JPH01218444A - Heat resistant dowel pin for dental technician - Google Patents

Abstract

PURPOSE:To execute the recover of a contact with adjoining teeth as it is on a model and an engagement adjustment with an opposite tooth in setting a porcelain recovering material along with a fire resistance model to an engaging device, and to execute a technician operation with a high accuracy by composing a pin of a heat resistance alloy or ceramics not to be melted and deformed at least 1000 deg.C. CONSTITUTION:A downel pin is manufactured of the heat resistant alloy or ceramics not to be melted and deformed at 1000 deg.C at which a fire resistance model material is baked in an electric furnace for a dental technician. As to a heat resistance dowel pin for a dental technician whose material is the ceramic, it can be manufactured by a dry pressure forming and an injection forming. For example, at the time of the dry pressure forming, powders, in which ceramics powders to be used are made into the granules of the degree of 40-140micron by a binder such as a methylcellulose, are press-pressure- formed by the automatic press of the degree from 2t to 10t, and a raw mold is obtained. When the material is a heat resistant metal, the manufacture can be executed by a machine processing with a milling machine, a precision casting method with a lost wax method, etc.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a heat-resistant dowel pin for dental technology used in a removable model to be manufactured for making a porcelain crown such as a porcelain jacket crown, which is a dental prosthesis. It is related to.

[Conventional technology]

To create a porcelain crown such as a porcelain jacket crown, which is a conventional dental prosthesis.

The desired tooth that has been previously treated by a dentist, such as grinding.
A negative mold is taken by pressing an impression material such as alginate on either the teeth in the upper or lower jaw that oppose these teeth, or the entire teeth in the upper and lower jaws. A gypsum mud for modeling, such as anhydrite or superhard gypsum, is poured into this negative mold, and the plaster for modeling is taken out after hardening to create a working model.

This working model is set in a model articulator, and a porcelain crown such as a porcelain jacket crown is built up on the working model. However, with this working model as it is, the gap between the target tooth and the adjacent tooth is narrow, making it difficult to insert working machines and tools and making it difficult to perform precise technical work.

Therefore, the tooth model of the part of the tooth on which a porcelain crown such as a porcelain jacket crown is to be applied is divided and removed from the entire model, and after performing technical work, it is returned to the original model where the tooth is adjacent to the adjacent tooth. A method has been proposed that thoroughly checks the relationship with the teeth and the occlusal relationship with the opposing teeth. To carry out this method, a split removable model method using dental dowel pins is used.

That is, first, alginate is applied to either multiple teeth, including the target tooth, which the dentist has previously performed treatment such as grinding, the teeth in the upper or lower jaw that oppose these teeth, or the teeth in the upper and lower jaws as a whole. A negative mold is obtained by pressing impression materials such as, etc., and the dental technician uses a holding device or supports the desired tooth part in the negative mold with a dowel pin for the dental technician to hold the negative mold. Pour plaster mud for a primary model such as anhydrite or superhard gypsum into the mold until the head of a dowel pin for dental technology is buried, and after this plaster for the next model hardens, only the tooth part that is to be separated and removable is poured. A separating agent is applied to prevent the plaster mud for the secondary model and the plaster for the primary model from adhering to each other, which will be cast next, and then the gypsum mud for the secondary model is poured into the dental laboratory. The feet of the dowel pins are immersed in plaster mud for secondary models and removed from the negative mold after hardening.

After that, mark the boundary between the tooth part where the dental technique will be applied and the adjacent tooth where the dowel pin for the dental technique is placed. The foot part of the dowel pin for dental technology is cut with a jig saw until the tooth reaches the hardened secondary model plaster, and the tooth part to be applied with dental technology with the dowel pin for dental technology planted is pulled out at right angles to the hardened secondary model plaster. Next, a removable model part of only the tooth part to be repaired is easily extracted from the model plaster together with a dowel pin for dental technicians. Therefore, platinum foil was pressed against the part of the extracted removable model part where the porcelain crown was to be built up, and after the porcelain was built up on top of it and the shape was adjusted, the porcelain built up from the removable model part was whitened. The entire gold leaf is removed, placed on a firing table, and fired in a vacuum in an electric furnace for technicians. The porcelain crown, such as a porcelain jacket crown, which has been fired in this way is returned to the built-up part of the original removable model part, and the removable model part is further positioned in a predetermined position on the secondary model plaster using the dowel pin for dental technology as a guide. Being forced to
After checking the relationship with adjacent teeth and occlusal relationship with opposing teeth, we add porcelain to areas where the build-up is insufficient, and remove excessive build-up, respectively, and fire it again to create porcelain jacket crowns. The crown is completed.

Conventional dowel pins for dental techniques used in this way can be broadly divided into two types, synthetic resin and alloy, depending on the material. For example, synthetic resins include Teflon resin, polybutylene terephthalate resin, and polybutylene terephthalate resin. The majority are made of thermoplastic resins such as polyethylene resin, polystyrene resin, polyacetal resin, polyvinyl chloride resin, and polycarbonate resin. In addition, most of the alloys are made of brass-based alloys, and the shape consists of a head and a foot, and the head has a net-like part to which plaster for modeling can be fixed. The foot is conical or plate-shaped, and in the case of a conical shape, it rotates relative to the secondary model plaster to change the positional relationship with the adjacent teeth. Generally, it is a flat surface with one side cut to prevent it from being damaged.

[Problem to be solved by the invention]

However, in recent years, when creating porcelain crowns, an impression is taken using the same method as described above, and a fire-resistant modeling material mud such as phosphate-based or ethyl silicate-based material that can withstand high temperatures is injected into the impression. The cured green model material is removed from the impression and air-baked to obtain a model that does not easily deform. Porcelain mud is directly applied to the tooth area to be repaired on this model, and the entire model is placed in a technical electric furnace again. The direct build-up method, in which the porcelain crown is fired, was developed as a preferred method because the porcelain crowns produced do not deform during firing.

■ However, if you try to create a porcelain crown by building up porcelain mud directly on the model and firing the entire removable model in an electric furnace for technicians without removing it from the model, it will be difficult to create a porcelain crown using conventional plaster-based model materials or conventional brass or plastic. A removable model using dowel pins for dental technology cannot be used because the plastic will burn out and the brass will melt or deform at high temperatures such as dry firing of fireproof modeling mud or firing of porcelain.

■ As a result, when attempting to create a porcelain crown using the traditional technique of impenetrable plaster-based models, the process of press-fitting platinum foil is difficult to create, and traditional dental techniques made of brass or plastic are difficult to create. Even in the case of a removable model made of plaster-based model material using dowel pins, it is difficult to remove the porcelain crown from the model without deforming it while it is still built up on platinum foil. There are only a very limited number of engineers who can carry out the process, and even those skilled engineers have difficulty obtaining sufficient accuracy in terms of compatibility and the like when making a porcelain crown using platinum foil.

■ Furthermore, even if you try to build up and fire a porcelain crown such as a porcelain jacket crown directly on a refractory model, the model of the tooth to be restored cannot be removed because the dowel pins do not currently have heat resistance. Either there is no model, or even if it can be divided, there is no guide such as a dowel pin, so the divided model parts cannot be returned to the correct position, making it impossible to perform precise dental techniques.

■ As mentioned above, the working model cannot be divided, so for example, when building a porcelain crown such as a porcelain jacket crown, you want to make it larger in anticipation of the shrinkage of the porcelain during firing, but the adjacent teeth on the working model get in the way, and the working model Although it is possible to build up porcelain by removing the upper adjacent teeth, since the working model of the adjacent teeth has been shaved off, it is difficult and impractical to adjust the contact relationship with the adjacent teeth. It is also difficult to adjust the occlusion between the teeth.

There were various problems that were difficult to solve.

[Means to solve the problem]

The present invention aims to solve the problem that the conventional techniques described above were not able to satisfactorily produce porcelain crowns such as porcelain jacket crowns, which are dental prostheses. As a result, this heat-resistant dental technique is used in dental technology, in which porcelain mud is directly deposited on a fire-resistant model and fired in a technical firing furnace. By using dowel pins, it is possible to make the refractory model removable, and when fabricating not only porcelain jacket crowns but also dental porcelain restorations such as porcelain laminate veneers and Beaucelain onlays, you can attach adjacent teeth directly to the model. This makes it possible to perform highly accurate technical operations such as repairing contacts between teeth and adjusting occlusion with opposing teeth by setting a fireproof model and porcelain restoration in an articulator.

That is, in order to solve the above-mentioned problem and achieve the object, the present invention uses at least 10 materials for the dowel pin for dental technology.
It is characterized by being made of a heat-resistant alloy or ceramic that does not deform or melt when repeatedly heated up to 00°C, preferably 1200°C.

The shape of an embodiment of the heat-resistant dowel pin for dental technology according to the present invention having such heat resistance will be briefly explained with reference to the drawings.

FIG. 1 is an enlarged front view of one embodiment of the heat-resistant dowel pin for dental technology according to the present invention, FIG. 2 is a side view of the same, FIG. 3 is a plan view of the same, FIG. 4 is an open bottom view, and FIG. 6 is an enlarged front view of another embodiment of the heat-resistant dowel pin for dental technology according to the present invention, FIG. 7 is a side view of the same, and FIG. 8 is an open plan view. , FIG. 9 is a bottom view of the same.

In the drawing, 1 is the head of a heat-resistant dowel pin for dental technology, 2
are the same legs, and the head 1 has protrusions and screw-shaped parts (ring-shaped protrusions in Fig. 1, and only the two opposing sides in Fig. 6) so that the fireproof model material can be fixed. The foot part 2 has a conical shape (Fig. 1) or a pyramid shape, and rotates with respect to the secondary model material to adjust the positional relationship with the adjacent teeth. It is designed not to change. One surface of the head 1 and the foot 2 is flat. 3 is a primary refractory model material 3 in which the head 1 of a heat-resistant dowel pin for dental technology is embedded; a porcelain crown built up on the primary refractory model material 3;

[Effect]

The heat-resistant dowel pin for dental technology according to the present invention is made of a heat-resistant alloy or ceramic that does not melt or deform at at least 1000°C, which is the temperature at which a refractory model material is fired in an electric furnace for dental technology, as described above. and
As a result, it acts like a law.

■ As the ceramics constituting the heat-resistant dowel pin for dental technology, one or more selected from the group of alumina, zirconia, forsrite, mullite, cordierite, silicon carbide, and silicon nitride are used, or a heat-resistant alloy is used. By using a nickel-chromium alloy, a heat-resistant stainless steel alloy, a cobalt-chromium alloy, or a titanium-based alloy as the material, it is possible to prevent deformation or melting at at least 1000°C, preferably 1200°C, which is the firing temperature used in dental technology. Alternatively, it is possible to impart heat resistance that will not cause burnout.

■ By creating a fire-resistant splittable model using a heat-resistant dowel pin for dental technology made of the above materials and a phosphate-based or ethyl silicate-based fire-resistant model material,
It is now possible to separate and removable the necessary parts, and by directly applying porcelain mud to the removable model, it is possible to fire only the removable parts of the model in a technical firing furnace without removing it from the model. This makes the technique of making porcelain crowns more common, as it eliminates the need to use techniques that use platinum foil, and it also greatly improves the accuracy of compatibility and other aspects.

■ By using a heat-resistant dowel pin for dental technology, it can be used as an effective guide when placing the one-piece model in its original position, making it possible to precisely reproduce the position.

■ In the case of porcelain crowns that come into contact with adjacent teeth, such as porcelain jacket crowns and Beaucelain laminate veneers, anyone can easily adjust the occlusion with the opposing teeth and the contact relationship with the adjacent teeth by removable in one section. It can be done quickly and easily.

The present invention will be explained in more detail below with reference to Examples. Note that these examples are merely illustrative, and the present invention is not limited thereto.

〔Example〕

In each embodiment, the heat-resistant dowel pin for dental technology made of ceramic can be manufactured by dry pressure molding or injection molding, which are common ceramic molding methods. For example, in the case of dry pressure molding, the ceramic powder to be used is made into granules of about 40 to 100 microns with a binder such as dextrin, starch, acrylate, polyvinyl alcohol, methylcellulose, etc. Press pressure molding is performed using a press to obtain a green mold. In addition, in the case of injection molding, ceramic powder used and phenol resin as a binder,
Thermosetting resins such as urea resin, melamine resin, polyester resin, thermoplastic resins such as polyethylene resin, polyvinyl chloride resin, polyacrylic resin, polystyrene resin,
A plasticizer such as butyl phthanate, a solvent such as methyl ethyl ketone, methyl alcohol, n-butyl alcohol, and a dispersant such as cod liver oil are mixed and injection molded into a heated mold using a plunger type injection molding machine. After thoroughly incinerating the organic binder, etc. used for molding, the green mold molded as described above is fired under firing conditions suitable for each material to obtain a product.

If the material is a heat-resistant metal, it can be manufactured by machining using a lathe or milling machine, precision casting using a lost wax method, or the like.

The heat resistance test was conducted using fireproof model mud with inner dimensions of 10ms x 10m5.
Pour some of it into an X10 silicone mold, plant the head of this heat-resistant dental tech dowel pin there, apply a separating agent to the hardened fireproof model material, and then inject secondary fireproof model mud. After curing, the sample was removed from the silicone mold, the head and bottom were separated, and only the head was heated in a dental electric furnace from 700°C to 1000°C at a rate of 50°C/min.
5. Moor at 000℃ for 10 minutes and let cool to room temperature.
After repeating the test several times, the dowel pin for dental technology was visually inspected for melting and reaction with the fireproof model material. In addition, by using the heat-resistant dowel pin for dental technology as a guide, the deformation of the dowel pin for dental technology was examined and evaluated to see if it could be stored in its original position at the bottom. .

The results are shown in the table below.

The following margin [Effects of the invention] As is clear from the table, when the composition of the dowel pin for dental technology is conventional plastic and brass (Comparative Examples 1 and 2.3)
In this case, porcelain for dental technology cannot be used in cases where porcelain is directly built up on a model and fired using the split portable model method using fire-resistant model materials, as it will melt or burn out at high temperatures such as when fired at high temperatures. understood.

On the other hand, when the composition of the dowel pin for dental technology is made of a single ceramic as in the present invention (Examples 1 and 2)
, 3, 4, 5, 6.7), when two types of ceramics were mixed (Example 8.9).

In the case of heat-resistant alloy (Example 10.11.12.13
), it does not melt, burn out, or deform even at the high temperatures used to fire porcelain for dental technology, so it can be used to build up porcelain directly onto a model and fire it using the split removable model method using fire-resistant model materials. □It turns out that it is possible to do this.

As detailed above, the heat-resistant dowel pin for dental techniques according to the present invention is made of a heat-resistant alloy or ceramic material that does not melt, burn out, or deform under high temperatures such as those used in firing porcelain. By doing.

(2) It is possible to impart heat resistance that will not burn out, melt, or deform at the firing temperature of 1000°C, preferably 1200°C, which is the firing temperature used in dental technology.

■ By creating a fire-resistant split-removable model using a heat-resistant dowel pin for dental technology made of the above materials and fire-resistant model material, it becomes possible to separate and remove the necessary parts, making it possible to By applying porcelain mud directly to the model, it is now possible to fire only the permeable parts of the model without removing it from the model in a technical kiln.
There is no need to use the technique using platinum leaf, and the technique becomes more common.

■ A heat-resistant dowel pin for dental technology can be used as an effective guide when placing the split model in its original position, making it possible to precisely reproduce the position.

■ In the case of porcelain crowns that come into contact with adjacent teeth, such as porcelain jacket crowns and porcelain laminate veneers, the model can be separated and removed to adjust the occlusion with the opposing teeth and the contact relationship with the adjacent teeth. becomes possible.

Various advantages can be obtained.

As described above, the heat-resistant dowel pin for dental techniques according to the present invention can be used to create porcelain crowns such as porcelain jacket crowns and porcelain laminate veneers by directly building and firing porcelain on a model using a removable model method using fire-resistant model materials. It is an extremely important tool that contributes to the development of the dental field, making it possible to carry out comfortable technical work.

[Brief explanation of the drawing]

FIG. 1 is an enlarged front view of one embodiment of the heat-resistant dowel pin for dental technology according to the present invention, FIG. 2 is a side view of the same, FIG. 3 is an open plan view, FIG. 4 is a bottom view of the same, and FIG. 6 is an enlarged front view of another embodiment of the heat-resistant dowel pin for dental technology according to the present invention, FIG. 7 is a side view of the same, and FIG. 8 is a plan view of the same. , FIG. 9 is a bottom view of the same. In the drawing 1...Head part 2 of a heat-resistant dowel pin for dental technology...
・・Foot part 3 of heat-resistant dental laboratory dowel pin・・・・−
Next refractory model material 4...Porcelain crown Patent applicant: Toto Kogyo Co., Ltd.

Claims (1)

[Claims] 1. A heat-resistant dental material made of a heat-resistant alloy or ceramic that does not melt or deform at a temperature of at least 1000°C in which a fire-resistant model material is fired in an electric furnace for dental technology. Dowel pin for technicians. 2. The heat-resistant dowel pin for dental technology according to claim 1, wherein the ceramic is one or more selected from the group of alumina, zirconia, falsulite, mullite, cordierite, silicon carbide, and silicon nitride. 3. The heat-resistant dowel pin for dental technology according to claim 1, wherein the heat-resistant alloy is made of any one of a nickel-chromium alloy, a heat-resistant stainless steel alloy, a cobalt-chromium alloy, and a titanium-based alloy.