JPH0549650A - Production of dental prosthetic appliance - Google Patents

Abstract

PURPOSE:To provide the process for production of the dental prosthetic appli ance which can produce the dental prosthetic appliance having an excellent aesthetic property and high mechanical strength. CONSTITUTION:A core material 12 formed by casting and molding castable ceramics in accordance with the conventional method, then subjecting the molding to a crystallization treatment by heating the molding at 920 deg.C is disposed on an abutment tooth pattern 11. A porcelain mixture 13 prepd. by mixing porcelain 'Bitadule-N(R)' produced by Bita Co., porcelain 'Duceram(R)' correction powder (K) produced by Ducera Co., and low fusing graze material 'Ceracom Fine Grating Stain(R)' produced by Ceracom Co., at 7:2:1 weight ratio is then built up. After this mixture is cried for minutes at 600 deg.C, the mixture is heated up to 905 deg.C at 50 deg.C ratio per minute under a reduced pressure (760mmHg). The molding is then held for 30 minutes at 905 deg.C and is slowly cooled in the atm., by which the dental prosthetic appliance 10 is obtd.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a method for manufacturing a dental prosthesis.

[0002]

2. Description of the Related Art Conventionally, a dental prosthesis used for repairing an affected tooth or a missing tooth is manufactured, for example, as follows. First, as shown in FIG. 2, an abutment tooth model 21 is produced based on an impression taken from an abutment tooth produced by cutting an affected tooth. Next, on the abutment tooth model 21, a metal core material 22 having a shape covering the abutment tooth is manufactured. Then, on the core material 22, the core material 2
Opaque porcelain 23 for shielding the metallic color of 2, and dentine-like porcelain 24 corresponding to the dentine of natural teeth,
An enamel-like porcelain material 25 corresponding to the enamel of natural teeth and a transparent porcelain material (translucent) 26 for drawing out transparency are successively built up. Then, the porcelain is baked to obtain the dental prosthesis 20.

In the method of manufacturing the dental prosthesis 20 described above, castable ceramics formed by casting glass ceramics is also used in place of the metal core material.

[0004]

In the above-described method for manufacturing a dental prosthesis, when porcelain is baked, adjacent porcelain particles are bonded and integrated. However, porosity is likely to occur between the bonded porcelain particles. Therefore, the mechanical strength and wear resistance of the completed dental prosthesis are significantly reduced.

When castable ceramics are used as the core material, the transparency of the castable ceramics is adjusted in order to improve the aesthetics of the core material. Since the transparency of the castable ceramics varies depending on the glassy matrix and the ratio of the crystalline material, the transparency of the castable ceramics can be adjusted by heat-treating the castable ceramics at a predetermined temperature. However, when the porcelain is laid on the core material having low crystallinity of the castable ceramic and then the porcelain is baked, the crystallization of the castable ceramic further proceeds. For this reason, the color and transparency of the castable ceramics change, and the castable ceramics further contracts. As a result, there are problems that it is difficult to adjust the color tone of the dental prosthesis, and voids are generated at the interface between the castable ceramics and the porcelain, which deteriorates the compatibility between the castable ceramics and the porcelain.

The present invention has been made in view of the above points, and provides a method for producing a dental prosthesis capable of producing a dental prosthesis which is more aesthetically pleasing and has high mechanical strength. Is.

[0007]

SUMMARY OF THE INVENTION The present invention provides a method for manufacturing a dental prosthesis, characterized in that a mixture of porcelain and glaze material is built up on a core material and then baked at a predetermined temperature. .. Here, as the glaze material, it is preferable to use a low melting glaze material having a melting temperature of 800 ° C. or lower.

Castable ceramics and metals can be used as the core material. When the core material is castable ceramics, it is preferable to crystallize the castable ceramics at a temperature higher than the temperature at which the mixture of porcelain and glaze material is baked.

[0009]

According to the method for manufacturing a dental prosthesis of the present invention, since the vitreous glaze material is mixed with the porcelain, pores generated between the porcelain particles bonded when the porcelain is baked. Are filled with glaze material. Thereby, the mechanical strength of the surface of the dental prosthesis can be improved.

When castable ceramics is used as the core material, the castable ceramics are
The crystallization treatment is performed at a temperature higher than the temperature at which the mixture of porcelain and glaze is baked, and the castable ceramics are crystallized until the crystallization no longer progresses at the temperature at which the mixture of porcelain and glaze is baked. This can prevent the crystallinity of the castable ceramics from changing when baking the mixture of porcelain and glaze.

[0011]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a longitudinal sectional view showing an example of a dental prosthesis manufactured according to the method for manufacturing a dental prosthesis of the present invention.

As shown in FIG. 1, castable ceramics (hereinafter referred to as OCC) H manufactured by Olympus Optical Co., Ltd.
After casting -13 (the darkest material in OCC) according to a conventional method, the core material 12 which is heated at 920 ° C. and crystallized is arranged on the abutment model 11. Next, on the core material 12, Vita porcelain Vitadur made by Vita-
N (trade name; VITADUR-N), Ducera (Duc
era) porcelain Duceram modified powder (K) and low-melting glaze material Seramco (trade name Ceramco) fine grain stain (FINEGRAIN SATAIN) manufactured by Seramco in a ratio of 7: 2: 1 by weight. Build up the porcelain mixture 13 mixed in. Next, after drying at 600 ° C. for 5 minutes, it was dried under reduced pressure (76
The temperature was raised to 905 ° C at a rate of 50 ° C / min at 0 mmHg). Then, the temperature was maintained at 905 ° C. for 30 minutes and then gradually cooled in the atmosphere to obtain the dental prosthesis 10 of Example 1.

Next, OCCH-13 is cast and molded according to a conventional method, and the core material which is heated at 920 ° C. and crystallized is placed on the abutment tooth model. Next, on the core material, a porcelain material made of Vita porcelain Vitadur-N alone is built up. Next, after drying at 600 ° C. for 5 minutes, the temperature was raised to 960 ° C. at a rate of 50 ° C./min under reduced pressure (760 mmHg). Then, after holding it at 960 ° C. for 30 minutes, it was gradually cooled in the atmosphere to obtain a dental prosthesis of Comparative Example 1. The following tests were performed on the dental prostheses of Example 1 and Comparative Example 1 manufactured in this way.

First, the dental prostheses of Example 1 and Comparative Example 1 were observed under a stereoscopic microscope under the same conditions.
No cracks were observed in the porcelain mixture 13 of the dental prosthesis of Example 1. On the other hand, in the dental prosthesis of Comparative Example 1, fine cracks were observed in the porcelain material such as the margin after being gradually cooled in the atmosphere.

Further, when the built-up portion was cut and the cut surface was observed with a stereoscopic microscope, the dental prosthesis of Example 1 showed that
The glaze material invaded and filled the pores between the bonded porcelain particles, and the pores were few. However, in the dental prosthesis of Comparative Example 1, many pores were recognized.

Next, when the dental prostheses of Example 1 and Comparative Example 1 were ground using carborundum points, the porcelain mixture 13 of the dental prosthesis of Example 1 was sticky and hard. .. On the other hand, the porcelain material of the dental prosthesis of Comparative Example 1 had no stickiness, was soft, and was shaved.

Further, for the dental prostheses of Example 1 and Comparative Example 1, instead of the toothbrush abrasion test, alumina white paint was attached to the engine to clarify the difference in abrasion resistance. The grinding amount of each dental prosthesis was compared while keeping the rotation time constant. The cutting was performed using a dental micromotor C2 manufactured by Tegusa Co., Ltd. at a rotation speed of 10,000 rpm for 1 minute, and then the cutting surface was observed with a stereoscopic microscope with a magnification of 16 times.

As a result, it was confirmed that the dental prosthesis of Comparative Example 1 had a larger amount of cutting than the dental prosthesis of Example 1, and Example 1 had a denser structure. It was confirmed that the wear resistance was excellent.

From the above test results, the dental prosthesis of Example 1 in which the porcelain mixture in which the porcelain and the glaze material were mixed was built up more than the dental prosthesis of Comparative Example 1 in which only the porcelain was built up. It was confirmed that there were few pores and the mechanical strength and abrasion resistance were excellent.

Next, except that the OCC crystallization temperature of the core material 12 was set to 880 ° C., which was lower than the baking temperature (905 ° C.) of the porcelain mixture, and the crystallization treatment was performed, the dentistry of Example 1 The dental prosthesis of Comparative Example 2 manufactured by the same method using the same material as the dental prosthesis was prototyped, and the color tone of the porcelain was compared with that of the dental prosthesis of Example 1. As a result, Example 1
In the dental prosthesis of No. 1, it was possible to obtain the initially planned color tone, but in the dental prosthesis of Comparative Example 1, when the porcelain mixture was baked, the crystallization of OCC constituting the core material proceeded. As a result, the color of the core material changed subtly, and the intended color tone could not be obtained. From this result, it was confirmed that the dental prosthesis of Example 1 which was subjected to the crystallization treatment at 920 ° C. higher than the baking temperature of the porcelain mixture was more excellent in color reproducibility.

Further, in the dental prosthesis of Example 1 and the dental prosthesis of Comparative Example 2, the shrinkage rate due to the crystallization of OCC of the core material was measured, and it was found that 0CC was crystallized at 920 ° C. The dental prosthesis of No. 2 was about 0.62%, and the dental prosthesis of Comparative Example 2 in which 0CC was crystallized at 880 ° C. was about 0.56%. From this result, the dental prosthesis of Example 1 that was subjected to the crystallization treatment at 920 ° C., which is higher than the baking temperature of the porcelain mixture, had a larger shrinkage rate due to crystallization, and already contracted when the porcelain mixture was baked. It is difficult to shrink further. As a result, it was confirmed that the dental prosthesis of the example had excellent compatibility between the core material and the porcelain mixture at the time of completion.

In this embodiment, for convenience, the core material 12 is used.
Although the dental prosthesis integrally formed with the porcelain mixture 13 laid on the above has been described, the present invention is not limited to this, and dentin porcelain, enamel porcelain and the like are sequentially formed. It can also be applied to the production of laminated dental prostheses.

[0023]

As described above, according to the method for producing a dental prosthesis of the present invention, by mixing the porcelain with the glaze material, the pores generated between the porcelain particles bonded by baking are formed. Can be filled with a glaze material. Thereby, the mechanical strength and wear resistance of the dental prosthesis can be improved. In addition, when castable ceramics are used for the core material, crystallization is performed when baking the mixture of porcelain and glaze by performing crystallization treatment at a temperature higher than the temperature at which the mixture of porcelain and glaze is baked. Of the dental prosthesis and the compatibility of the core material with the built-up porcelain and glaze material can be improved. is there.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing an example of a dental prosthesis manufactured according to the method for manufacturing a dental prosthesis of the present invention.

FIG. 2 is a longitudinal sectional view showing an example of a dental prosthesis manufactured according to a conventional method for manufacturing a dental prosthesis.

[Explanation of symbols]

10 ... Dental prosthesis, 11 ... Abutment tooth model, 12 ... Core material, 13 ... Porcelain mixture.

Claims (4)

[Claims] 1. A method for producing a dental prosthesis, which comprises laying a mixture of a porcelain material and a glaze material on a core material and then baking the mixture at a predetermined temperature. 2. The method for manufacturing a dental prosthesis according to claim 1, wherein the core material is castable ceramics. 3. The production of a dental prosthesis according to claim 2, wherein the castable ceramic constituting the core material is subjected to a crystallization treatment at a temperature higher than a temperature at which the mixture of the porcelain and the glaze material is baked. Method. 4. The method for manufacturing a dental prosthesis according to claim 1, wherein the core material is a metal.