous material impregnated in the organic matrix obtained in this way is sold under the trade name VECTRIS under the trade name of IVOCLAR, AKTIENGES.
ELSCHAFT). This method
This is a so-called press molding method using a mold in which an organic matrix and the fiber material impregnated in the organic matrix are arranged in a cavity of a mold, and molded through a membrane by a pressurizing device. However, there is no specific disclosure of a method for producing the fiber material. Further, in order to obtain the fiber-reinforced composite using the fiber material, a dedicated pressurizing device is required, so that the manufacturing cost is increased.

[0012]

As described above, the application of a composite material comprising an organic matrix (resin and / or polymerizable monomer) and fibers to dental materials has been actively attempted in part. However, according to the conventional manufacturing method, it is difficult to disperse or impregnate the fibers in the organic matrix. In particular, it is difficult to uniformly disperse the fibers due to the inclusion of bubbles.

Accordingly, it is an object of the present invention to provide a method for producing a dental material having excellent adhesion to fibers and mechanical strength, and excellent handling properties. Another object of the present invention is to provide a dental prosthesis manufactured using the above-mentioned dental material and having excellent mechanical strength and fatigue durability.

[0014]

Means for Solving the Problems The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, they have surprisingly found that a desired fiber composite material can be obtained by the following simple operation. Invented the invention. That is, the present invention relates to a method for producing a dental material containing fibers, wherein a polymerizable monomer (a), a fiber (b), a solvent (c) and a polymerization initiator (d) are prepared in advance.
A method for producing a dental material, comprising: preparing a polymerizable composition comprising: and then removing the solvent (c) from the composition. Another aspect of the present invention is a dental prosthesis containing a dental material obtained by the manufacturing method.

The polymerizable monomer (a) used in the present invention includes, for example, α-cyanoacrylic acid, (meth) acrylic acid, α-halogenated acrylic acid, crotonic acid, cinnamic acid, maleic acid, itacone Esters such as acids, (meth)
Examples thereof include (meth) acrylamides such as acrylamide or (meth) acrylamide derivatives, vinyl esters, vinyl ethers, mono-N-vinyl derivatives, and styrene derivatives. Among them, (meth) acrylic acid esters and (meth) acrylamides are preferable in terms of good polymerizability. Examples of such a polymerizable monomer are shown below.

(A) Monofunctional monomer: Monofunctional monomers having one polymerizable group include methyl (meth) acrylate, iso-butyl (meth) acrylate, benzyl (meth) acrylate, lauryl (Meth) acrylate, 2- (N, N-dimethylamino) ethyl (meth) acrylate, 2,3-dibromopropyl (meth) acrylate, 3- (meth) acryloyloxypropyltrimethoxysilane, 2-hydroxyethyl (meth ) Acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 6-
Hydroxyhexyl (meth) acrylate, 10-hydroxydecyl (meth) acrylate, propylene glycol mono (meth) acrylate, glycerin mono (meth) acrylate, erythritol mono (meth) acrylate, N-methylol (meth) acrylamide, N-
Hydroxyethyl (meth) acrylamide, N, N-
(Dihydroxyethyl) (meth) acrylamide, (meth) acryloyloxidedecylpyridinium bromide and the like.

(B) Bifunctional monomer: Examples of the bifunctional monomer having two polymerizable groups include ethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, and propylene glycol di ( (Meth) acrylate, neopentyl glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1,10-decanediol di (meth) acrylate, bisphenol A diglycidyl (meth) acrylate (commonly called Bis-GMA) 2-hydroxy-3- (meth) acryloyloxypropyl (meth) acrylate, 2,2-bis [4- (meth) acryloyloxypolyethoxyphenyl] propane, 1,2-bis [3-
(Meth) acryloyloxy-2-hydroxypropoxy] ethane, 1,2-bis [3- (meth) acryloyloxy-2-hydroxypropyloxy] triethylene glycol, 1,2-bis [3- (meth) acryloyloxy -2-hydroxypropyloxy] glycerin,
Pentaerythritol di (meth) acrylate, 2,
2,4-trimethylhexamethylenebis (2-carbamoyloxyethyl) di (meth) acrylate (commonly known as UD
MA) and the like.

(C) Trifunctional or higher monomers: Trifunctional or higher monomers having three or more polymerizable groups include trimethylolpropane tri (meth) acrylate and trimethylol ethane tri (meth) Acrylate, tetramethylolmethanetri (meth) acrylate, tetramethylolmethanetetra (meth) acrylate, pentaerythritoltetra (meth) acrylate, N, N ′-(2,
2,4-trimethylhexamethylene) bis [2- (aminocarboxy) propane-1,3-diol] tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, and the like.

In addition, bisurethane acrylate methacrylate described in JP-A-5-262615 and phosphoric acid groups, carboxyl groups, pyrophosphoric acid groups, sulfonic acid groups and the like commonly used in dental compositions are provided. Polymerizable compositions can also be used.

The above polymerizable monomers may be used alone or in combination of two or more. In addition to these polymerizable monomers, a polymer such as polymethyl (meth) acrylate or polyurethane may be added for the purpose of improving the toughness, impact strength and operability of the dental material.

The fibers (b) used in the present invention include rovings in which single fibers having a diameter of about 1 to 100 μm converge in units of tens to hundreds of thousands, short fibers, strands, and twists obtained by cutting them short. In addition to the yarns coated with the fibers, various fiber shapes such as woven or knitted fabrics, mixed fibers, mats, cloths, ribbons, tapes, ropes and straws can be used. Above all, it is preferable to use a roving of converging filaments of long fibers or a knitted or woven fabric, since a high reinforcing effect is exhibited.

Particularly, when a dental material is produced using a converging yarn (roving) in which thousands to tens of thousands of long fibers having a fiber diameter of 8 to 30 μm are combined, a dental prosthesis is formed. In this case, the mechanical reinforcing effect is high, which is preferable.

The fibers (b) include glass fibers based on silica such as E glass and S glass, inorganic fibers such as alumina fibers and ceramics, and further include polyethylene fibers, polyester fibers, vinylon fibers, and aromatic fibers. Various organic fibers such as polyamide fibers (commonly known as Kevlar), carbon fibers, and aromatic polyester fibers (commonly known as Vectran) may be used alone or in combination of two or more. Glass fibers that are relatively easily available as E glass and S glass are preferable fibers in terms of cost and mechanical strength.

In order to further improve the adhesion between the glass fiber and a resin such as a polymerizable monomer, the surface of the glass fiber is treated with a known surface treating agent such as a silane coupling agent. Processing is preferred. This type of surface treatment not only contributes to an increase in mechanical strength as generally known, but also increases the rate of impregnation of a monomer containing a solvent in the step of impregnating a solution, thereby increasing the manufacturing process surface. It also brings benefits.

The amount of the fiber (b) is from 20 to 800 parts by weight, preferably from 50 to 300 parts by weight, based on 100 parts by weight of the polymerizable monomer (a). This relates to the balance between the amount of the polymerizable monomer required to adjust to the fiber and the high mechanical strength. That is, if there are too many fibers with respect to the polymerizable monomer, the polymerizable monomer cannot be evenly mixed with the fibers, and voids are easily generated inside the composite material. On the other hand, if the amount of the polymerizable monomer is too large, the fiber content in the composite material becomes relatively low, and high mechanical strength may not be obtained.

The solvent (c) used in the present invention includes:
Those having a relatively low boiling point at normal pressure, specifically having a boiling point of 30
C. to 200.degree. C. are preferred from the viewpoint of workability and ease of removal in a subsequent step. Examples of such a solvent include hydrocarbons such as hexane, heptane, benzene, toluene and styrene; alcohols such as methanol, ethanol, propanol and glycerin; halogenated hydrocarbons such as methyl chloride, dichloromethane and chloroform; and diethyl ether. , Diisopropyl ether, ethers such as acetal, ketones such as acetone and methyl ethyl ketone, methyl acetate, ethyl acetate,
Esters such as methyl methacrylate can be mentioned. These solvents can be used alone or in combination of two or more as necessary.

The solvent (c) is a polymerizable monomer (a) 100
It is used in an amount of 30 to 300 parts by weight, more preferably 70 to 150 parts by weight based on parts by weight. The viscosity of the composition of the polymerizable monomer containing the polymerization initiator described below and the solvent is important in the production method of the present invention, and is 20% at room temperature.
It is desirable to adjust the viscosity so as to be 0 cps or less, more preferably 40 cps or less. 200 cp viscosity
When the value is s or more, it may be difficult to rapidly impregnate the fiber with the composition.

As the polymerization initiator (d) used in the present invention, known polymerization initiators such as a photopolymerization initiator and a heat polymerization initiator can be used without any limitation. Particularly, in the embodiment of the present invention, a photopolymerization initiator is preferable. As such a photopolymerization initiator, for example, a combination of a photosensitizer and a photopolymerization accelerator such as α-diketone represented by camphorquinone can be used. N, N
-Dimethylaminoethyl methacrylate, tertiary amines such as N, N-dimethylaminobenzoic acid alkyl ester, barbituric acids such as 1-benzyl-5-phenylbarbituric acid, organic peroxides such as benzoyl peroxide, mercapto Mercaptans such as benzoxazole; azo compounds such as azobisisobutyronitrile;

Further, ultraviolet polymerization initiators such as benzyldimethyl ketal and benzoin isopropyl ether;
Acylphosphine oxide-based photopolymerization initiators can also be used. Such acyl phosphine oxides include, for example, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2,6-dimethoxybenzoyldiphenylphosphine oxide, 2,3,5
6-tetramethylbenzoyldiphenylphosphine oxide, benzoyldi- (2,6-dimethylphenyl)
Examples thereof include phosphonate and 2,4,6-trimethylbenzoylethoxyphenylphosphine oxide. These acylphosphine oxide-based photopolymerization initiators may be used alone or in combination with a reducing agent such as various amines, aldehydes or mercaptans.

Examples of the heat polymerization type initiator include peroxides such as bezoyl peroxide, ketone peroxide and peroxyketal, and azo compounds represented by 2,2-azobisisobutyronitrile. Agents.

The amount of the polymerization initiator described above is in the range of 0.01 to 5 parts by weight, more preferably 0.05 to 3 parts by weight, based on 100 parts by weight of the polymerizable monomer (a). It is. In addition to such a polymerization initiator, if necessary, an ultraviolet absorber, an antioxidant, a polymerization inhibitor and the like may be added.

The dental material of the present invention may further contain a filler (e). There is no particular restriction on the order of preparing the polymerizable composition, but the polymerizable monomer (a)
A composition consisting of the solvent (c), the polymerization initiator (d) and the filler (e) may be prepared and impregnated with the fiber (b).

Examples of the filler include various kinds of glass such as silicon dioxide (quartz, quartz glass, silica, etc.), alumina,
It contains silicon and boron and / or aluminum together with various heavy metals such as lanthanum, barium, and strontium. Various ceramics, kaolin, clay minerals (such as montmorillonite), mica, calcium fluoride, calcium phosphate, barium sulfate, Known materials such as zirconium oxide and titanium oxide can be used. Various pigments may be added for the purpose of coloring or the like.

The shape of the filler is not particularly limited, such as a crushed shape, a spherical shape, and an irregular shape.
It is in the range of μm. Furthermore, for these fillers,
Depending on the purpose, surface treatment may be performed with a known surface treatment agent such as a silane coupling agent or a titanate coupling agent.

More preferable fillers used in the present invention are ultradispersible ultrafine particles having a particle size of 0.005 to 0.1 μm, and silica or alumina is particularly preferable. The reason for this is that the impregnation property of the fiber is not impaired, and higher adhesion to the fiber, improvement in mechanical strength, and modification of the surface properties of the final product can be achieved at the same time. In addition, when the finished material is later prepared with a dental prosthesis such as a bridge or a crown, it is important from the viewpoint of technical operability that the material has appropriate adhesiveness and adhesion to a plaster model. The addition of various ultrafine fillers is useful for maintaining such desirable properties over a long period of time. The filler (e) is used in an amount of 5 to 150 parts by weight, preferably 10 to 50 parts by weight, based on 100 parts by weight of the polymerizable monomer (a).
It is blended so as to be parts by weight.

Next, a method for producing the dental material of the present invention will be described. In the present invention, first, the polymerizable monomer (a), the solvent (c), and the polymerization initiator (d) are dissolved in advance,
If necessary, the composition containing the filler (e) is impregnated with the fiber (b) to prepare a polymerizable composition. Thereafter, the solvent (c) is removed from the polymerizable composition to obtain a dental composition. Manufacturing materials As described above, in preparing the composition, the order of adding each component is not limited. However, it is preferable to prepare the composition according to the above-described order from the viewpoint of workability.

As a method for producing a dental material comprising a polymerizable resin and a fiber, a method has heretofore been employed in which a liquid polymerizable resin is impregnated with a fiber, the fiber is mixed with the resin, and then an excess liquid resin is formed. However, in this method, it takes time to blend the fiber and the resin, or a special mechanical device may be required. In addition, in order to sufficiently impregnate the fiber with the resin, it is necessary to use the resin in a larger amount than necessary, and it is necessary to remove the excess resin in a later step. Furthermore, if the viscosity of the polymerizable resin to be impregnated is high, it is practically difficult to impregnate the fiber with the resin.

The method for producing a dental material according to the present invention solves such a problem at once, and even if a polymerizable resin having any viscosity is used by adding a solvent (c), the resin can be easily converted into a fiber material. It is possible to impregnate, by removing the solvent after preparing the polymerizable composition,
A dental material having excellent adhesion between the polymerizable monomer and the fiber can be obtained. That is, since the resin diluted with the solvent has excellent fluidity, it can easily penetrate into the gaps between the fibers, and at this stage, the fibers and the resin can be sufficiently blended in a short time.
Thereafter, the desired dental material can be obtained by removing the solvent. However, this series of operations is extremely simple, and the incorporation of air bubbles and the generation of voids can be significantly suppressed. Therefore, the obtained dental material has better mechanical strength than the dental material obtained by the conventional method.

To remove the solvent (c) from the polymerizable composition containing the polymerizable monomer (a), the solvent (c) and the polymerization initiator (d) as main components, for example, the polymerizable composition The simplest method is to place the product in a container of a predetermined shape and leave it to stand, and then leave it as it is at room temperature until the solvent evaporates.However, there is also a method of heating or putting in a desiccator to promote the evaporation of the solvent under reduced pressure. Adopted. The solvent (c) needs to be removed to a level that does not practically affect the mechanical strength of the intended dental material, and usually about 0. 0 to the polymerizable composition.
It is preferable to remove it to 3% by weight or less. The content of the solvent in the polymerizable composition can be easily confirmed by analysis means such as gas chromatography.

In the present invention, the polymerizable composition can easily contain a large amount of the filler (e). It is well-known that a filler is added to a dental polymerizable composition to adjust the viscosity of the composition, modify the surface properties, improve mechanical strength, etc., using a conventional method, When obtaining a composition containing a filler in addition to the fiber and the polymerizable monomer, it has been difficult. That is, when the filler is mixed with the polymerizable monomer, the viscosity rise is remarkable, and it is often difficult to impregnate the monomer into the fiber bundle, and it is extremely difficult to uniformly disperse the filler. Met. However, according to the production method of the present invention, even a dental composition to which a filler is added can be a composition in which fine fillers are uniformly dispersed.

[0041] The dental material of the present invention can be formed into a dental prosthesis. Dental prostheses include crowns, inlays, onlays, bridges, implant superstructures,
Examples include artificial teeth, dentures, and denture bases. However, the dental material of the present invention has excellent mechanical strength and fatigue durability. Can be. The dental material obtained by the production method of the present invention may be supplied to a user (a dentist or a technician) as a product before polymerization, and may be subjected to polymerization curing and molding on the user side, or may be subjected to polymerization curing. After that, it may be formed into an appropriate shape and supplied to the user. Hereinafter, the present invention will be described specifically with reference to Examples, but the present invention is not limited to these Examples.

[0042]

EXAMPLES Example 1 Bisphenol A diglycidyl (meth) acrylate (hereinafter Bis-GMA) 90 was used as the polymerizable monomer (a).
Parts by weight, 10 parts by weight of triethylene glycol di (meth) acrylate (hereinafter, 3G) as a diluent monomer, 110 parts by weight of absolute ethanol as a solvent (c), and dl-camphorquinone (hereinafter, CQ) 0 as a polymerization initiator (d) .
2 parts by weight and 0.1 part by weight of ethyl 4-N, N-dimethylaminobenzoate (hereinafter referred to as DMA) were mixed and dissolved to prepare a composition for impregnation. The viscosity of this impregnating composition is 25 ° C.
Was about 20 cps.

A single fiber having a fiber diameter of 11 μm is about 10,000
This converged E glass fiber bundle yarn (trade name: glass fiber roving, code. RS240PU-53)
7. Nitto Boseki, glass fiber surface is treated with a silane coupling agent) Approx. 30 cm (200 parts by weight)
Was washed with methanol to remove an oil agent (softening agent) adhering to the surface, and dried to obtain a fiber (b). In a mold having a linear groove of 40 cm in length, 0.5 cm in width, and 0.25 cm in depth, the fiber is stretched along the groove and allowed to stand, and the composition is added from above, and the fiber is added to the fiber. The composition was impregnated to obtain a polymerizable composition.

The solvent was gradually evaporated at room temperature under reduced pressure (about 760 mmHg) over about 10 hours to obtain a dental material. From the gas chromatographic analysis of the polymerizable monomer component in the impregnated fiber left in the groove, the remaining ethanol was below the detection limit (about 0.3% by weight). Observation of the surface condition of the dental material with an optical microscope showed that the dental material was good without leaching of the polymerizable monomer or protrusion of the filler. In addition, the operability when using the dental material as a reinforcing material for the bridge was evaluated using a working gypsum model (FIG. 1) used for manufacturing the bridge. In FIG. 1, reference numeral 1 denotes a gypsum abutment tooth model, and 2 denotes a resin separating agent (trade name: jacket spacer, manufactured by Kuraray). As shown in FIG. 2, after bridging to the occlusal surfaces of both abutment teeth of the working model, the dental material is pressed against the occlusal surface with fingers and produced.
At this time, if the polymerizable monomer adheres to the finger or if there is a defect such as a small amount of fibers of the dental material and easy separation, it is marked with x, and either one of these defects is When observed slightly, it was marked with △, and neither was recognized, and the case where the dental material adhered moderately to the gypsum model and the bridging form could be easily performed was evaluated as ○. In FIG. 2, reference numeral 3 denotes a dental material containing the converging yarn according to the present invention. The results are shown in Table 1.

Next, the reinforcing effect when the above-mentioned dental material was combined with a dental composite resin was examined. First, after immersing the material in the deepest part of a stainless steel mold (installed on a slide glass) of 2 × 5 × 30 mm, a light irradiator for dental technics (trade name: α-Light II, manufactured by Morita) Was subjected to photopolymerization. Further, after filling a composite resin (trade name: Esthenia, Kuraray Co., Ltd.) into the space of the mold above the material, the upper surface was pressed with a slide glass and photopolymerized with α-lite II. Subsequently, the mixture was heated at 110 ° C. for 15 minutes in a dental heat polymerization apparatus (trade name: KL-100, manufactured by Morita). After removing the cured polymer from the mold, it was stored in distilled water at 37 ° C. for 24 hours, and the bending strength was measured. The ratio between the fiber material and the composite resin was kept constant so that the glass fiber content of the cured product was about 20% by weight.

Span 20 mm, crosshead speed 1
A three-point bending test was performed using a universal testing machine (manufactured by Instron) under the condition of mm / min. Five test specimens were prepared for each sample, and the average value was used as the bending strength and flexural modulus of the sample. Further, the cross-sectional view of the test piece was observed with a scanning electron microscope (SEM) to check for the presence of air bubbles. Table 1 shows the results.

Comparative Example 1 A dental material was obtained in the same manner as in Example 1 except that the solvent (c) was not used. However, the desired material could not be obtained because the impregnating composition did not soak into the fiber bundles placed in the grooves.

Example 2 In Example 1, the amount of the diluent monomer 3G in the polymerizable monomer (a) was increased. That is, Bis-GM
A dental material was obtained in the same manner as in Example 1 except that 50 parts by weight of A and 50 parts by weight of 3G were used. The viscosity of the impregnating composition used at this time was about 5 cps at 25 ° C. The remaining ethanol was below the detection limit (about 0.3% by weight). In the same manner as in Example 1, the surface state of the material, the adhesion to a plaster model, the strength of the composite cured product, and the presence or absence of air bubbles were examined. Table 1 shows the results.

Comparative Example 2 A dental material was obtained in the same manner as in Example 2, except that the solvent (c) was not used. The viscosity of the impregnating composition used at this time was about 250 cps at 25 ° C. In the same manner as in Example 1, the surface state of the material, the adhesion to a plaster model, the strength of the composite cured product, and the presence or absence of air bubbles were examined. Table 1 shows the results.

Example 3 The same polymerizable monomer (a), solvent (c) and polymerization initiator (d) as in Example 1 were mixed and dissolved at the same compounding ratio. To 35 parts by weight of silica (trade name: Aerosil 130, manufactured by Nippon Aerosil), 7 parts by weight of a filler (e) surface-treated with 3- (meth) acryloyloxypropyltrimethoxysilane was added,
After mixing, the mixture was kneaded with three rollers (manufactured by Kodaira Seisakusho) to prepare a composition for impregnation. The viscosity of the impregnating composition was about 15 cps at 25 ° C.

Next, using the same fiber (b) as in Example 1,
After the fiber was impregnated with the above composition using the linear mold used in Example 1, the solvent was gradually evaporated and removed in the same manner as in Example 1 to obtain a dental material. The remaining ethanol was below the detection limit (about 0.3% by weight). In the same manner as in Example 1, the observation of the surface state, the adhesion to a plaster model, the strength of the composite cured product, and the presence or absence of bubbles were performed on this material. Table 1 shows the results.

Comparative Example 3 A dental material was obtained in the same manner as in Example 3 except that the solvent (c) was not used. However, since it was more difficult to impregnate than Comparative Example 1, a desired material could not be obtained.

[0053]

[Table 1]

Examples 4 to 5 As polymerizable monomers (a), 90 parts by weight of 2,2,4-trimethylhexamethylenebis (2-carbamoyloxyethyl) di (meth) acrylate (hereinafter referred to as UDMA) and 1, 10 parts by weight of 10-decanediol di (meth) acrylate (hereinafter, DD) or 75 parts by weight of UDMA and DD1
0 parts by weight and N, N '-(2,2,4-trimethylhexamethylene) bis [2- (aminocarboxy) propane-
For each combination of 15 parts by weight of [1,3-diol] tetra (meth) acrylate (hereinafter UTM),
110 parts by weight of anhydrous ethanol as the solvent (c) and 0.2 parts by weight of CQ and 0.1 parts by weight of DMA as the polymerization initiator (d) were added to each and mixed and dissolved.

The filler (e) subjected to the same surface treatment as in Example 3 was added to each of the above mixed solutions, mixed, and kneaded with three rollers to prepare a composition for impregnation. Each of the impregnating compositions has a viscosity of about 13 cp at 25 ° C.
s, about 18 cps. Further, impregnation into the fiber (b) was carried out in exactly the same manner as in Example 1 to obtain a desired dental material. The remaining ethanol was below the detection limit (about 0.3% by weight). In the same manner as in Example 1, observation of the surface state of the dental material, adhesion to a gypsum model, strength of the composite cured product, and presence or absence of air bubbles were performed on this material. Table 2 shows the results.

Comparative Examples 4 and 5 Dental materials were obtained in the same manner as in Examples 4 and 5, except that the solvent (c) was not used. However, as in Comparative Examples 1 and 3, it was difficult to impregnate, and a desired material could not be obtained.

Example 6 In Example 5, the diluent monomer D of the polymerizable monomer (a) was used.
The amount of D was increased. That is, a dental material was obtained in the same manner as in Example 1 except that 50 parts by weight of UDMA, 35 parts by weight of DD, and 15 parts by weight of UTM were used. The viscosity of the impregnating composition used at this time was about 22 cps at 25 ° C. The remaining ethanol was below the detection limit (about 0.3% by weight). In the same manner as in Example 1, the observation of the surface state, the adhesion to a plaster model, the strength of the composite cured product, and the presence or absence of bubbles were performed on this material. Table 2 shows the results.

Comparative Example 6 A dental material was obtained in the same manner as in Example 6, except that the solvent (c) was not used. The viscosity of the impregnating composition used at this time is about 4500 cps at 25 ° C.
Met. In the same manner as in Example 1, the observation of the surface state, the adhesion to a plaster model, the strength of the composite cured product, and the presence or absence of bubbles were performed on this material. Table 2 shows the results.

[0059]

[Table 2]

From the results shown in Tables 1 and 2, it is clear that the dental material of the present invention is excellent in all of impregnation property, unity of various materials used, and adhesion to a plaster model. Also, using only a dental composite resin (Esthenia) without using a dental material, a polymerized cured product was produced in the same manner as in Example 1, and the bending strength when a three-point bending test was performed was 200 MPa. From the fact that the flexural modulus was 22 GPa, it is clear that the dental material of the present invention has the highest reinforcing effect and excellent fiber adhesion.

Example 7 and Comparative Example 7 Gypsum abutment of the bridge from No. 5 (second premolar) to No. 7 (second molar) when the first molar No. 6 of the lower jaw is missing one tooth A tooth model was prepared, and a resin separating agent (jacket spacer) was applied (FIG. 1). The dental materials prepared in Example 5 and Comparative Example 6 were bridged on the occlusal surfaces of both abutment teeth, and photopolymerized for 1 minute by a light irradiator (α-light II) for dental technics, thereby obtaining a non-metallic material. A frame was produced (FIG. 2). Next, the core of the pontic tooth is formed of a dental composite resin (Esthenia) according to a conventional method, and the dental composite resin (Esthenia) is laid. After photopolymerization and heat treatment, shape modification and polishing are performed. Go to
The bridge was completed (Fig. 3). In FIG. 3, reference numeral 4 denotes a pontic tooth core, and reference numeral 5 denotes a dental composite resin.

For further measurement, an abutment tooth portion was prepared using a core composite resin (trade name: Clearfill Photocore, manufactured by Kuraray) and a dental composite resin (Esthenia), and the inner surface of the bridge and these abutments were prepared. After joining the tooth portion with a dental resin cement (trade name: Panavia Fluorocement, manufactured by Kuraray Co., Ltd.), it was stored in distilled water at 37 ° C. for 24 hours to prepare test bridge samples (Example 7 and Example 7, respectively). Comparative Example 7, FIG. 4). In FIG. 4, 6 is a dental composite resin (abutment portion), 7
Is a composite resin for a core, and 8 is a dental resin cement.

Next, the mechanical strength was measured using the test bridge sample described above. Using a universal testing machine (Instron) and a fatigue testing machine (device name: Servo Pulser, EHF-FD type, Shimadzu) for measurement,
A flat indenter with a width of 2 mm (made of stainless steel) is used as the indenter to apply a load, and a load is applied to the center of the pontic tooth (No. 6). A load was applied at 1 mm / min (FIG. 5). In the fatigue tester, a load was repeatedly applied at a load of 30 kgf and a repetition rate of 2 Hz (twice per second) (FIG. 6). 5 and 6, reference numeral 9 denotes a dental composite resin (load portion), and reference numeral 10 denotes a load indenter. The test was performed without fixing the bottom surfaces of both abutment teeth to the test pedestal corresponding to the gingival part. However, in order to avoid stress concentration due to contact between the mounting portion of both abutment teeth and the pedestal, the peripheral portion and the inside of the abutment tooth bottom surface were sufficiently provided with an R shape.

Similarly, in order to avoid stress concentration at the contact surface between the flat surface of the load indenter and the bridge sample, the occlusal surface of the pontic tooth of the bridge sample, which is the contact portion, is formed using a dental composite resin (Esthenia). And flattened. Under these conditions, two samples were prepared, and the resistance to static load when a fracture or crack occurred was determined as the fracture load resistance, or the number of times the fracture or crack occurred was defined as the fatigue fracture durability. did. Table 3 shows the results of the content of each fiber, the average breaking load resistance value and the average fatigue fracture durability.

Comparative Example 8 In order to examine the reinforcing effect of a dental material, a bridge was prepared in the same manner as in Example 7 and Comparative Example 7 except that no fiber was used and only a dental composite resin (Esthenia) was used. It was fabricated and similarly subjected to a destructive test and a fatigue test. The results are shown in Table 3.

[0066]

[Table 3]

From Table 3, it is clear that the bridge produced using the dental material of the present invention has excellent mechanical strength and fatigue durability. In addition, since the material has a good surface condition and good adhesion to a gypsum model, the work can be performed easily, and the production time is shorter than that of a conventional polymer material which is simply impregnated with a polymer matrix and fibers. Can be shortened.

Example 8 Using the dental material produced in Example 5 and a dental composite resin (Esthenia), an upper structure of an implant was produced in the same manner as in Example 7 (FIG. 7). In FIG. 7, reference numeral 11 denotes an implant. As in the case of Example 7, it could be easily produced.

Example 9 An artificial tooth was produced in the same manner as in Example 7 using the dental material produced in Example 5 and a dental composite resin (trade name: Ceced 2, Kuraray) (FIG. 8). . In FIG. 8, reference numeral 12 denotes a dental composite resin (Seceed 2)
It is.

Example 10 An abutment was produced in the same manner as in Example 7 using the dental material produced in Example 5 and a dental composite resin (clearfill photo core) (FIG. 9). In FIG. 8, reference numeral 13 denotes a dental composite resin (clear fill photo core).

Example 11 Instead of the E-glass fiber bundle used in Examples 1 to 10 or Comparative Examples 1 to 7, E glass fiber obtained by plain weaving a yarn-shaped single fiber having a fiber diameter of 9 μm in an intersecting manner was used. Textile (trade name: Glaslon, code. H103C3NT40F)
S, manufactured by Asahi Fiberglass Co., Ltd., the glass fiber surface of which has been treated with a silane-based coupling agent) using 200 parts by weight of the same polymerizable monomer (a), solvent (c), A dental material was prepared in the same manner using the initiator (d) and the filler (e). A dental material using the woven fiber, a dental material using the convergent fiber prepared in Example 5, and a denture base resin (trade name:
Example 7 using Parapress, Heraeus Krutua)
A denture base was prepared in the same manner as in (1) (FIG. 10). FIG. 10 is a schematic view of a denture base, in which 14 is a dental material containing a woven fabric, 15 is an artificial tooth, and 16 is a denture base resin.

Example 12 Instead of the bundled yarn of E glass fiber used in Examples 1 to 10 or Comparative Examples 1 to 7, a yarn-shaped single fiber having a fiber diameter of 7 μm was knitted with a thickness of 0.2 mm and a width of 2 mm. Knitting of E-glass fiber (trade name: glass flat string, code.ECE2)
251 / 2.44S, manufactured by Nippon Sheet Glass)
Using fibers treated with 40 parts by weight of 3- (meth) acryloyloxypropyltrimethoxysilane, the same polymerizable monomer (a) as in Example 5, a solvent (c),
A dental material was produced in the same manner using the polymerization initiator (b) and the filler (e). A jacket crown was produced in the same manner as in Example 7 using a dental material using the knitted woven fiber and a dental composite resin (trade name: Art Glass, manufactured by Heraeus Krutour) (FIG. 11). In FIG. 11, reference numeral 17 denotes a dental material containing a knitted fabric, and reference numeral 18 denotes a dental composite resin (art glass).

As described above, a bridge, a superstructure of an implant, an artificial tooth, an abutment, a denture base, and a jacket crown, which are typical examples of a dental prosthesis, were manufactured using the dental material of the present invention. All were excellent in mechanical strength and fatigue durability. The embodiment shows a typical application example of the dental prosthesis, and is sufficiently applicable to other dental prostheses.

[0074]

According to the present invention, the polymerizable monomer (a), the fiber (b), the solvent (c) and the polymerization initiator (d) are prepared in advance.
And a method for producing a dental material by removing the solvent (c) from the composition. According to the present invention, a dental material having excellent adhesion between a polymerizable monomer and a fiber can be obtained by a simple operation. Such a dental material can be formed into a dental prosthesis having excellent mechanical strength and good handleability, and having excellent mechanical strength and fatigue durability.

[Brief description of the drawings]

FIG. 1 is a gypsum abutment model coated with a resin separating agent.

FIG. 2 shows a method of bridging the dental material of the present invention between both abutment teeth,
It is a frame form of a bridge formed by photopolymerization.

FIG. 3 shows a bridge according to the present invention in which a dental composite resin is laid in the form of a bridge frame.

FIG. 4 is a schematic view of a bridge sample of the present invention produced by bonding an abutment portion prepared using a core composite resin and a dental composite resin and an inner surface of a bridge with a dental resin cement. .

FIG. 5 is a schematic diagram of a static load test of the bridge sample of the present invention.

FIG. 6 is a schematic diagram of a fatigue test of the bridge sample of the present invention.

FIG. 7 is an example of an implant superstructure of the present invention.

FIG. 8 is an example of the artificial tooth of the present invention.

FIG. 9 is an example of an abutment building of the present invention.

FIG. 10 is an example of a denture base of the present invention.

FIG. 11 is an example of a jacket crown of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Gypsum abutment model 2 ... Resin separating agent 3 ... Dental material (contains a converging thread) 4 ... Pontic tooth core 5 ... Dental composite resin 6 ... Dental composite resin (abutment part) 7 ... Core Composite resin for dental use 8 ... Dental resin cement 9 ... Dental composite resin (loading part) 10 ... Loading indenter 11 ... Implant 12 ... Dental composite resin 13 ... Dental composite resin 14 ... Dental material (including fabric) 15 ... Artificial Tooth 16 ... Denture base resin 17 ... Dental material (including knitted material) 18 ... Dental composite resin

Claims (7)

[Claims] In a method for producing a dental material containing fibers, a polymerizable monomer (a), a fiber (b), and a solvent (c) are prepared in advance.
And producing a polymerizable composition comprising a polymerization initiator (d),
Thereafter, a method for producing a dental material, comprising removing the solvent (c) from the composition. 2. A fiber (b) of 20 to 800 parts by weight and a solvent (c) of 3 to 100 parts by weight of the polymerizable monomer (a).
The method for producing a dental material according to claim 1, comprising 0 to 300 parts by weight and 0.01 to 5 parts by weight of the polymerization initiator (d). 3. The method according to claim 1, further comprising a filler (e).
Or the method for producing a dental material according to 2. 4. The method for producing a dental material according to claim 3, wherein the content of the filler (e) is 5 to 150 parts by weight based on 100 parts by weight of the polymerizable monomer (a). 5. The fiber (b) is a short fiber, a strand,
The method for producing a dental material according to any one of claims 1 to 4, wherein the method is at least one or more fibers selected from roving, yarn, mat, sheet, cloth, ribbon, tape, rope, and straw. 6. A dental material obtained by the method according to claim 1. 7. A dental prosthesis containing a dental material obtained by the production method according to claim 1.