KR101492915B1 - Glass-infiltrated sapphire-alumina composites in the theeth color - Google Patents

Abstract

The glass-infiltrated sapphire-alumina composite according to the present invention is a glass-infiltrated sapphire-alumina composite having a tooth color. The glass-infiltrated sapphire-alumina composite according to the present invention is obtained by mixing colored glass powder with two or more polyvalent metal- Dental restorative materials used for inlays, onlays, veneers, crowns, bridges, dentures, and implants because they are capable of realizing chromaticity and brightness close to natural teeth and having excellent light transmittance and excellent aesthetic effect. Can be usefully used.

Description

Glass-infiltrated sapphire-alumina composites in the theeth color.

More particularly, the present invention relates to a glass-infiltrated sapphire-alumina composite of tooth color, and more particularly to a glass-infiltrated sapphire-alumina composite having a structure in which a colored glass powder mixed with a polyvalent metal-based coloring agent in a base glass powder is melt-infiltrated into a sapphire- Lt; / RTI >

As the economy progressed, there was an era in which the income of the people improved and the concentration of appearance increased. As a result of the recent interest in the esthetics of dental prosthesis, many types of aesthetic restorative materials have been introduced in clinical practice. Among them, nonmetallic restorative materials that do not use metals have been developed and clinical application range has been expanded . Nonmetallic prosthetic restorative materials include, for example, reinforced resins, all ceramics, and metal free post and core. In the ceramic system, since the early all-ceramic system introduced in the mid-80s and early 1980s, only the constituent components of the material were partially improved and the conventional ceramic forming method was used as it is. Thus, the conventional porcelain or crown can not overcome the disadvantages of the conventional porcelain or crown, I was not interested. Since then, all-ceramics with new components and fabrication methods have been developed and used until now. From the early 90's, glass-infiltration ceramic systems and superheated pressure-molding ceramics systems have been mainly used. Recently, a variety of dental ceramics such as zirconium oxide ceramics with high bending strength have been introduced, and research on new dental materials has been actively carried out to date.

It is desirable that the ceramic restorative material of the dental restorer should have a color similar to that of a natural tooth in consideration of aesthetics and the like. For this purpose, Light transmittance is required. As a typical aesthetic crown material conventionally used, there is a crystallized glass excellent in spectroscopic properties, among which lithium disilicate glass-ceramics is most commonly used. It is known that they exhibit light transmittance of 30% to 40% at a wavelength of 550 nm and coloration characteristics close to natural teeth (Non-Patent Documents 1 to 4). However, the reproducibility of color reproduction is lowered through various heat treatment processes such as glass melting-glass crystallization-casting pressurization, and there is a disadvantage in that color deviation is caused by vacuum heat treatment used in casting press. It is required to develop a material for a tooth restoration material which is superior.

Conventionally, in order to adjust the color of the translucent aesthetic restorative material, a method of adding a coloring agent to ceramics was used in the production of the material. This principle appears when electrons in the incomplete 3d orbital of the transition metal ion contained in the coloring agent are excited to a higher energy level by receiving light energy (Non-Patent Document 9 and Non-Patent Document 10). That is, wavelengths of visible light except for these absorption wavelengths collectively indicate color. This electron excitation phenomenon differs depending on the energy difference because the difference in the orbital energy between the base state and the excited state differs depending on the state of anions (oxygen ions) around the transition metal as described in the ligand field theory (non-patent document 10) Various colors can be obtained according to the electron excitation phenomenon. In the case of transition metal ions present in the glass melt, color appears by oxidation-reduction reaction by oxidation-reduction pair. If one such oxidation-reduction pair is present in the glass melt, their valence state is affected by the melting temperature and oxygen partial pressure. That is, the equilibrium shifts toward the lower valence as the melting temperature is higher and the oxygen partial pressure in the atmosphere in the reaction furnace is lower. On the other hand, if it contains two or more oxidation-reduction pairs, the equilibrium between the valence states is determined by affecting the balance of the remaining atoms.

The VITAPAN classical shade guide (VITA Zahnfabrik) and the CIE L ^* a ^* b ^* color space, which are used as criteria for determining the color of an artificial tooth similar to a patient's natural teeth in prosthetic treatment, to be. First, the VITAPAN classical shade guide (VITA Zahnfabrik) is divided into four types of coloring systems: red-brownish line A1-A4, reddish-yellowish line B1- B4, C1-C4 of grayish shades, and D2-D4 of reddishi-gray type (Non-Patent Document 5 and Non-Patent Document 6). In addition, the CIE L ^* a ^* b ^* color space defined by the Commission International de l'Eclairage (CIE) in 1976 can be observed differently depending on the situation or environment of the person observing the color, Since it is difficult to maintain objectivity even in the course of transmitting color, it is designed for accurate measurement, transmission and reproduction of colors (Non-Patent Document 7 and Non-Patent Document 8). Here, L * represents brightness, a ^* and b ^* represent chromaticity coordinates, and L ^* represents a bright color as the value increases and a dark color as the value decreases. + A ^* represents red, a ^* means green, + b ^* means yellow, and -b ^* means blue. Therefore, in order to develop a more reproducible and standard artificial tooth material, it is necessary to develop a translucent aesthetic crown material in accordance with the coloring guide and color system.

Thus, the present inventors have found that the present inventors have found that when two or more polyvalent metal-based coloring agents are added to a base glass powder to prepare pearling glass powder, and the resulting colored glass powder is subjected to a glass infiltration heat treatment process on a sapphire- The chromaticity and brightness of the infiltrated sapphire-alumina composite were not only close to natural teeth but also confirmed excellent light transmittance at a wavelength of 550 nm and completed the present invention.

J. W. McLean and T. H. Hughes, Br. Dent. J., 119 (6) 251-67 (1965); R. A. Giordano, Contin. Educ. Dent., 17, 779-94 (1996); D. W. Jones, Dent. Clin. North Am., 29 (4), 621-44 (1985); W. Holand, and H. Kappert, Adv. Appl. Ceram., 108, 373-80 (2009); S. K. Jun, Pract. Perio. Aesthetic. Dent., 11 (4), 457-64 (1999); J. J. Bosch and J. C. Coops, J. Dent. Res., 74 (1), 374-80 (1995); C. Volpato, M. Fredel, A. Philippi and C. Petter, Ceramic Materials and Color in Dentistry, Ceramic Materials, Wilfried Wunderlich (ed.), Pp 155-174, InTech, China, 2010; R. Ghinea, M. M. Perez and R. D. Paravina, J. Dent., 38, 57-64 (2010); H. Rawson, Properties and applications of glass, pp 208-224, Elsevier, London, 1980; A. K. Varshneya, Fundamentals of inorganic glasses, pp 457-472, Academic press, London, 1994.

It is an object of the present invention to provide a glass-infiltrated sapphire-alumina composite.

It is another object of the present invention to provide a method for producing the glass-infiltrated sapphire-alumina composite.

It is another object of the present invention to provide a glass-infiltrated sapphire-alumina composite for dental restorative materials.

In order to achieve the above object,

The present invention provides a glass-infiltrated sapphire-alumina composite having a structure in which a colored glass powder mixed with a polyvalent metal-based coloring agent in a base glass powder is melt-infiltrated into a sapphire-alumina preform.

The present invention also relates to a method of manufacturing a sapphire and alumina mixture comprising the steps of: (1) forming a sapphire and alumina mixture;

Preparing a preform by plasticizing the mixture formed in step 1 (step 2);

Melt mixing and crushing the glass composition to produce a primary base glass powder (step 3);

Melting and crushing the primary glass powder prepared in the step 3 to prepare a secondary base glass powder (step 4);

A step (step 5) of preparing a coloring glass powder by mixing a polyvalent metal-based coloring agent into the secondary glass powder produced in the step 4; And

And a step (6) of heat-treating and pouring the coloring glass powder prepared in the step (5) into the preform produced in the step (2) (step 6).

Furthermore, the present invention provides a glass-infiltrated sapphire-alumina composite for a dental restorative having a structure in which a colored glass powder mixed with a polyvalent metal-based coloring agent in a base glass powder is melt-infiltrated into a sapphire-alumina preform.

The glass-infiltrated sapphire-alumina composite according to the present invention can be fabricated by melt-impregnating a glass-colored glass powder in which a metal-based coloring agent of two or more polyvalent ions is mixed with a base glass powder, into a sapphire-alumina preform, And is excellent in aesthetic effect due to excellent light transmittance. Therefore, it can be effectively used as a dental restorative material used for inlay, onlay, veneer, crown, bridge, denture, and implant.

1 is a diagram showing a CIE L ^* a ^* b ^* color space, which is a color table system.
FIG. 2 is a graph showing the lightness of the glass-infiltrated sapphire-alumina composite prepared in Examples 1 to 5 and Comparative Examples 1 to 15. FIG.
3 is a graph showing the a ^* b ^* color coordinates of the glass-infiltrated sapphire-alumina composite prepared in Examples 1 to 5 and Comparative Examples 1 to 15. FIG.
4 is a graph showing the light transmittances of the glass-infiltrated sapphire-alumina composites prepared in Examples 3 to 5, Comparative Examples 1 to 11, Comparative Examples 14 and 15.

Hereinafter, the present invention will be described in detail.

The present invention provides a glass-infiltrated sapphire-alumina composite having a structure in which a colored glass powder mixed with a polyvalent metal-based coloring agent in a base glass powder is melt-infiltrated into a sapphire-alumina preform.

As the base glass powder according to the present invention, lanthanum aluminosilicate glass powder may be used, and preferably silicon oxide (SiO ₂ ), boron oxide (B ₂ O ₃ ), aluminum oxide (Al ₂ O ₃ ), Calcium oxide (CaO), and lanthanum aluminosilicate glass powder mixed with lanthanum oxide (La ₂ O ₃ ) can be used.

As the polyvalent metal-based coloring agent according to the present invention, a transition metal compound of titanium oxide (TiO ₂ ) or iron oxide (Fe ₂ O ₃ ), a rare earth metal compound of cerium oxide (CeO ₂ ) . Preferably, a mixture of titanium oxide (TiO ₂ ) and iron oxide (Fe ₂ O ₃ ), which are transition metal compounds, can be used.

The coloring glass powder according to the present invention comprises

94% to 96% by weight of a lanthanum aluminosilicate glass powder as a base glass powder;

3% to 7% by weight of titanium oxide (TiO ₂ ) as a coloring agent; And

And 0.25 wt% to 1.00 wt% of iron oxide (Fe ₂ O ₃ ) as a coloring agent.

In the coloring glass powder, crystallization occurs when titanium oxide (TiO ₂ ) as a polyvalent metal-based coloring agent is less than 3% by weight of the total coloring glass powder. When the coloring glass powder is more than 7% by weight, titanium oxide The color intensity of yellowish brown is increased due to the oxidation of iron oxide (FeO) which has been reduced by oxidation, and the brightness due to the increase of color intensity is decreased, so that the difference in color and brightness between the composite and natural teeth is increased. In addition, when iron oxide (Fe ₂ O ₃ ) as a multi-valent ionic metal-based coloring agent is less than 0.25% by weight (less than 0.25% by weight) of the total coloring glass powder, there is a problem. There is a problem that the color strength of yellowish brown color due to the reduction reaction increases and the light absorption rate by iron oxide increases and the light transmittance decreases.

The coloring glass powder according to the present invention may be contained in an amount of 0.2 wt% to 10.0 wt% based on the total weight of the sapphire-alumina composite.

When the coloring glass powder is less than 0.2% by weight, the amount of the coloring agent which is colored is insufficient, and the white color of the sapphire-alumina composite body is intensely stiff, so that the color difference with the natural teeth is greatly increased, And when it exceeds 10.0% by weight, the brightness decreases due to an increase in addition amount of a metallic coloring agent, and there is a problem that the color is darker than natural teeth.

In addition, it is preferable that the sapphire-alumina preform according to the present invention is prepared by mixing sapphire and alumina in an amount of 65 wt% to 80 wt% to 20 wt% to 35 wt%.

When the content of alumina in the sapphire-alumina preform is less than 20% by weight, the biaxial strength of the glass-infiltrated sapphire-alumina composite to be produced is low, so that it is impossible to absorb and disperse the occlusal load to endure as a dental restorative material. , The polycrystalline alumina scatters light so that the transmittance of light is significantly lowered, resulting in a considerable deterioration of the aesthetic effect.

At this time, the particle size of the sapphire and alumina used in the production of the sapphire-alumina preform according to the present invention is preferably 20 μm to 30 μm and 0.1 μm to 1.0 μm.

When the particle size of the sapphire used in the production of the sapphire-alumina preform is less than 20 μm, there is a problem that the light transmittance of the glass-infiltrated sapphire-alumina composite to be produced decreases. When the particle size exceeds 30 μm, there is a problem. In addition, when the particle size of alumina is less than 0.1 μm, there is a problem that the light transmittance and the mechanical strength of the glass-infiltrated sapphire-alumina composite produced by decreasing the glass penetration strength of the sapphire-alumina preform are decreased. When the particle size exceeds 1.0 μm There is a problem that the mechanical strength is reduced because the alumina fine particles do not sufficiently perform the role of sintering to increase the mechanical strength obtained by forming the neck between the sapphire particles.

The present invention also relates to a method of manufacturing a sapphire and alumina mixture comprising the steps of: (1) forming a sapphire and alumina mixture;

Preparing a preform by plasticizing the mixture formed in step 1 (step 2);

Melt mixing and crushing the glass composition to produce a primary base glass powder (step 3);

Melting and crushing the primary base glass powder prepared in the step 3 to prepare a secondary base glass powder (step 4);

A step (step 5) of preparing a coloring glass powder by mixing a polyvalent metal-based coloring agent into the secondary base glass powder produced in the step 4; And

And a step (6) of heat-treating and pouring the coloring glass powder prepared in the step (5) into the preform produced in the step (2) (step 6).

Hereinafter, a method of manufacturing the glass-infiltrated sapphire-alumina composite according to the present invention will be described in more detail.

First, step 1 according to the present invention is a step of molding a mixture of sapphire and alumina. More specifically, sapphire having a particle size of 20 μm to 30 μm and alumina having a particle size of 0.1 μm to 1.0 μm are mixed at a weight ratio of 7 to 3 to perform dry press molding.

In the wet press molding method, 70% by weight of tertiary distilled water, 3% by weight of polyvinyl alcohol (PVA) and 3% by weight of dispersant are mixed with 100% by weight of a mixture of sapphire and alumina mixed powders, The mixture prepared by mixing in a planetary mixer for 30 minutes is thoroughly dried in an oven to obtain granules through sieving and then molded into a molding for testability using a uniaxial press and a mold.

In this case, the mixing ratio of sapphire and alumina in step 1 is preferably 65 wt% to 80 wt% to 20 wt% to 35 wt%. When the content of alumina is less than 20% by weight, the biaxial strength of the glass-infiltrated sapphire-alumina composite produced is low, so that it is impossible to absorb and disperse the occlusal load to be endured with the dental restorative material. The alumina scattering light significantly reduces the light transmittance and thus has a problem that the aesthetic effect is considerably deteriorated.

Next, the step 2 according to the present invention is a step of plasticizing the mixture formed in the step 1 to prepare a preform. More specifically, the mixture formed in step 1 is heated to a temperature below the melting point of each additive to melt a portion of the alumina, and then the molten part of alumina densifies the sapphire-alumina mixture as a plasticizer.

At this time, it is preferable to perform the heat treatment at 1,500 ° C to 1,650 ° C for 1 hour to 2 hours. If the calcination temperature in step 2 is less than 1500 ° C, the densification of the mixture formed in step 1 is not properly performed, and thus the biaxial strength of the sapphire-alumina preform to be produced is significantly reduced. When the calcination temperature is higher than 1650 ° C There is a problem in that the glass permeability is lowered due to the densification of the preform skeleton due to the high firing temperature, and the residual pores of the composite material to be produced are formed thereby reducing the light transmittance and mechanical properties. When the calcination time is less than 1 hour, the reaction time of alumina and sapphire is short and the densification is not properly performed. As a result, the biaxial strength is lowered. If the calcination time is longer than 2 hours, There is a problem in that it is not economical from an energy point of view.

In addition, step 2 according to the present invention may further include polishing the surface of the fired preform after performing plasticization. The surface of the sapphire-alumina preform produced by calcining in step 2 is polished with # 800 abrasive paper, and then the surface is cleaned with compressed air, so that the glass water infiltration of the sapphire-alumina preform can be promoted.

Next, step 3 of the present invention is a step of melt-mixing and crushing the glass composition to prepare a primary base glass powder, and more specifically, a lanthanum aluminosilicate-based compound is put into a platinum crucible, Melting at a temperature of 1,500 ° C for 1 hour, and quenched and crushed on a stainless steel plate to prepare a primary glass powder.

As the glass composition according to the present invention, a lanthanum aluminosilicate glass powder may be used, and silicon oxide (SiO ₂ ), boron oxide (B ₂ O ₃ ), aluminum oxide (Al ₂ O ₃ ) , Calcium oxide (CaO), and lanthanum oxide (La ₂ O ₃ ) can be used.

Next, step 4 according to the present invention is a step of melting and crushing the primary base glass powder produced in step 3 to prepare a secondary base glass powder, more specifically, The glass powder is charged into a platinum crucible in the same manner as in step 3, melted at a temperature of 1400 to 1500 ° C for 1 hour, and quenched and crushed on a stainless steel plate to prepare a secondary glass powder.

At this time, though not particularly limited, it is preferable to crush the secondary base glass powder so that the particle size of the secondary base glass powder is 20 μm to 70 μm.

Next, the step 5 according to the present invention is a step of preparing a coloring glass powder by mixing a polyvalent metal-based coloring agent into the secondary base glass powder prepared in the step 4, more specifically, Adding a metal-based colorant of a polyvalent ion to the base glass powder, and mixing the mixture with a gyro blender for 0.5 to 2 hours to prepare a crude glass powder.

At this time, as the metal-based coloring agent of the polyvalent ions, a coloring agent made of a transition metal compound such as titanium oxide (TiO ₂ ) or iron oxide (Fe ₂ O ₃ ), a rare earth metal compound such as cerium oxide (CeO ₂ ) And a mixture of titanium oxide (TiO ₂ ) and iron oxide (Fe ₂ O ₃ ), which are transition metal compounds, can be preferably used.

Next, the step 6 according to the present invention is a step of heat-treating and penetrating the coloring glass powder prepared in the step 5 to the preform manufactured in the step 2, and more specifically, the step of infiltrating the sapphire-alumina preform surface And the molten glass powder is mixed with distilled water, placed in a slurry state, and heat-treated at a high temperature to melt-penetrate the glass powder.

At this time, the heat treatment of step 6 according to the present invention may be performed at a temperature of 1100 ° C to 1200 ° C, but is not limited thereto.

In addition, step 6 according to the present invention may further include a step of polishing and slow cooling the glass after the glass penetration. There is an effect of alleviating the stress remaining in the composite by polishing the composite which has been glass-infiltrated by the heat treatment and subjecting the composite to heat treatment in a temperature range of 800 to 900 占 폚.

Furthermore, the present invention provides a glass-infiltrated sapphire-alumina composite for a dental restorative having a structure in which a coloring glass powder containing a polyvalent metal-based coloring agent is glass-infiltrated into a sapphire-alumina preform.

At this time, the glass-infiltrated sapphire-alumina composite for a tooth restoration according to the present invention can be used as a dental restorative material for use in an inlay, an onlay, a veneer, a crown, a bridge, a denture, an implant,

As a result of evaluating the suitability of the glass-infiltrated sapphire-alumina composite according to the present invention as a dental restorative material, the brightness of the glass-infiltrated sapphire-alumina composite according to the present invention is about 63 <L ^* <72, , Chromaticities of -2.1 <a ^* <-1.5 and 4.4 <b ^* <12.4, respectively, and the chromaticity of -2.5 <a ^* <-1.0 and 3 <b ^* <12 of the commercially available lithium disilicate crystallized glass for tooth restoration (See Experimental Example 1). In addition, the light transmittance of the glass-infiltrated sapphire-alumina composite was about 30% or more, which satisfied the light transmittance required for the restoration of deep-sea teeth (see Experimental Example 2). Thus, the glass-infiltrated sapphire-alumina composite according to the present invention can be produced by melt-impregnating a colored glass powder having two or more polyvalent metal-based coloring agents mixed with lanthanum aluminosilicate base glass powder into a sapphire-alumina preform, And the light transmittance can be obtained.

Accordingly, the glass-infiltrated sapphire-alumina composite according to the present invention has a brightness close to natural teeth by melt infiltration of a coloring glass powder containing two or more polyvalent metal-based coloring agents on a sapphire-alumina preform, And light transmittance can be realized. Therefore, since the aesthetic effect is excellent, it can be effectively used as a dental restorative material used for inlay, onlay, veneer, crown, bridge, denture, and implant.

Hereinafter, the present invention will be described in detail with reference to Production Examples, Examples and Experimental Examples.

However, the following Production Examples, Examples and Experimental Examples are illustrative of the present invention specifically, and the content of the present invention is not limited by Production Examples, Examples and Experimental Examples.

< Manufacturing example  1> Sapphire-alumina Preform  Produce

Step 1: Molding of the sapphire-alumina mixture

First, high-purity bulk sapphire was pulverized and sieved to prepare a sapphire powder having an average particle diameter of 26.4 μm. Then, a-alumina (A1100 series, purity 98.5%, density 3.90 g / cm ³ , Spectrum che3mical MFG Co., USA) was pulverized in a planetary mill for 24 hours to prepare alumina having a particle size of 0.3 μm Respectively. The prepared sapphire and alumina were mixed in a weight ratio of 7: 3. The mixture thus prepared was dry-pressed to prepare a sapphire-alumina molding.

Step 2: sapphire-alumina Preform  Produce

The moldings prepared in the step 1 were heated to 10 ° C / min and calcined at 1520 ° C for 1 hour. The sintered sapphire - alumina preforms were polished using # 800 abrasive paper so as to have a thickness of 2.0 mm, and then sapphire - alumina preforms for glass penetration were obtained.

< Manufacturing example  2 - Manufacturing example  14> Preparation of coloring glass powder 1-13

Step 1: Preparation of base glass powder

First, 35% silicon dioxide (SiO ₂ ), 26% boron trioxide (B ₂ O ₃ ), 19% aluminum oxide (Al ₂ O ₃ ), 6% calcium oxide (CaO) and 15% a mixture of lanthanum oxide (La ₂ O ₃₎ to prepare a lanthanum aluminosilicate (lanthanum aluminosilicate) based glass composition. In this case, the raw material for the production of glass are first-rate reagent of silicon dioxide (SiO _2), antimony trioxide, boron (B ₂ O _3), aluminum oxide (Al ₂ O _3), calcium oxide (CaO) and lanthanum oxide (La ₂ O ₃ ) was used. The above reagents were weighed to 100 g on a glass basis, mixed with a gyro blender for 1 hour, and then put into a platinum crucible and melted at 1450 ° C for 1 hour, and quenched and crushed on a stainless steel plate to obtain a glass powder. In order to obtain homogeneous glass, these glass powders were placed in a platinum crucible again and subjected to secondary melting under the same melting conditions as in the primary melting for 1 hour. Thereafter, the secondary-melted glass was quenched and pulverized to prepare a base glass powder having a particle size of 80 μm to 120 μm.

Step 2: Preparation of colored glass powder

To the base glass powder prepared in the above step 1, a polyvalent ionic metal-based coloring agent was added by weight of the coloring agent shown in the following Table 1 to the weight of the whole coloring glass powder, and mixed with a gyro blender for 1 hour, .

Titanium oxide (TiO ₂ ) Iron oxide (Fe ₂ O ₃ ) Cerium oxide (CeO ₂₎ Production Example 2 3 0.75 0 Production Example 3 5 0.75 0 Production Example 4 7 0.75 0 Production Example 5 5 0.25 0 Production Example 6 5 0.5 0 Production Example 7 5 1.00 0 Production Example 8 One 0 0 Production Example 9 3 0 0 Production Example 10 5 0 0 Production Example 11 7 0 0 Production Example 12 0 0.1 0 Production Example 13 0 0.25 0 Production Example 14 0 0.5 0 Production Example 15 0 0.75 0 Production Example 16 0 1.0 0 Production Example 17 0 0 3 Production Example 18 One 0.75 0 Production Example 19 9 0.75 0 Production example 20 5 0.1 0

< Example  1> Preparation of glass-infiltrated sapphire-alumina composite 1

The colorless glass powder (1.3 g) prepared in Preparation Example 2 was mixed with distilled water (1.0 ml) to prepare a slurry. The prepared slurry was added to the sapphire-alumina preform for glass penetration test specimen × height = 12 mm × 2 mm, 1.5 g), and then heat-treated at 1150 ° C. for 80 minutes to permeate the glass melt into the porous preform. After infiltration with glass, both surfaces were polished in parallel using a planar grinder and polished to a thickness of 1.0 mm using # 800 abrasive paper. Finally, the polished specimens were heat - treated at 850 ℃ for 10 minutes to prepare glass - infiltrated sapphire - alumina composites.

< Example  2> Preparation of glass-infiltrated sapphire-alumina composite 2

The procedure of Example 1 was repeated, except that the colorless glass powder prepared in Preparation Example 2 was used instead of the crude glass powder prepared in Preparation Example 2, and the glass-infiltrated sapphire-alumina Complex.

< Example  3> Preparation of glass-infiltrated sapphire-alumina composite 3

The procedure of Example 1 was repeated, except that the colorless glass powder prepared in Preparation Example 2 was used instead of the crude glass powder prepared in Preparation Example 2, and the glass-infiltrated sapphire-alumina Complex.

< Example  4> Preparation of glass-infiltrated sapphire-alumina composite 4

The procedure of Example 1 was repeated except that the colorless glass powder prepared in Preparation Example 2 was used instead of the crude glass powder prepared in Preparation Example 2 to prepare glass infiltrated sapphire-alumina Complex.

< Example  5> Preparation of glass-infiltrated sapphire-alumina composite 5

The procedure of Example 1 was repeated except that the crude glass powder prepared in Preparation Example 2 was used instead of the crude glass powder prepared in Preparation Example 2 to prepare glass infiltrated sapphire-alumina Complex.

< Example  6> Preparation of glass-infiltrated sapphire-alumina composite 6

The procedure of Example 1 was repeated except that the colorless glass powder prepared in Preparation Example 2 was used instead of the crude glass powder prepared in Preparation Example 2 to prepare glass-infiltrated sapphire-alumina Complex.

< Comparative Example  1> Preparation of glass-infiltrated sapphire-alumina composite 7

The procedure of Example 1 was repeated except that the base glass powder prepared in Step 1 of Production Example 2 was not added instead of using the colorless glass powder prepared in Preparation Example 2 in Example 1, Permeable sapphire - alumina composites were prepared.

< Comparative Example  2> Preparation of glass-infiltrated sapphire-alumina composite 8

The procedure of Example 1 was repeated, except that the colorless glass powder prepared in Preparation Example 2 was used instead of the crude glass powder prepared in Preparation Example 2 to prepare glass-infiltrated sapphire-alumina Complex.

< Comparative Example  3> Preparation of glass-infiltrated sapphire-alumina composite 9

The procedure of Example 1 was repeated, except that the crude glass powder prepared in Preparation Example 2 was used instead of the crude glass powder prepared in Production Example 2, thereby preparing glass-infiltrated sapphire-alumina Complex.

< Comparative Example  4> Preparation of glass-infiltrated sapphire-alumina composite 10

The procedure of Example 1 was repeated except that the coloring glass powder prepared in Production Example 2 was used instead of the coloring glass powder prepared in Production Example 2,

< Comparative Example  5> Preparation of glass-infiltrated sapphire-alumina composite 11

The procedure of Example 1 was repeated, except that the colorless glass powder prepared in Preparation Example 2 was used instead of the crude glass powder prepared in Preparation Example 2, and the glass-infiltrated sapphire-alumina Complex.

< Comparative Example  6> Preparation of glass-infiltrated sapphire-alumina composite 12

The procedure of Example 1 was repeated, except that the colorless glass powder prepared in Preparation Example 2 was used instead of the crude glass powder prepared in Preparation Example 2 to prepare glass-infiltrated sapphire-alumina Complex.

< Comparative Example  7> Preparation of glass-infiltrated sapphire-alumina composite 13

The procedure of Example 1 was repeated, except that the colorless glass powder prepared in Preparation Example 2 was used instead of the crude glass powder prepared in Preparation Example 2 to prepare glass-infiltrated sapphire-alumina Complex.

< Comparative Example  8> Preparation of glass-infiltrated sapphire-alumina composite 14

The procedure of Example 1 was repeated, except that the colorless glass powder prepared in Preparation Example 2 was used instead of the crude glass powder prepared in Preparation Example 2, and the glass-infiltrated sapphire-alumina Complex.

< Comparative Example  9> Preparation of glass-infiltrated sapphire-alumina composite 15

The procedure of Example 1 was repeated, except that the colorless glass powder prepared in Preparation Example 2 was used instead of the crude glass powder prepared in Preparation Example 2, thereby preparing glass-infiltrated sapphire-alumina Complex.

< Comparative Example  10> Preparation of glass-infiltrated sapphire-alumina composite 16

The procedure of Example 1 was repeated, except that the crude glass powder prepared in Preparation Example 2 was used instead of the crude glass powder prepared in Production Example 2 in Example 1 to prepare glass-infiltrated sapphire-alumina Complex.

< Comparative Example  11> Preparation of glass-infiltrated sapphire-alumina composite 17

The procedure of Example 1 was repeated except that the colorless glass powder prepared in Preparation Example 2 was used instead of the crude glass powder prepared in Preparation Example 17 to prepare glass infiltrated sapphire-alumina Complex.

< Comparative Example  12> Preparation of glass-infiltrated sapphire-alumina composite 18

The procedure of Example 1 was repeated except that the colorless glass powder prepared in Preparation Example 2 was used instead of the crude glass powder prepared in Preparation Example 2 to prepare glass-infiltrated sapphire-alumina Complex.

< Comparative Example  13> Preparation of glass-infiltrated sapphire-alumina composite 19

The procedure of Example 1 was repeated except that the colorless glass powder prepared in Preparation Example 2 was used instead of the crude glass powder prepared in Preparation Example 2 to prepare glass infiltrated sapphire-alumina Complex.

< Comparative Example  14> Preparation of glass-infiltrated sapphire-alumina composite 20

The procedure of Example 1 was repeated, except that the crude glass powder prepared in Preparation Example 2 was used instead of the crude glass powder prepared in Preparation Example 2, thereby preparing glass infiltrated sapphire-alumina Complex.

< Experimental Example  1> Evaluation of color and brightness of glass-infiltrated sapphire-alumina composite

The following experiment was conducted to evaluate the suitability of the glass-infiltrated sapphire-alumina composite according to the present invention as a dental restorative material.

To be used as a tooth restorer, it should have a color and brightness close to natural teeth. The color and brightness of the glass-infiltrated sapphire-alumina composite prepared in Examples 1 to 6 and Comparative Examples 1 to 14 according to the present invention were measured. First, the glass infiltrated sapphire-alumina composite having a thickness of 1.0 mm prepared in the above Examples and Comparative Examples was washed with ethanol and the color was measured with a UV-visible spectroscope (UV-2401PC, Shimadzu, Japan). At this time, the measurement wavelength range was 380 nm - 780 nm and the slit width was 2.0 mm. After setting the reference line using the reference sample, the reflectance was measured on the specimen to obtain an L ^* a ^* b ^* colorimetric system. The measured L ^* a ^* b ^* values were used to measure the reflectance of each specimen three times in order to reduce the error, and the measured values were averaged. The color space is expressed as Cartesian coordinates of the horizontal axis represents a ^*, the ordinate b ^*, as shown in Figure 1, exhibited a brightness (L ^*) is a bar figure, where L ^* is the mean brightness (lightness), a ^* and b ^* Means chromaticity coordinates. L ^* means a bright color as the value increases, and a darker color as the value decreases. + A ^* means red, -a ^* means green, + b ^* means yellow, and -b ^* means blue. Using these three values,? E representing the color difference was obtained using the following equation (1). A value of 0 for two specimens means no color difference, and a value of 0-2 means a very slight difference. Also, the values of 2-4 mean noticeable discrimination of color difference, and values of 4-6 mean easily distinguishable color difference. A value of 6-12 means much difference in color, and a value of 12 or more means very much. The results are shown in Fig. 2 and Fig.

2, it can be seen that the glass-infiltrated sapphire-alumina composite prepared by melt infiltration of a coloring glass powder containing a polyvalent metal-based coloring agent into a sapphire-alumina preform according to the present invention has excellent brightness close to natural teeth .

More specifically, in the case of the sapphire-alumina composite prepared in Examples 1 to 6 of the present invention, the addition amount of titanium oxide (TiO ₂ ) and iron oxide (Fe ₂ O ₃ ), which are coloring agents, And the brightness was 63 <L ^* <72, which is close to that of natural teeth. The lightness was decreased from about 67 to 65 as the addition amount of iron oxide (Fe ₂ O ₃ ) was increased, and the brightness of the composite was decreased. This is because the iron oxide (FeO) reduced by oxidizing titanium oxide (TiO ₂ ) This is because the intensity of the color increases as it is oxidized by titanium oxide (TiO ₂ ).

On the other hand, the composites prepared in Comparative Examples 1 to 11 of the present invention were prepared by adding no coloring agent or adding only titanium oxide (TiO ₂ ), iron oxide (FeO) and cerium oxide (CeO ₂ ) . Among these, the composite of Comparative Example 1 prepared using base glass powder and the composite of Comparative Examples 2 to 5 prepared using only titanium oxide as a coloring agent had a brightness of about 75 or higher, and the brightness of the composite was remarkably bright. Further, in the case of the composite prepared in Comparative Examples 6 to 11 using iron oxide (FeO) as a coloring agent, the brightness increased from about 80 to 69 as the addition amount of iron oxide (Fe ₂ O ₃ ) and cerium oxide (CeO ₂ ) . This is because as the colorant is added, the color of the sapphire-alumina composite begins gradually to become darker.

In addition, the composite prepared in Comparative Examples 12 to 14 of the present invention was obtained by varying the addition amount of titanium oxide (TiO ₂ ) and iron oxide (Fe ₂ O ₃ ) added as a colorant, and titanium oxide (TiO ₂ ) In the case of the composite prepared in Comparative Example 12 and Comparative Example 13 in which the amount of iron oxide (Fe ₂ O ₃ ) added was varied, Is about 75% or more. This is because, as compared with Examples 4 to 6 in which the addition amount of iron oxide is increased, the intensity of color is increased due to the addition of a coloring agent, thereby darkening the brightness.

From this, it can be seen that the addition of no coloring agent and the addition of titanium oxide (TiO ₂ ) alone do not change the lightness of the composite to be produced, and iron oxide (Fe ₂ O ₃ ) and cerium oxide (CeO ₂ ) The brightness of the composite is lowered. Further, iron oxide titanium oxide (TiO ₂₎ and (Fe ₂ O ₃₎ is oxidized between the two metals, depending on the relative concentrations - it is the direction of movement of the reduction side, in order titanium oxide gajigi close to brightness of the natural tooth brightness (TiO ₂ ) And iron oxide (Fe ₂ O ₃ ) are important.

As shown in FIG. 3, the chromaticity of the glass-infiltrated sapphire-alumina composite prepared by melt infiltration of the coloring glass powder containing the polyvalent metal-based coloring agent into the sapphire-alumina preform according to the present invention is close to natural teeth.

More specifically, the sapphire-alumina composites prepared in Examples 1 to 6 of the present invention showed -2.1 <a ^* <-1.5 and 4.4 <b ^* <12.4 close to the chromaticity of natural teeth. This is most similar to the currently commercially available lithium disilicate crystallized glasses for tooth restoration materials with chromaticity of -2.5 <a ^* <-1.0 and 3 <b ^* <12.

On the other hand, in the case of the composite of Comparative Example 1 produced by adding no coloring agent and Comparative Example 2 through Comparative Example 11 prepared by adding titanium oxide (TiO ₂ ), iron oxide (FeO) and cerium oxide (CeO ₂ ) The composite of Comparative Example 1 in which a colorant was not added and the composite of Comparative Example 2 to Comparative Example 5 prepared by adding titanium oxide (TiO ₂ ) as a coloring agent exhibited a white color of the sapphire-alumina composite, The difference in chromaticity was remarkably large. Further, in the composite of Comparative Examples 6 to 10 prepared by adding iron oxide (Fe ₂ O ₃ ) alone as a coloring agent, a ^* decreased and b ^* increased as the amount of addition of iron oxide (Fe ₂ O ₃ ) And a ^* increased again from 0.75 wt%. That is, the color change was yellowish green when it was added with iron oxide (Fe ₂ O ₃ ) and yellowish brown when it was more than 0.75 wt%. In addition, the composite of Comparative Example 11 prepared by adding cerium oxide (CeO ₂ ) alone as a colorant exhibited a higher green strength than iron oxide (Fe ₂ O ₃ ).

Further, in the composite of Comparative Example 12 and Comparative Example 13 in which the addition amount of titanium oxide (TiO ₂ ) added as a coloring agent was changed, the amount of iron oxide (Fe ₂ O ₃ ) was gradually increased so that a ^* was decreased and b ^* was increased 0.5% by weight was again a ^* increases From above, the values of a * and B * was higher than that hayeoteul alone was added to the iron oxide (Fe ₂ O _3). This Comparative Example 2 to Comparative Example 6, iron oxide, as in the case of (Fe ₂ O ₃₎ Fe ^{+ 2} (cyan) according to the addition of Fe ³⁺ (amber) As the color of the Jinhae be charged with the green-yellow 0.5 wt.% Because their overlapping colors became darker and became yellowish brown. That is, it means that the color intensity of yellowish brown is increased. In addition, the composite of Comparative Example 14 in which iron oxide (Fe ₂ O ₃ ) added as a coloring agent was added in a low ratio showed a pale greenish-yellow color. As a result, the addition amount of iron oxide (Fe ₂ O ₃ ) was increased as compared with the results of Comparative Example 12 and Comparative Example 13 with reference to Examples 4 to 6 in which the addition amount of iron oxide (Fe ₂ O ₃ ) less when there is the intensity of the green and yellow increases as the two types of iron oxide (FeO (cyan), Fe ₂ O ₃ (amber)) is present in bands or the green and yellow, the amount added is increased together, the iron oxide (Fe ₂ O ₃₎ It can be seen that the intensity of the yellowish brown increases from the starting point where the added amount exceeds 0.5% by weight.

From this, it can be seen that the direction of the oxidation-reduction reaction between the polyvalent metal-based coloring agent differs depending on the addition ratio of the polyvalent metal-based coloring agent used for the coloring glass powder, and the resulting color change of the composite is large.

< Experimental Example  2> glass penetration of sapphire-alumina composite Light transmittance  evaluation

The following experiment was conducted to evaluate the suitability of the glass-infiltrated sapphire-alumina composite according to the present invention as a dental restorative material.

For use as a dental restorative material, it should have a light transmittance close to natural teeth. The absorption wavelength of the transition metal contained in the colorant used in the production of the glass-infiltrated sapphire-alumina composite prepared in Examples 3 to 6, Comparative Examples 1 to 11, and Comparative Example 14 according to the present invention The light transmittance of glass - infiltrated sapphire - alumina composite specimens was measured. The absorption wavelength was measured in the same manner as in Experimental Example 1 except that the light transmittance was measured. At this time, the measurement wavelength range was from 300 nm to 800 nm, and the slit width was 2.0 mm. From the measured transmission spectrum, an average light transmittance (τ _s ) was calculated using the following equation (2), and the result is shown in FIG.

Where? _{S is the} average transmittance;

D _?: Spectral distribution;

V _?: Visible sensitivity; And

? (?): represents the transmittance at the wavelength?.

As shown in FIG. 4, the glass-infiltrated sapphire-alumina composite prepared by melt infiltration of the coloring glass powder containing the polyelectrolyte-based coloring agent into the sapphire-alumina preform according to the present invention has an excellent light transmittance . &Lt; / RTI &gt;

More specifically, the sapphire-alumina composites prepared in Examples 3 to 6 of the present invention showed a light transmittance of about 27% to 33% near the natural teeth at a wavelength of 550 nm, It is understood that the light transmittance is about 30% or more.

On the other hand, the composite of Comparative Example 1 prepared by adding no coloring agent and the composite of Comparative Examples 6 to 11 prepared by adding only iron oxide (Fe ₂ O ₃ ) or cerium oxide (CeO ₂ ) And the optical transmittance of the composite of Comparative Examples 2 to 5 prepared by adding titanium oxide (TiO ₂ ) alone was high. This is because iron oxide (Fe ₂ O ₃ ) and cerium oxide (CeO ₂ ), which are added as a coloring agent, undergo oxidation reaction of iron ions (Fe ^{2 +} ) and cerium ions (Ce ^{3 +} Fe ^{3 +),} and cerium ions (Ce ^{4 +)} is increased, but, titanium oxide (TiO ₂₎ of titanium ions (Ti ^{4 +)} change in the exclusive addition of color and light transmission, because the energy is considerably higher that required for reduction of the .

In addition, impregnated in the addition to the colorant Iron oxide (Fe ₂ O ₃₎ composite of less Comparative Example 14 The addition amount of the exhibited a light transmission close to the natural tooth is the light transmittance of about 36%, wherein the iron oxide (Fe ₂ O ₃₎ (Fe ₂ O ₃ ) was increased from 0.1% by weight to 1.0% by weight, the light transmittance was remarkably increased from about 36% to 27% as shown in Examples 4 to 6 in which the amount of iron oxide Respectively. This is due to the oxidation of iron ions (Fe ^{2 +} ) by titanium oxide (TiO ₂ ) as the addition amount of iron oxide (Fe ₂ O ₃ ) increases, the iron ion (Fe ^{2 +} ) short- ) Moved to the iron ion (Fe ^{3 +} ) long wavelength transmission region (700 nm - 1050 nm) after the oxidation and the light absorption rate increased. In addition, the light transmittance is the inverse of the concentration of the metal ions to act as a colorant, so the strip-tan due to the oxidation of the iron ions (Fe ^{+ 2)} is due to the increase in concentration of iron ions (Fe ^{+ 3).}

From this, it can be seen that the concentration of the metal ion after melt infiltration varies depending on the addition ratio of the polyvalent metal-based coloring agent used for the coloring glass powder, and the concentration of the metal ion affects the light transmittance of the composite to be produced have.

As a result of combining Experimental Example 1 and Experimental Example 2, it was found that the composite prepared by using the base glass powder to which no coloring agent was added had excellent brightness and light transmittance but a large chromaticity difference with natural teeth. The composite prepared by adding titanium (TiO ₂ ), iron oxide (Fe ₂ O ₃ ) and cerium oxide (CeO ₂ ) alone has a chromaticity difference with natural teeth in the case of titanium oxide (TiO ₂ ) and cerium oxide (CeO ₂ ) , And ferric oxide (Fe ₂ O ₃ ), there is a difference in lightness and light transmittance from the natural teeth according to the amount of addition. From this, it can be seen that it is more preferable to use the above-mentioned multivalent metal-based coloring agent in combination. Furthermore, the complexes prepared by adding titanium oxide (TiO ₂ ) and iron oxide (Fe ₂ O ₃ ) have different kinds of metal ions and their concentration after melt infiltration due to the direction of oxidation- And the ratio of the metal-based coloring agent to be mixed is an important parameter for determining the brightness, chromaticity and light transmittance of the glass-infiltrating sapphire-alumina composite, since the brightness, chromaticity and light transmittance of the composite thus prepared are significantly different from each other . As a result of the experiment according to the present invention, it is preferable that titanium oxide (TiO ₂ ) and iron oxide (Fe ₂ O ₃ ) are mixed and added as a polyvalent metal-based coloring agent, and titanium oxide (TiO ₂ ) (Fe ₂ O ₃ ) was added in an amount of 3 wt% to 7 wt% and 0.25 wt% to 0.75 wt%, respectively, in consideration of the oxidation-reduction reaction after the addition, in order to simultaneously satisfy brightness, chromaticity and light transmittance close to natural teeth. Is preferable.

Accordingly, the glass-infiltrated sapphire-alumina composite according to the present invention has a brightness close to natural teeth by melt infiltration of a coloring glass powder containing two or more polyvalent metal-based coloring agents on a sapphire-alumina preform, And light transmittance can be realized. Therefore, it is excellent in aesthetic effect and can be effectively used as a dental restorative material used for inlay, onlay, veneer, crown, bridge, denture, and implant.

Claims (9)

The colored glass powder containing the polyvalent metal-based coloring agent has a structure that is melt-penetrated into the sapphire-alumina preform,
The coloring glass powder may be prepared by,
3% to 7% by weight of titanium oxide (TiO ₂ ) as a coloring agent;
0.25 wt% to 1.00 wt% iron oxide (Fe ₂ O ₃ ) as a coloring agent; And a balance lanthanum aluminosilicate-based base glass powder,
Wherein the coloring glass powder is contained in an amount of 0.2 wt% to 10.0 wt% based on the total weight of the sapphire-alumina composite.
The method according to claim 1,
Wherein the base glass powder is a mixture of lanthanum oxide (La ₂ O ₃ ) mixed with silicon oxide (SiO ₂ ), boron oxide (B ₂ O ₃ ), aluminum oxide (Al ₂ O ₃ ), calcium oxide (CaO) Glass-infiltrated sapphire-alumina composite for a dental restoration, characterized in that it is an aluminosilicate glass powder.
delete delete delete The method according to claim 1,
Wherein the sapphire-alumina preform has a ratio of sapphire to alumina of 65 wt% to 80 wt% to 20 wt% to 35 wt%.
The method according to claim 1,
Wherein said sapphire-alumina preform is comprised of sapphire having a particle size of 20 μm - 30 μm and alumina having a particle size of 0.1 μm - 1.0 μm.
delete The method according to claim 1,
Wherein the tooth restoration material is at least one selected from the group consisting of an inlay, an onlay, a veneer, a crown, a bridge, a denture, and an implant.

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