JPH10137266A - Repair material and repair method for plaster model for dental technique - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to easily execute the correction molding of a plaster model, to harder this model up to the inside in a very short time even if its thickness is large and further to avoid the degradation in working environment, and to generate less smell. SOLUTION: This repair material consists of a transparent or translucent photosetting compsn. which consists of a photopolymerizable prepolymer and/or photopolymerizable monomer as a chief material, contains a photopolymn. initiator and is made gel-like by compounding a thixotropic property imparting agent therewith. The correction molding of the section to be repaired of the plastic model for dental technique is executed and the correction molding part is hardened by irradiating this part with light (more particularly visible light).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a repair agent for a plaster model for dental technology and a method for repairing the same using the repair agent.

[0002]

2. Description of the Related Art Gypsum is widely used as a model for reproducing a patient's mouth for dental technics. That is, first, an impression is made from the oral cavity of the patient, plaster is injected into the impression, a model is produced, and a prosthesis is produced based on the model. In this case, the portion of the gypsum model containing air bubbles may be lost, chipped due to careless handling, or may need to be corrected due to excessive shaving.

In order to repair a gypsum model, a gel-like 2-cyanoacrylate-based instant adhesive has been used.

[0004]

A method for repairing a gypsum model using a gel-like 2-cyanoacrylate-based instant adhesive utilizes the quick-curing property of 2-cyanoacrylate. The problem is that the curing speed becomes extremely slow when the thickness is thick, and that once used and the rest is stored, it may naturally cure in the container even if the cap is tightly closed. There is.

In order to solve this problem, it has been attempted to accelerate the curing by spraying an accelerator after performing correction molding with a 2-cyanoacrylate-based instant adhesive, but the accelerator is mainly composed of amines. When the correction molding part is thick, even if the surface side cures promptly with the accelerator, it will not cure to the inside without considerable time, and the remaining part should be stored. However, there are still problems such as the fact that the curing progresses when it is left, and the fact that the fingers adhere to each other unless they are immediately wiped off when they adhere to the finger.

Accordingly, the present inventors have formulated a high-viscosity paste by blending a large amount of fine fillers such as quartz glass, borosilicate glass, silicate, calcium phosphate, and α-quartz into an ultraviolet curable resin or a visible light curable resin. (Opaque) photo-curable resin composition for tooth restoration (composite resin, "Industrial Materials September 1996, 75-
(Refer to p. 79)) for the repair of gypsum models, but the curing depth when irradiating with ultraviolet or visible light is up to about 2-3 mm. Did not cure easily.

According to the present invention, under such a background, the correction molding of the gypsum model can be easily performed, and even when the gypsum model is thick, the inside can be hardened in a very short time.
It is still another object of the present invention to provide a repair agent for a gypsum model for dental technics, which does not deteriorate the working environment because the odor is small, and a repair method using the repair agent.

[0008]

A repair agent for a gypsum model for dental technology of the present invention contains a photopolymerizable prepolymer and / or a photopolymerizable monomer as a main component, and contains a photopolymerization initiator,
Further, the composition is characterized by comprising a transparent or translucent photocurable composition formed into a gel by mixing a thixotropic agent.

The method for repairing a gypsum model for dental technology according to the present invention comprises a photopolymerizable prepolymer and / or a photopolymerizable monomer as a main component, a photopolymerization initiator, and a gel-like composition obtained by mixing a thixotropic agent. Using a repairing agent composed of a transparent or translucent photocurable composition, performing correction molding of the repaired portion of the gypsum model for dental technology, and then performing light irradiation to cure the correction molding portion. It is a feature.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.

Examples of the gypsum model for dental technics include models prepared by ordinary methods using ordinary gypsum, anhydrite, and cemented gypsum for dental technics.

In the present invention, as a repair agent for a gypsum model for dental technology, a gel is obtained by blending a photopolymerizable prepolymer and / or a photopolymerizable monomer as a main component, a photopolymerization initiator, and a thixotropic agent. A transparent or translucent photocurable composition in the form of a curable composition is used.

Examples of the photopolymerizable prepolymer include polyester acrylate, polyester urethane acrylate, polyurethane acrylate, epoxy acrylate, polyol acrylate, and silicone acrylate. Acrylate is a concept that includes methacrylate.

Examples of the photopolymerizable monomer include various acrylates such as monofunctional acrylate, bifunctional acrylate, and trifunctional or higher acrylate. As described above, acrylate is a concept including methacrylate.

The photopolymerizable prepolymer and the photopolymerizable monomer can be used alone. However, the photopolymerizable prepolymer alone tends to have a high viscosity, and the photopolymerizable monomer alone tends to have excessive fluidity. It is particularly preferred to use both. The proportion used at this time is not generally defined because it varies depending on the kind thereof, but it is so determined that the weight ratio of the photopolymerizable prepolymer and the photopolymerizable monomer is 95: 5 to 5:95. It is desirable to do.

As the photopolymerization initiator (including a sensitizer and an accelerator), those which respond to light having a wavelength of 200 to 600 nm are used. In this case, in order not to harm the workers,
It is particularly preferred to use photoinitiators which are sensitive even at visible light wavelengths of from 320 to 600 nm, in particular from 380 to 600 nm. The wavelength range of visible light is about 380 to 780 nm,
The wavelength range of the ultraviolet light is smaller than that, up to about 100 nm.

As the thixotropy-imparting agent, anhydrous silicate, hydrous silicate, bentonite, hydrogenated castor oil type, wax type, dibenzal sorbite type and the like are used. In particular, colloidal silica or fumed silica is important, and the blending amount at this time is often about 1 to 10% by weight based on the entire photocurable composition.

The photocurable composition further includes a non-photopolymerizable polymer, filler, pigment, stabilizer, antibacterial agent, plasticizer, solvent, surfactant, dispersant, various modifiers,
Additives such as fragrances can be added as needed. However, since fillers and pigments may impair photocurability, it is desirable not to use them, and even when they are used, care should be taken that the amount used is small enough not to impair photocurability.

The photocurable composition is formed into a gel by adding the above-mentioned thixotropic agent. The gel-like means a grease-like, putty-like, clay-like or mayonnaise-like, and does not have fluidity in an amount used for repairing a gypsum model. The gel-like photocurable composition is made transparent or translucent so as to be cured promptly to a deep part upon irradiation with light. Here "transparent or translucent"
And when cured to a thickness of 1 mm from the top of the printing surface,
It shall mean that the printed characters are legible through the layer of the cured product.

The photocurable composition desirably decolorizes (bleachs or discolors) before and after curing. This is because the time point of completion of curing can be visually recognized. To enable discoloration, a small amount of a dye unstable to light is added to the system, and a specific functional group (for example, a basic group such as an amino group) is used as a photopolymerization initiator (sensitizer or accelerator). An appropriate method is adopted, including a method using a material having Is raised.

The above-mentioned repair agent comprising the gel-like photocurable composition is desirably contained in a light-shielded discharge container with a nozzle. A typical example of the discharge container is a tube container made of aluminum. If the nozzle portion is transparent, the contents are hardened, so that this portion is also shielded from light. In addition to aluminum tube containers, plastics laminate tubes and polyolefin containers can be used as long as they have light-shielding properties.

In repairing the gypsum model for dental technology, first, a repair molding of the repaired portion of the gypsum model for dental technology is performed using the above-described repair agent made of the gel-like photocurable composition. Correction molding may be performed, for example, by discharging a required amount of the composition from a discharge container with a nozzle to a repaired site, and appropriately performing correction with a drill after curing.

After the correction molding of the repaired portion is performed, light irradiation is performed to cure the correction molding portion. As a light source for performing light irradiation, a metal halide lamp, a halogen lamp, a xenon lamp, a fluorescent lamp, a high-pressure mercury lamp, a low-pressure mercury lamp, or the like is used. However, since curing is preferably performed by visible light, a metal halide lamp, a halogen lamp, a xenon lamp, or the like is used as a light source. Is desirable. If the environment allows, you can simply use sunlight to keep it near the window.

<Action> In the present invention, since a repairing agent comprising a transparent or translucent photocurable composition formed into a gel by mixing a thixotropy-imparting agent is used, the gypsum model for dental technology is used. Correction molding can be freely performed on the repaired portion, such as filling of a defective portion and formation of a bulge.

Since it has photocurability, it is possible to cure the inside of the mold in a very short time on the order of a second even in the case of thick correction molding, and the hardness at that time can be freely adjusted. In addition, it does not cure unless it is irradiated with light, so it has good storage stability, it can be carefully repaired, and it can be irradiated with light at a later time. There is also an advantage that can be set to. In addition, smooth curing in the visible light wavelength range that does not harm the worker is also possible. Also, the odor is small and the working environment is not deteriorated.

Therefore, the repairing agent and the repairing method of the present invention
This is significantly more advantageous than the conventional method using a 2-cyanoacrylate-based instant adhesive and an accelerator.

[0027]

The present invention will be further described with reference to the following examples. Hereinafter, "parts" refers to parts by weight. In each of the examples, a visible light sensitive type is used as a photopolymerization initiator.

Example 1 A visible light-curable photocurable resin composition having the following formulation was prepared. -Bisphenol A ethylene oxide adduct diacrylate 80 parts-Dipentaerythritol hexaacrylate 20 parts-Diethylthioxanthone (photopolymerization initiator) 1 part-Isoamyl p-dimethylaminobenzoate (promoter) 2 parts-Colloidal silica (Japan) 4 parts of "Aerosil # 200" manufactured by Aerosil Co., Ltd.-0.2 parts of silicone dispersant ("BYK-405" manufactured by BYK Chemie Co., Ltd.)-0.001 part of blue dye (which discolors to yellow by light)

The above composition was vacuum-defoamed and stirred with a planetary mixer to obtain a repair agent consisting of a gel-like translucent composition. This repair agent is filled from the opening at the rear of the aluminum tube container and the rear is sealed,
A light-shielded nozzle was attached to the mouth of the tube container.

The repair agent was applied on a gypsum model by raising it to a thickness of 5 mm and a diameter of 10 mm, and then applied to a halogen lamp (Philips “JCR-100V • 150WA, 4WA”).
When irradiation was performed for 10 seconds at an irradiation distance of 5 cm using "00 to 500 nm", the composition which was blue at the time of coating was completely cured and turned into yellow. During the application and curing process, no odor was felt. When the cured product was forcibly peeled, it was confirmed that the surface of the gypsum model was broken, and the cured product was cured to the bottom.

In place of the above-mentioned halogen lamp, 1 KW
When irradiation was performed at an irradiation distance of 12.5 cm using a metal halide lamp, complete curing was achieved in 2 seconds.

Example 2 Four parts of "Aerosil # 200" manufactured by Nippon Aerosil Co., Ltd. in Example 1 were replaced with "Aerosil RX-20" manufactured by Nippon Aerosil Co., Ltd.
Example 1 was repeated except that 5 parts of "0" (a surface treatment type having good dispersion stability) was used and the addition of the dispersant "BYK-405" was omitted. As a result, a gel composition having higher transparency than the composition of Example 1 was obtained. When the same curing test as in Example 1 was performed using the repairing agent composed of this composition, the same good results as in Example 1 were obtained.

Example 3 In Example 1, 4 parts of "Aerosil # 200" manufactured by Nippon Aerosil Co., Ltd. were replaced with 5 parts of "Disparon 305" hydrogenated castor oil-based flow control agent manufactured by Kusumoto Kasei Co., Ltd. Other than omitting the addition of “BYK-405”,
Example 1 was repeated. As a result, a gel-like composition having a slightly higher transparency and a slightly lower thixotropy than the composition of Example 1 was obtained. When the same curing test as in Example 1 was performed using the repairing agent composed of this composition, the same good results as in Example 1 were obtained.

Example 4 A visible light-curable photocurable resin composition having the following formulation was prepared. The term "EO adduct" refers to an ethylene oxide adduct. As the photopolymerization initiator, 2-benzyl-
2-Dimethylamino-1- (4-morpholinophenyl) butanone-1 was used. -Bisphenol type epoxy acrylate 60 parts-Trimethylolpropane EO adduct triacrylate 20 parts-Phenoxyethyl acrylate 20 parts-Photopolymerization initiator 3 parts-Colloidal silica "Aerosil RX-200" 5 parts-Blue dye (by light (Discolored to yellow) 0.001 parts

The above composition was vacuum-defoamed and agitated with a planetary mixer to obtain a repairing agent consisting of a gel-like composition having good transparency, and filled in a tube container. This repair agent was applied on a gypsum model by raising it to a thickness of 5 mm and a diameter of 10 mm, and irradiated with the halogen lamp described in Example 1 at an irradiation distance of 5 cm for 5 seconds.
The composition that was blue at the time of coating was completely cured and turned yellow. During the application and curing process, no odor was felt. When the cured product was forcibly peeled, it was confirmed that the surface of the gypsum model was broken, and the cured product was cured to the bottom.

COMPARATIVE EXAMPLE 1 A repair agent consisting of a commercially available gel-like ethyl 2-cyanoacrylate-based instant adhesive was applied on gypsum to a thickness of 5 mm and a diameter of 10 mm.
Then, a commercially available amine-based accelerator was spray-coated thereon. The surface of the cured product was quickly cured, but after one minute, the cured product was forcibly peeled off, and it was found that the bottom was in an uncured state.

Comparative Example 2 A paste-like or clay-like resin composition was selected from commercially available dental (for denture) visible light curable resin compositions which had been made highly viscous by the addition of a large amount of filler (both were opaque). ), 5 mm thick and 10 mm diameter on the gypsum model in the same manner as in Example 1.
mm, and irradiation was performed using the halogen lamp described in Example 1 at an irradiation distance of 5 cm for 20 seconds. The surface of the cured product was cured, but the bottom was in an uncured state. The thickness of the cured portion was measured to be 2.5 mm when using the paste-like composition and 1.8 mm when using the clay-like composition.

When the irradiation time was 1 minute, the curing hardly proceeded, and the thickness of the cured portion was 3 mm when using a paste-like composition, and 2.2 mm when using a clay-like composition. there were.

[0039]

As described in the section of the action, the repairing agent and the repairing method of the present invention can freely perform correction molding, such as filling a defective portion or forming a bulge, with respect to a repaired portion. Even if there is a correction molding with a mold, it can be cured inside in a very short time on the order of seconds and the hardness can be adjusted freely, the timing of curing can be set arbitrarily, smooth in the wavelength range of visible light It has excellent effects such as being safe because it can be cured, having a low odor and not deteriorating the working environment.

Claims (5)

[Claims] A transparent or translucent photocurable composition comprising a photopolymerizable prepolymer and / or a photopolymerizable monomer as a main component, a photopolymerization initiator, and a gel formed by mixing a thixotropic agent. A repair agent for a plaster model for dental technics, characterized by being made of a material. 2. The repair agent according to claim 1, wherein the photocurable composition is curable by visible light. 3. The repair agent according to claim 1, wherein the photocurable composition undergoes discoloration before and after curing. 4. The repair agent according to claim 1, wherein the photocurable composition is contained in a light-shielded discharge container with a nozzle. 5. A transparent or translucent photocurable composition comprising a photopolymerizable prepolymer and / or a photopolymerizable monomer as a main component, a photopolymerization initiator, and a gel formed by adding a thixotropic agent. Repairing method for a repaired portion of a gypsum model for dental technics using a repair agent composed of a product, and then performing light irradiation to cure the corrected molding part, thereby repairing the gypsum model for a dental technician. .