JP4514231B2 - Dentine ceramic and alumina ceramic teeth bonded with glass composition - Google Patents

Description

The present invention is a tooth used for a jaw and tooth model in which a student who aims to become a dentist experiences an intraoral work and practice treatment. More specifically, the present invention relates to a method for manufacturing a tooth used for experiencing formation of an abutment, formation of a cavity, and the like.

Teeth for a jaw and tooth model for intraoral treatment practice are often made of epoxy resin and melamine resin, and are widely used.
However, since epoxy resin and melamine resin have different cutting feelings, even when practicing abutment tooth formation and cavity formation, it is often embarrassed by the different cutting feeling and workability when working in the actual oral cavity. It was. Specifically, epoxy resins and melamine resins tend to be soft and increase cutting, and natural teeth tend to be hard to cut as expected because they are hard. Even in hard natural teeth, the dentin part is hard, but the enamel part is harder. As a result, there is a possibility that it will be sharply cut and the shape cannot be made well.

  As a result of a demand for a harder material, a composite type is commercially available. Even in composite type teeth, the dentin part and enamel part have the same cutting feeling, so the cutting feeling is different from natural teeth, and even if you practice abutment tooth formation and cavity formation, When working, it was often embarrassed by the different cutting feeling and workability. The easy-to-understand expression has a feeling of slipping, and the cutting feeling is very different from natural teeth.

In Japanese Utility Model Laid-Open No. 1-90068, Vickers hardness in which phlogopite crystal [NaMg3 (Si3AlO10) F2] and lithia / alumina / silica-based crystal (Li2O.Al2O3.2SiO2, Li2O.Al2O3.4SiO2) are simultaneously precipitated on the enamel layer. It is composed of glass and ceramics controlled to 350-450, and the root layer is added with white, red and yellow colorants in the polyol (main agent), and further mixed with an isocyanate prepolymer (curing agent) to form a silicone rubber base. It is injected into the mold under vacuum, hardened at room temperature and prepared in advance, and the dentin layer that is interposed between the enamel layer and the root layer is bonded with an opaque color. It shows that it is formed of a resin.

  However, when the enamel layer is composed of phlogopite crystals or lithia / alumina / silica crystals, the cutting feeling is too hard compared to natural teeth, so it is not durable and the dentin layer is an adhesive resin. Therefore, the cutting feeling of the adhesive was too soft, so it was not durable. Furthermore, there is a description that dentin is formed in the adhesive layer. It is shown that an enamel layer portion and a root layer portion are formed and bonded. It is recognized as dentin by a thick adhesive layer.

Japanese Patent Application Laid-Open No. 5-224591 shows that a tooth model having cutting ability very similar to natural teeth and suitable for dental education cutting practice is provided. As main constituent components, inorganic powder and cross-linked resin are contained in a weight ratio of 20% to 80% to 70% to 30%.

As the inorganic powder constituting the tooth model of the present invention, for example, alumina, zirconia, titania, silica and the like are introduced, and the inorganic powder is not limited to the above compounds, and various inorganic powders can be used.
However, since the cutting feeling is different from that of natural teeth, even when practicing abutment tooth formation and cavity formation, when working in the actual oral cavity, it was often embarrassed by the different cutting feeling and workability. Moreover, only an inorganic powder body is disclosed. In particular, it was not a tooth model that showed the difference in machinability between the enamel part and the dentin part.
Japanese Patent Laid-Open No. 5-216395 introduces the provision of a tooth model having a cutting ability very similar to that of natural teeth and suitable for dental education cutting practice and a method for manufacturing the same. Contains hydroxyapatite powder with a porosity of 40-80% and (meth) acrylic ester resin as a main component of the tooth model in a weight ratio of 20% to 80% to 50% to 50% It is what you are doing.
Conventional tooth models are not in a satisfactory state in terms of machinability. Therefore, although it has been shown that development of a tooth model similar to natural teeth in cutting ability is desired, it does not show a sufficient cutting feeling. In particular, it was not a tooth model that showed the difference in machinability between the enamel part and the dentin part.

JP-A-5-224591 provides a dental model that can be optimally used for a periodontal disease treatment practice of a dentist. As a constitution, at least the surface of the crown portion has a Knoop hardness of 70 or more, and at least the surface of the root portion has a Knoop hardness of 10 to 40.
In the text, there is a description that “it may be made of a material of any hardness, for example, metal, ceramics, resin, and may be a cavity from the viewpoint of the preparation method of the tooth model and economical viewpoint”. It has not been solved from the viewpoint of cutting feeling. In particular, it was not a tooth model that showed the difference in machinability between the enamel part and the dentin part.
In JP-A-5-241498, JP-A-5-241499, and JP-A-5-241500, there are descriptions of inorganic fillers and hydroxyapatite fillers. It has not yet been resolved. In particular, it was not a tooth model that showed the difference in machinability between the enamel part and the dentin part.

Japanese Patent Application Laid-Open No. 2004-94049 describes an invention for providing a dental training model tooth that enables accurate shape measurement using a laser beam.
In the specification, “as the material constituting the crown surface of the model tooth of the present invention, generally known materials can be used, for example, ceramics or other porcelain or acrylic, polystyrene, polycarbonate, etc. , Acrylonitrile styrene butadiene copolymer (ABS), polypropylene, polyethylene, polyester, and other thermoplastic resin materials, melamine, urea, unsaturated polyester, phenol, epoxy, and other thermosetting resin materials, and their main raw materials Glass fiber, carbon fiber, pulp, synthetic resin fiber and other organic and inorganic reinforcing fibers, talc, silica, mica, calcium carbonate, barium sulfate, alumina and other fillers, pigments, dyes and other colorants, or What added various additives, such as a weathering agent and an antistatic agent, can be used. Is described with, but there is no description of the preferred material, it was not intended to resolve the grinding feel.

Up to now, it was not a tooth model that could show the difference in machinability between the enamel part and the dentin part. Furthermore, there is no disclosure as a specific composition for realizing this cutting feeling, and no description is given of a manufacturing method thereof.
Although the jaw model has these problems, no research report has been found.

JP-A-5-241498 JP-A-5-241499, JP 5-241500 A JP 2004-94049 A Japanese Utility Model 1-90068

Although the conventional tooth for jaw model has a natural tooth form, it has a different cutting feeling. In order to experience the cutting feeling of natural teeth, some ideas such as cutting extracted teeth were seen. The extracted tooth is a material from the human body and animals, and there are problems with hygiene. There is a possibility of infection if hygiene is not adequately controlled, and practice must be freely prevented to prevent infection. . Moreover, since it is a natural living body, there is a problem of spoilage, and sufficient caution is required for storage.
There has been a demand for a method for experiencing the cutting feeling of a tooth without using a natural tooth. In particular, there is a demand for a change in the cutting feeling of the dentin portion from the enamel portion of the tooth. There was no way to do it.
As a result of research, it is necessary to use an inorganic fired body to give a cutting feel to natural teeth, but it is difficult to control the hardness of inorganic materials, so the enamel part is controlled while controlling these. And it was difficult to produce the dentin part.

In order to adjust the cutting feeling of the fired body, it is necessary to match the density, grain shape, and firing temperature of the fired body, but the shrinkage and thermal expansion differ during firing of the enamel part and the dentin part, cracking, peeling, Cracking, etc. occurs, and further, there is a gap between the dentin part and the enamel part, which may cause chipping during cutting, and the gap conveys a feeling different from the cutting feeling of natural teeth, and it did not endure use .
When the adhesive layer that bonds the enamel part and the dentin part is thick, a different cutting feeling is felt. As a result, the tooth model is greatly separated from the natural tooth.

The present invention relates to a tooth for a jaw and tooth model for therapeutic practice, comprising a dentin portion and an enamel portion, and after molding the dentin portion and the enamel portion using the CIM technique, a glass powder is formed between the dentin portion and the enamel portion. It is a tooth for a jaw and tooth model, wherein a dentin portion and an enamel portion are bonded together by degreasing and baking with the intercalation.

The present invention provides a tooth for a jaw and tooth model, wherein the maximum thickness of an interface between a dentin portion and an enamel portion formed by glass powder is 0.1 to 700 μm.
The present invention provides a tooth for a jaw and tooth model, wherein the glass powder is an aluminosilicate glass.
The present invention is a tooth for a jaw tooth model for treatment practice,
A step of kneading Al ₂ O ₃ powder having an average particle size of 1 to 8 μm with a binder, molding and baking with a molding machine, and Al ₂ O ₃ powder having an average particle size of 0.1 to 1.0 μm. A tooth for a jaw and tooth model, comprising the steps of kneading with a binder, molding with a molding machine, interposing a glass powder between the dentin portion and the enamel portion and firing.

The present invention is a tooth for a jaw and tooth model for treatment practice, wherein the dentin portion and the enamel portion are made of an inorganic powder fired body.
Furthermore, it is preferable that the thickness of the glass powder layer as an adhesive is 1 to 500 μm. More preferably, the thickness is 1 to 300 μm, and further preferably 1 to 200 μm. Furthermore, it is preferable to set it as 1-100 micrometers.
By reducing the adhesive thickness, cutting easily moves to the dentin portion of the sintered inorganic powder, and the cutting feeling with natural teeth is approximated.

The present invention relates to a jaw and tooth model characterized by injection molding using CIM technology, forming a dentin portion and an enamel portion through degreasing and baking processes, and bonding the dentin portion and the enamel portion using an adhesive. This is a method for producing dental teeth.

According to the method of the present invention, both the dentin part and the enamel part can obtain the same cutting feeling as that of the natural tooth, and the cutting feeling that shifts from the enamel part to the dentin part is close to that of the natural tooth. Practice cutting natural teeth easily.
Since the extracted tooth is a material from a living body and has a hygiene problem, a tooth that can be used safely without taking measures such as infection prevention and has a feeling similar to that of the extracted tooth has been demanded. In addition, there is a need for a material that does not require any sanitary management and is free from the risk of corruption.
By forming an abutment tooth and a cavity using the tooth of the present invention, a cutting feeling similar to that of a natural tooth can be experienced quickly, and the formation experience can be easily performed. Moreover, these formation techniques can be acquired quickly.
The jaw model tooth is a substitute for the hardest natural tooth in the human body, and a normal material feels soft at the time of cutting, while a cutting feeling similar to that of a natural tooth can be obtained. A cutting experience similar to that of cutting using diamond abrasives (using an air turbine) rotating at a high speed of 400000 revolutions per minute in the oral cavity is possible.

Since it is in contact with the cutting body that rotates at high speed in molding, compatibility with the jaw is important, and compatibility with enamel and dentin is also required, so it is necessary to use CIM (Ceramic Injection Mold) technology that can be molded precisely. preferable.
Furthermore, the shape of the crown of the tooth model is also important, and it is important that the ridges, fossa, and cusps are accurately expressed as the objective of abutment tooth formation and cavity formation. ing.
Since the tooth of the present invention can be white, ivory, milky white, and translucent, like a tooth, a more realistic cutting experience can be achieved. Preferred are white, ivory and milky white.
You can experience cutting natural tooth models without tasting the soft feeling of the adhesive. You can experience smooth cutting from enamel to dentin.
It can be easily cut from the molded enamel part to the dentin part while approximating the cutting feeling of natural teeth.

A tooth for a jaw and tooth model is a tooth used for simulating the practice of treatment in the oral cavity and practicing treatment using a jaw and tooth model in universities, etc., and the present invention cuts and forms teeth. It relates to the case used for In particular, the present invention relates to a tooth having cutting ability similar to that of a natural tooth and used for practicing cavity formation and abutment tooth formation.

The present invention consists in adhering a molded enamel part and a dentin part.
The glass powder used for the bonding of the present invention is preferably an aluminosilicate glass.
Adhesion required for the present invention is preferably that the enamel portion and the dentin portion are bonded together, and there is a portion that is not even bonded or that there are large bubbles that affect the cutting feeling. Absent.

The tooth composition of the present invention is preferably produced from ceramics. The composition of the tooth of the present invention is produced from ceramics or glass such as alumina, zirconia, silica, aluminum nitride, and silicon nitride. Moreover, it is preferable to produce by an alumina type and a zirconia type. Alumina-based and zirconia-based are that alumina or zirconia is 60% to 100%, preferably 80% to 100%, more preferably 95% to 100% of the fired body composition. In particular, the composition of alumina is 50% to 100%, preferably 70% to 100%, and more preferably 90% to 100%. The tooth composition is preferably molded from alumina powder.
Both the enamel part and the dentin part are preferably an inorganic powder fired body. To adjust the hardness of the enamel part and dentin part, there are methods such as roughening the grain size, increasing the voids, changing the material, changing the firing temperature, changing the mooring time, etc., but the most suitable method Is to change the particle size with the same composition.
The average particle size of the dentin portion is preferably 10 times or more than the average particle size of the enamel portion . When the average particle size of the enamel portion is 0.1 to 0.5 μm, the average particle size of the dentin portion is preferably set to 1.0 to 10.0 μm.
Although the firing temperature varies depending on the composition, the firing temperature is 800 to 1600 ° C, preferably 1000 to 1550 ° C, and preferably 1200 to 1500 ° C.

For forming the enamel part and the dentin part, it is preferable to use the CIM technique as a ceramic forming method.
It is also preferable that the enamel part and the dentin part are injection-molded using the CIM technology, degreased and fired through a glass powder between the enamel part and the dentin part, and fired. .

A female mold of the enamel part and dentin part of the tooth form was dug out, and a mold capable of injection-molding the target shape was produced. Since both the enamel part and the dentin part are shaped, and shrinkage occurs due to degreasing and firing, the part was largely calculated in advance to prepare a mold. The mold was adjusted for each material. The shrinkage of enamel was about 10% and the shrinkage of dentin was about 5%.
(Fired body 1)
Using 1 kg of alumina pellets for CIM as the raw material for the enamel part (Al ₂ O ₃ is 26%, SiO ₂ is 44%, average particle size is 0.25 μm, stearic acid is 30%), injection is made into a tooth-shaped mold. Molded to obtain an injection body 1-1.
Using 1kg of alumina pellets for CIM (26% Al ₂ O ₃ , 44% SiO ₂ , average particle size 3.0 μm, 30% stearic acid) as a raw material for dentin, injection into dental molds Molded to obtain an injection body 1-2.
The enamel portion was placed on the produced dentin portion with the following glass powder interposed therebetween, and the fired body 1 was obtained as degreasing and firing (1200 degrees, mooring time 10 minutes).

(Fired body 2)
Using 1 kg of alumina pellets for CIM (70% Al ₂ O ₃ , average particle size 0.3 μm, stearic acid 30%) as a raw material for the enamel part, injection molding is performed on a tooth-shaped mold. 1 was obtained.
Using 1 kg of alumina pellets for CIM (68% Al ₂ O ₃ , 2% SiO ₂ , average particle size 5.0 μm, 30% stearic acid) as a raw material for dentin, injection into a dental mold Molded to obtain an injection body 2-2.
The enamel portion was placed on the produced dentin portion with the following glass powder interposed therebetween, and the fired body 2 was obtained as degreasing and firing (1400 degrees, mooring time 15 minutes).
As the glass powder, fused silica having an average particle size of 0.5 μm and a maximum particle size of 2.0 μm was used.

(Fired body 3)
The enamel part and the dentin part of the fired bodies 1-1, 1-2, 2-1 and 2-2 obtained by producing in the same manner as in Examples 1 and 2 were fired using quartz glass powder, and the fired body. 3, 4 were obtained.

As an evaluation of the fired bodies 1 to 4, a cutting test and an adhesion state test were performed.
In the cutting test, it was confirmed that all of the fired bodies 1 to 4 had a good cutting feeling.
In the adhesion state test, the fired bodies 1 to 4 were sliced with a diamond disk at intervals of about 5 mm to confirm the adhesion state. It was confirmed that all the fired bodies 1 to 3 were in a good adhesion state.

Claims (1)

A tooth for a jaw and tooth model for treatment practice, comprising a dentin portion, an enamel portion and a glass powder layer formed between the dentin portion and the enamel portion,
The dentin part and enamel part are made of an inorganic powder fired body, the glass powder layer is made of fused silica or quartz glass,
The average particle diameter of the inorganic powder enamel portion is the 0.1 to 0.5 [mu] m, an average particle diameter of the inorganic powder dentin portion is 1.0～10.0Myuemu, the average particle diameter of the dentin portion to the average particle diameter of the enamel portion More than 10 times,
A tooth for a jaw and tooth model, wherein the glass powder layer has a thickness of 1 to 500 µm.