JP2004180976A - Artificial tooth and manufacturing method of the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To simply provide a sophisticated artificial tooth without sacrificing any molding precision. <P>SOLUTION: This method uses a means which injects or pours resin showing flexible viscosity at a temperature average or higher than this into an elastic impression mold which never loose flexibility at its cooling curing temperature without changing its normal state, cools the resin, releases the cooled and cured resin from the elastic impression mold, and thereafter polymerizes and cures the resin. As the resin, photopolymerization type resin is used. After pouring etc. the photopolymerization type resin to the side of a releasing surface of the elastic impression mold with a desired thickness, core material consisting of another material is supplied to its residual part. In addition, when force-fitting the core material, the elastic impression mold is heated from outside to soften the photopolymerization type resin. Consequently, sophisticated artificial tooth can be produced with techniques of a comparatively small-scale. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an artificial tooth that reproduces a complicated surface shape with high accuracy, and a method for manufacturing the artificial tooth.
[0002]
[Prior art]
Conventionally, various resin molded articles and methods for producing the same have been proposed. Among them, inventions disclosed in Patent Literature 1 and Patent Literature 2 (hereinafter, referred to as prior inventions 1 and 2, respectively) as a method for manufacturing an artificial tooth which is required to faithfully reproduce a complicated surface shape. Is known.
[0003]
That is, the prior application invention 1 is a method for producing an artificial tooth, characterized by pouring porcelain powder mud into an impression type (core), freezing it, and drying and firing the porcelain molded in a frozen state. . According to the prior invention 1, by drying the porcelain material in a frozen state, it is possible to manufacture a sophisticated artificial tooth that faithfully reproduces the impression type.
[0004]
On the other hand, in the prior application invention 2, the porcelain powder mud is poured into the impression mold, and the porcelain powder mud is pressurized and compacted. After completion, the porcelain is released from the impression mold. In this method, the frosted and dried porcelain does not become porous (porous) because it freezes in a state in which the water is removed as much as possible, and the surface has a very dense structure with a smooth surface. This is an improvement of the prior invention 1 in that a high artificial tooth can be obtained.
[0005]
In addition, since these prior inventions 1 and 2 are both methods for manufacturing an artificial tooth using a so-called cooling method, they can faithfully reproduce an impression type having a complicated uneven shape due to the viscosity of porcelain, and also have an impression Since silicon rubber is used as the mold, it is possible to collect complicated surface shapes, and even if the porcelain material after freezing has an undercut shape, the frozen porcelain material can be easily removed from the impression mold. There is an advantage that the mold can be released.
[0006]
[Patent Document 1]
Japanese Patent Application Laid-Open No. 10-305036 [Patent Document 2]
JP-A-11-267139
[Problems to be solved by the invention]
However, the problems to be solved still remain in the first and second inventions. That is, in the above-mentioned prior inventions 1 and 2, it is assumed that a material that maintains its shape after thawing and is cured as a porcelain material and that hardens to the final strength by firing is used. In addition, it was required to use a large-scale means of firing. In addition, there is also a problem that it shrinks after firing and cannot reproduce the same form. In other words, these prior inventions 1 and 2 are concentrated on dental technicians, and therefore, the practitioner needs some experience and skill.
[0008]
The present invention has been made to solve the above-described problem, and an object of the present invention is to obtain a more sophisticated artificial tooth more easily without sacrificing molding accuracy at all.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides a resin having fluid viscosity at room temperature or higher, which is embedded and cooled in an elastic impression mold which does not lose flexibility at its cooling and solidifying temperature in a normal state, and is cooled and solidified. Is a method for producing an artificial tooth using a means for polymerizing and curing the resin after releasing from the elastic impression mold, and an artificial tooth produced by the method. Since the resin used has a fluid viscosity such as clay-like or paste-like at least at room temperature, it can be densely filled in a mold having a complicated shape. Further, the resin maintains its form even after release from the mold by cooling and solidifying, and in this state, is polymerized and cured under appropriate conditions. On the other hand, the elastic impression type has flexibility like rubber or silicone, maintains flexibility even after the resin is cooled and solidified, and has good releasability from the polymerized resin, so that it has a complicated female shape. The resin solidified by cooling can be easily released. Here, "embedding" means that depending on the viscosity of the resin, if the clay is high, the clay is injected with an instrument or the like, and if the viscosity is low, the resin is poured into the resin. This is a broad concept of charging into a mold, and there is no limitation on the charging method or the packing method. Further, in the case of a resin having a high viscosity (hard), a method of embedding the resin in a state where it is softened by heating is also included. On the other hand, it is not excluded that the resin is polymerized and cured in the elastic impression mold before releasing. Even after polymerization curing, the resin can be taken out of the elastic impression mold. However, if it is taken out before polymerization, final adjustment in the model (articulator and the like) and the oral cavity of the patient can be easily performed.
[0010]
As the resin to be used, for example, a heat polymerization type resin or a room temperature polymerization type resin is applicable, and it is preferable to use a photopolymerization type resin. This is because the operability is good, the variety in color and viscosity, and the hardness after polymerization are abundant, the polymerization rate is high, and the polymerization apparatus is simple and easily available. In addition, the shape can be maintained by cooling and solidifying, and after hardening by light irradiation, a high hardness comparable to the enamel layer of the natural tooth can be obtained. This photopolymerizable resin basically becomes soft when heated and becomes hard when cooled. However, there are slight differences in curing conditions, surface smoothness after curing, cutting workability, etc., depending on the type, so the type of light-curing resin to be used is selected according to the conditions required for the artificial tooth. I do. The photopolymerizable resin is a resin that polymerizes under light irradiation conditions such as a predetermined wavelength, illuminance, and time, and generally does not polymerize with light from a fluorescent lamp. For this reason, careless polymerization during molding is avoided and handling is easy.
[0011]
Although artificial teeth can be obtained only with light-cured resin, it is preferable to combine light-cured resin with other materials in consideration of shape maintenance and deformation after cooling and solidification, and other costs. . For example, after injecting or pouring light-curing resin on the release surface side with the elastic impression type, by putting a core material made of another material into the remainder, the amount of light-curing resin used can be reduced. It is also possible to avoid inadvertent deformation and the like.
[0012]
When the artificial tooth is compounded and molded as described above, the core material (base material) is preferably selected from a material having high adhesion at the boundary with the photopolymerized resin. This is for obtaining an integral bonding force as a product. Examples of the means include a method in which a net or the like is interposed on the composite boundary, or a method in which the boundary surface of the core material is roughened to increase the boundary surface area. Is used. This is because it has been confirmed by experiments of the present inventors that the room-temperature-polymerizable resin exhibits high adhesion to the photopolymerizable resin during the polymerization. Another advantage is that the resin is polymerized at room temperature and does not require a large-scale apparatus. However, since the core material can sometimes function as a male mold, in that case, it is not necessary to consider adhesion to the photopolymerizable resin, and conversely, emphasis should be given to peelability.
[0013]
On the other hand, in order to densely fill the elastic impression type with the photocurable resin, it is preferable to use a pre-cured solid as the core material and press-fit this core material into the elastic impression type. This individual corresponds to, for example, a resin individual or a metal frame coated with opaque resin.
[0014]
Further, in order to more densely fill the photopolymerizable resin, it is preferable to heat the core at a temperature at which the photopolymerizable resin is softened at the time of press-fitting. The temperature at which the photopolymerizable resin shifts from the normal state to the softened state is approximately 40 to 50 ° C. For this reason, as the heating means, a heating method using a dryer can be adopted in addition to the simplest water bath.
[0015]
On the other hand, by forming the elastic impression mold from silicone rubber, higher flexibility can be obtained, and furthermore, extremely high releasability from the photopolymerizable resin after cooling and solidification can be obtained. Can be.
[0016]
An artificial tooth is mentioned as a specific application example of the above-described means. In addition, the artificial tooth is used in a broad sense including dentures such as dentures having a floor or a clasp, in addition to a partial prosthetic material of an artificial tooth or a natural tooth.
[0017]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 shows a resin molded product of the present invention, which is used as an artificial tooth. In the figure, reference numeral 1 denotes a pseudo enamel layer obtained by polymerizing and curing a photopolymerizable resin, and the photopolymerized layer 1 has a hardness substantially equal to that of the enamel layer of natural teeth. In addition, by appropriately mixing and using a coloring material, an aesthetic appearance close to that of natural teeth can be achieved. Reference numeral 2 denotes a core material covered with the pseudo enamel layer 1, which functions as a base material, and specifically corresponds to a material obtained by polymerizing and curing a room temperature-type polymerization resin. By using a room temperature polymerized resin as the core material 2, the adhesiveness with the pseudo enamel layer 1 made of the photopolymerizable resin is increased, and an integral bonding force required as an artificial tooth is exhibited. However, all of the artificial teeth may be molded with the light-curable resin, or all of the artificial teeth may be molded with another resin, and the present invention includes molding with a combination of a plurality of resins other than those exemplified here. . What is required in the present invention is to manufacture an artificial tooth by the method described below.
[0018]
Therefore, the manufacturing method of the present invention will be described with an example of artificial tooth preparation. FIG. 2 shows the working process. First, in step 1, an impression of a tooth is collected and a mold is prepared. This mold is an elastic impression mold 3 made of a flexible material such as silicon rubber, and a female mold can be manufactured according to a conventional method.
[0019]
Next, in step 2, a fixed amount of the photopolymerizable resin 4 is injected into the elastic impression mold 3. The injection method at this time may employ a means corresponding to the viscosity, and is not necessarily limited to the method using the illustrated injector. Further, an amount suitable for constructing the pseudo enamel layer described above may be injected. Since the photopolymerizable resin exhibits fluid viscosity at room temperature, it can be injected into the elastic impression mold 3 without any gap, and is easy to handle.
[0020]
Subsequently, in step 3, the room temperature polymerization type resin 5 is put into the elastic impression type 3 from above the photopolymerization type resin 4, and the elastic impression type 3 is left at room temperature for a certain time in this state, and the room temperature polymerization type resin 5 is removed. Polymerize and cure. The room temperature polymerization type resin 5 becomes the above-mentioned core material 2 by polymerization and curing, and it should be noted that the room temperature polymerization type resin 5 has good adhesion to the photopolymerization type resin 4. In this step 3, a solid made of another material to which a rough shape of an artificial tooth has been previously added can be added as the core material 2. For example, it is a metal frame coated with a solid resin (resin solid) or an opaque resin, and these can be further compounded. Further, in order to prevent deformation before polymerization and curing, a reinforcing material such as a metal wire may be applied at the same time. Therefore, in the subsequent steps, these components are collectively referred to as the core material 2 except for the light-curable resin 4.
[0021]
Step 4 is a good example for more elaborately transferring the impression (printing, duplication) to the light-curing resin 4 by pressing the core 2 into the elastic impression mold 3 and The photopolymerizable resin 4 is softened by applying pressure and heating the elastic impression mold 3 from the outside. This is a so-called hot pressing process. As the heating means, it is sufficient that the photopolymerizable resin 4 is softened. For example, in addition to the indirect method of immersing the elastic impression mold 3 in which the photopolymerizable resin 4 is embedded at 40 to 50 ° C., A direct method of heating and softening the photopolymerizable resin 4 before embedding can be employed. As a method of preheating the photopolymerizable resin 4 before embedding in the mold 3, it is convenient to use a dryer. Note that the heating method in this step is not limited, and the step can be omitted as appropriate.
[0022]
Subsequently, in step 5, the elastic impression mold 3 is put in a freezer for a certain period of time, and the photopolymerizable resin 4 is cooled and solidified. The temperature and time required for cooling and solidifying are adjusted according to the characteristics of the photopolymerizable resin 4 to be used. In addition, in the case of the photopolymerizable resin 4, the molecular vibration is reduced at a low temperature and does not freeze by cooling, and the resin is hardened. The hardened photopolymerizable resin resembles a hard rubber.
[0023]
When the cooling and solidification is completed, the elastic impression mold 3 is removed from the freezer, and the mold is released in step 6 by waiting for the internal resin to rise to room temperature. At this time, since the elastic impression mold 3 does not lose its flexibility, the elastic impression mold 3 can be easily released from an undercut artificial tooth. In addition, since the elastic impression mold 3 is made of silicone rubber, the releasability from the cooled and solidified photopolymerizable resin 4 is good, and the mold release operation is further facilitated.
[0024]
Then, in step 7, as a final step, the release object is irradiated with light of a predetermined wavelength and illuminance for a predetermined time to photopolymerize the photopolymerizable resin 4, and after the curing, a final finish such as deburring or polishing is appropriately performed. Get the finished product. It is to be noted that, before the polymerization and curing, if the resin is heated, morphological adjustment (including separately building) can be performed. In other words, after release, by adapting the resin to the articulator and the oral cavity of the patient before polymerization, it is possible to make fine final adjustments, and in addition to elaboration, to improve the feeling of wearing in the oral cavity be able to.
[0025]
【Example】
As an example of the above-mentioned manufacturing method, using Heraus Kulzer's Parapress Vario as the injection resin to be the core material 2, the resin is injected into the elastic impression die 3, and the resin is pressed in hot water at 55 ° C. for 15 minutes. After polymerization, it was cooled. As a result, a strong bonding state with the photopolymerizable resin 4 could be confirmed.
[0026]
【The invention's effect】
As described above, according to the present invention, an artificial tooth having a complicated shape can be elaborated. In addition, it is easy to transfer the impression and the subsequent mold release, and does not require a large-scale apparatus for curing the resin, and it is possible to manufacture a sophisticated artificial tooth with a relatively small technical skill. Therefore, the time and effort required conventionally can be greatly reduced, and the cost is also advantageous.
[Brief description of the drawings]
FIG. 1 is a conceptual diagram showing an artificial tooth as an application example of the present invention. FIG. 2 is a process diagram showing an example of a manufacturing process of the artificial tooth.
DESCRIPTION OF SYMBOLS 1 Pseudo enamel layer 2 Core material 3 Elastic impression type 4 Light curing resin 5 Room temperature curing resin

Claims (10)

A resin exhibiting a fluid viscosity in a normal state is embedded in an elastic impression mold that does not lose flexibility at the cooling and solidifying temperature of the resin and cooled, and after the cooled and solidified resin is released from the elastic impression mold, the resin is cooled. An artificial tooth characterized by being polymerized and cured. The artificial tooth according to claim 1, wherein the resin is a photopolymerizable resin. 3. The artificial tooth according to claim 2, wherein the photopolymerized resin is applied only to the release surface side from the elastic impression type, and the remainder is made of a core material made of another material. 4. The artificial tooth according to claim 1, wherein the elastic impression type is made of silicone rubber. A resin exhibiting a fluid viscosity at room temperature or higher is embedded in an elastic impression mold that does not lose its flexibility at the cooling and solidifying temperature of the resin in a normal state, cooled, and the cooled and solidified resin is released from the elastic impression mold. Then, a method for producing an artificial tooth, comprising polymerizing and curing the resin. The method for producing an artificial tooth according to claim 5, wherein a photopolymerizable resin is used as the resin. 7. The method for producing an artificial tooth according to claim 6, wherein after the light-curing resin is embedded to a desired thickness on the release surface side of the elastic impression type, a core material made of another material is charged into the remaining portion. 8. The method for producing an artificial tooth according to claim 7, wherein the core material is a solid that has been hardened in advance when the core material is charged, and the core material is pressed into an elastic impression mold containing a light-curable resin. 9. The method for producing an artificial tooth according to claim 8, wherein the light-curable resin is softened by heating when the core material is press-fitted. The method for manufacturing an artificial tooth according to any one of claims 5 to 9, wherein the elastic impression type is made of silicone rubber.

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