JPS6171042A - Treatment of calcium phosphate type crystallized glass dental material - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a method for improving the durability of artificial dental materials made of calcium phosphate crystallized glass.

(Prior art and its problems) As a dental material for dentures, tooth roots, crowns, inlays, bridges, etc., and biomedical ceramic materials such as surgical artificial bone materials,
For example, in Japanese Patent Publication No. 55-11625, Can
2a - 57wtL P2Os Glass with a composition of 72 - 43wt%, or this with 10wt% or less of AL7Q3
, SiO, , or B2O3 is melted, formed, and then heat-treated to crystallize it to a crystallinity of 20 or more. Calcium phosphate-based crystallized glass has been proposed.

This calcium phosphate crystallized glass has a composition very similar to that of natural teeth or natural aggregates, and its physical, chemical, and mechanical properties are also close to those of natural teeth or natural aggregates, and it also has a close relationship with living organisms. It has a good fit, and can be manufactured through a simple process of gluing the raw material powder, so precision machining is not required even for complex shapes.
It is expected to have superior properties and high mass productivity compared to conventional metal materials and ceramic ceramic materials as biomedical ceramic materials such as dental materials and surgical artificial aggregates. Furthermore, regarding the manufacturing method of calcium phosphate-based crystallized glass suitable for dental crown restoration materials, please refer to Japanese Patent Application Laid-open No. 141508/1983, r Com
communications of American C
It has been proposed in eramicSocietyJ C-101 (In2).

However, artificial dental materials made of such calcium phosphate-based crystallized glass have insufficient water resistance, acid resistance, etc., and are insufficient in durability.

(Means for Solving the Problems and Summary of the Invention) The present invention solves the above-mentioned drawbacks and also provides a calcium phosphate-based crystallized moth that can dramatically suppress the progression of dental caries.
It was invented as a result of examination and research for the purpose of providing artificial dental materials, and its gist is that it is a calcium phosphate crystallization system in which the atomic ratio of calcium to Li is Ca/P of 0.35 to 0.7. The surface of a dental material made of glass is treated with a solution containing a fluorine compound, and then treated with a solution containing a rare earth metal compound to form a fluoride rare earth metal compound layer on the surface. The present invention relates to a method for treating a calcium phosphate-based crystallized glass dental material, which is characterized by:

(Invention, composition of invention) The present invention will be explained in more detail below.

The glass composition used in the present invention is composed of calcium metaphosphate (CaO/P2O5), which has a chain structure both in the glass state and in the crystalline state, and has an appropriate melting temperature and appropriate melt viscosity for easy casting. The atomic ratio Ca/P of calcium and phosphorus is in the range of 0.35 to 0.7(1) (Dmo(1), i.e. t, C
aO28~38WT$, P2Os 72~84wt%
Is the composition of 'optimal'? Ca'/P ratio is 0.7
If it exceeds this, it becomes difficult to vitrify, which is not preferable, and
If it is lower than 0.35, the phosphorus component will be excessive and the water resistance will decrease, which is not preferable. Calcium phosphate glass with this composition is based on the composition of natural teeth and aggregates, that is, it is mainly composed of high-quality lucium phosphate crystals and is amorphous, and has an atomic ratio of Ca' /P is approximately 1.75
It approximates the ml composition in the range of ~2.0, and has good affinity with living organisms. With the glass having such a composition, an artificial dental material can be obtained by a simple process of melting the glass raw material powder into a glass shape, pouring it into a mold, and then crystallizing it. In the present invention, Al is added to the calcium phosphate crystallized glass having the above composition in order to improve the water resistance of the glass and to promote uniform crystallization in the crystallization process.
2O31zr+32"□.

TI"02, 'SnQ., 'Y2O3, etc. can be added in an amount of 0.5 to 5 mol2 to calcium phosphate crystalline glass. The addition ratio of additive components such as Al2O3 makes melting and vitrification of 5s difficult. undesirable, and
If it is lower than 045 mole 2, the effect of improving water resistance will be lowered, which is not preferable.

In producing the calcium phosphate crystallized glass of the present invention, a calcium compound as a raw material, calcium phosphate, and an aluminum compound as the above-mentioned additive are prepared and mixed, and if necessary, The slurry is made into a slurry, dried, crushed, and then calcined to prepare a powder mainly composed of calcium phosphate, which is then melted. When producing living body parts from this calcium phosphate crystalline glass, the melt is poured into a mold to form a defined shape, and then crystallized to obtain the final product.

The above-mentioned calcium compounds include calcium carbonate,
Calcium oxide is the most typical, but other forms include finely glazed calcium oxide, calcium oxalate, and inorganic and organic salts of calcium acetate. As the phosphorus compound, glues such as orthophosphoric acid, or ammonium salts of these phosphoric acids are used.

In addition, calcium salts of phosphoric acids such as calcium monononate, calcium hydrogen phosphate, calcium dihydrogen phosphate, calcium pyrophosphate, acidic calcium phosphate, calcium polyphosphates, and hydroxyapatite may be used alone or in combination with other calcium compounds or phosphorus compounds. It can also be used in combination with

Further, as the aluminum compound, aluminum hydroxide, aluminum oxide, aluminum nitrate, ammonium carbonate, aluminum chloride, aluminum phosphate, etc. are used.

For example, in producing the above-mentioned calcium phosphate-based crystallized glass dental material, 28 to 42 mo1% of finely pulverized CaCO3 and 5 to 73 moI of 113PO4 are used.
%, powdered (7) AI(OH)3 0.5-5 mol$
Add water to this slurry, dry it, and crush it to prepare a powder mainly composed of calcium phosphate. This is fired at 200 to 800°C for 1 to 10 hours to form a glass base ÷ I mean 1. Next, put the required amount of this glass raw material into a platinum crucible and heat at 900~+500'O for 5 minutes~1
After heating and melting for 0 hours and vitrifying homogeneously, for example, the caulking wax is incinerated based on the lost wax method,
The molten glass is kept at 500 to 800°C and cast into a lost wax mold in the investment material. This molded body is taken out together with the investment material or from the investment material and subjected to a crystallization treatment. The means for crystallizing this glass molded body is not particularly limited, and for example, a method of holding it in an atmosphere at 500 to 800°C for 5 minutes to 100 hours is used. By such crystallization treatment, calcium phosphate crystallized glass having a crystallinity of 20% or more can be obtained.

In the present invention, the atomic ratio of calcium and phosphorus is Ca/
The surface of a dental material made of calcium phosphate crystallized glass having P of 0.35 to 0.7 is treated with a solution containing a fluorine compound, and then treated with a solution containing a rare earth metal compound. The above-mentioned calcium phosphate crystallized metal compound layer is formed by the darning process, and has water resistance, acid resistance,
Durability such as base resistance is improved. Among these rare earth metal compounds, the method of treatment with a solution containing lanthanum compounds has particularly excellent acid resistance and alkali resistance, and also forms a lanthanum fluoride layer on the surface of dental materials with a color similar to that of natural teeth. preferable.

In the present invention, practical fluorine compounds used in the first stage treatment include sodium fluoride, stannous fluoride, silver diamine fluoride, ammonium fluoride, potassium fluoride, etc. For melting, water, acidic water,
Basic water, alcohol, organic solvents, etc. are suitable. Among these, aqueous solutions and phosphoric acid aqueous solutions are most suitable.

The concentration of the solution containing the fluorine compound is determined as appropriate depending on the type of fluorine compound and solvent used, but it is 0.
A typical range is about 1 to 30%. If this concentration is less than the above range, the fluorine treatment will be insufficient and the following rare earth metal compounds such as rankan compounds will be present.
If the treatment with the solution becomes insufficient and undesirable, and if the concentration exceeds the above range, no improvement in effectiveness will be observed, and there is a risk that the calcium phosphate base material will be damaged or the fluorine treatment layer will become rough. So I don't like it. The treatment with a solution containing such a fluorine compound is 20 to 100'
In C, it is appropriate to carry out the reaction for about 1 minute to about 50 hours. Further, as a treatment method, an appropriate method such as a dipping method or a coating method can be adopted.

Dental materials made of calcium phosphate crystallized glass treated with a solution containing a fluorine compound in this way are
As a second stage treatment, a solution containing a metal compound of the upper right class is used. For example, La, Y, Ce, P
r, Nd, Pm, Sm, Eu.

Cd, Tb, [ly, Ha, Er, 'I'm
, Yb, Lu, and other rare earth metal compounds. Among the red earth metal compounds particularly preferably used in this step, lanthanum compounds include lanthanum chloride, lanthanum acetate, lanthanum perchlorate, and lanthanum bromide.
Dentane etc. are practical, and as its solvent,
Water, acidic water, basic water, organic solvents such as alcohols, etc. are suitable. Among these, aqueous solutions and acidic aqueous solutions are most suitable. The concentration of the solution containing a rare earth metal compound such as a lanthanum compound is determined as appropriate depending on the rare earth metal compound such as a lanthanum compound used and the type of solvent, but it is 0.1 to 3 (
A typical range is approximately H. If this concentration is less than the above range, the treatment with the rare earth metal ions will be insufficient, and the formation of insoluble rare earth metal fluoride compounds such as fluorinated sulfur on the calcium phosphate surface will be insufficient. This is not preferable, and no improvement in effectiveness is observed when the concentration exceeds the above range.

The treatment with a solution containing a rare earth metal compound such as a lanthanum compound is carried out at 20 to 100°C for 1 minute to 50°C.
It is appropriate to do this for about an hour.

Further, as a treatment method, an appropriate method such as a dipping method or a coating method can be adopted.

In this way, dental materials made of fluorine compounds and rare earth metal compound lucium-based crystallized glass have 10 to 1
A fine layer of rare earth metal compound, such as lanthanum fluoride, weighing about 0.00 g is formed. For example, by such a treatment, a thicker lanthanum fluoride layer can be formed than in the intraoral lanthanum fluoride treatment of natural tooth structure, and the durability of dental materials made of calcium phosphate crystallized glass can be improved.

(Example) Examples of the present invention will be described below.

Example 1 CaCO3 powder corresponding to 47 mo1% as CaO and Al(OH) corresponding to 1 mo1% as Al2O3
The reaction product obtained by adding phosphoric acid containing H3PO4 corresponding to 52 mo1% as P2O5 to the mixture with 3 powder was dried and crushed, and then the powder was heated for 400'
The fired product was heated at 125° C. for 5 hours in a platinum crucible.
A glass solution was prepared by melting under stirring at 0° C. for 2 hours.

This glass solution was then subjected to loss molding and then crystallized at 630°C for 20 hours.

The dental crown made of this crystallized glass was immersed in a potassium fluoride 8z aqueous solution, heated to 80° C., and maintained for 5 hours to perform fluorine treatment. Furthermore, this was immersed in a 2z lanthanum chloride aqueous solution and treated at 70°C for 10 hours to perform lanthanum treatment.

Each crystallized glass obtained in each step was immersed in 5 hl of lX104M HCl04 aqueous solution and kept at 50°C for 10 days, and then the concentration of calcium eluted into the solution was quickly measured by ICP method. ,
The results shown in Table 1 were obtained.

Table 1 Example 2 A dental crown made of crystallized glass obtained in the same manner as in Example 1 was immersed in a potassium fluoride 8z aqueous solution, heated to 80° C., and maintained for 5 hours to perform fluorine treatment. Furthermore, this was immersed in the rare earth metal compound solution shown in Table 2 and treated at 70° C. for 10 hours to perform rare earth metal ion treatment. The various samples obtained in this way were each treated with 5hu of lXl0M)IC1Oa (
After immersing it in solution M and keeping it at 50°C for 10 days, the concentration of calcium eluted into the solution was determined by ICP method. The results are also shown in Table 2.

Table 2 (Effects of the Invention) As described above, according to the present invention, the surface layer of a fluorinated rare earth compound, such as a fluorinated porcelain compound, which has high water resistance and acid resistance, is formed by fluorine treatment and treatment with mud metal ions such as lanthanum. By forming 5, it is possible to obtain a calcium phosphate-based crystallized glass dental material that does not deteriorate in strength even in water or an acidic solution, and further suppresses the progression of dental caries.

Claims (2)

[Claims] (1) The atomic ratio of calcium and phosphorus, Ca/P, is 0.35
Calcium phosphate-based crystallization characterized by treating the surface of a dental material made of calcium phosphate-based crystallized glass of 0,7 with a solution containing a fluorine compound, and then treating with a solution containing a rare earth metal compound. How to process glass dental materials. (2) The atomic ratio of calcium and phosphorus Ca/P is 0.35
Claim 1, characterized in that the surface of a dental material made of calcium phosphate-based crystallized glass having a molecular weight of ~0.7 is treated with a solution containing a fluorine compound, and then treated with a solution containing a lanthanum compound. A method for treating a calcium phosphate-based crystallized glass dental material according to item 1.