JPH07206470A - Glass transmitting no x-ray and slowly releasing fluoride ion and dental material containing the same - Google Patents

Abstract

PURPOSE:To provide glass transmitting no X-rays and slowly releasing fluoride ions and a dental material contg. the glass. CONSTITUTION:This glass is oxyfluoroglass consisting of, by weight, 2-17% Si, 0-10% B, 2-13% Al, 10-63% Ba+Sr, 1-16% F and the balance essentially oxygen. This dental material contains the oxyfluoroglass.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to the dental treatment field.
A filling material for treating a tooth defect due to caries or the like, a preventive material applied to the tooth surface to prevent caries, or a dental filling material for a composite filling material, an orthodontic adhesive, and a dental crown material and the dentistry concerned. The present invention relates to a filler for constituting a dental composite material used as a material, and a dental material containing the filler.

[0002]

2. Description of the Related Art In the field of dentistry, it is well known that fluorine has a caries preventive effect. Among the fluorinated sustained-release dental materials that have been used conventionally, there was a cement material known as glass ionomer cement or glass polyalkenoate cement. However, this material has poor durability,
There was a problem with the material itself, rather than the advantage of its sustained-fluorine release function, such as the color tone changing or breaking in a short period of about one year. Further, as a sustained-release polymer material for fluorine, there is known a polymer material containing an acid fluoride group in the side chain of the polymer chain and gradually releasing the fluorine by hydrolysis with water in the oral cavity. This product cannot be applied to parts with high loads, and when it is mixed with a filler to be applied to such parts to form a composite material, the amount of polymer becomes relatively small and the sustained fluorine release amount decreases. There was a problem. In order to provide materials used in the oral cavity with appropriate mechanical properties that can withstand the environment, it is effective to combine a polymer material and an inorganic material, and such materials have been widely used in recent years. There is. In order to provide such a composite material with a sustained fluorine release property, it is considered effective that the inorganic filler, which occupies the majority of the composite material, shares its function.

On the other hand, a dental material is required to have an X-ray opacity that is distinguishable from the dentin of a natural tooth in order to diagnose whether or not dental caries has occurred after treatment or preventive treatment. . To impart X-ray opacity to dental materials, it is generally known to use the following heavy metal-containing glass as an inorganic filler. For example,
(1) 66SiO ₂ , 17BaO, 6B ₂ O ₃ , 11Al ₂ O ₃ (mol%), 49.87SiO ₂ ,
32.80BaO ・ 9.64B ₂ O ₃・ 7.69Al ₂ O ₃ (wt%) (Bowen and Cleek,
X-ray-Opaque Reinforcing Fillers for Composite Ma
terials, J. Dent. Res., 51 (1), 1969) Composition glass.
(2) Barium aluminosilicate (22.5 wt% barium
%that's all). The optimum composition is 25-35SiO ₂ · 10-20Al ₂ O ₃ · 50-60BaO
(wt%) (Dietz USP No. 3826778). (3) La ₂ O ₃ -containing crystallized glass. Contains up to 15wt% La ₂ O ₃ (Muller, Glass
ceramics as composite fillers, J. Dent. Res., 53
(6), 1342-1345 (1974)), etc. Among these are:
Although there are some that suggest the inclusion of fluorine as reported in (1), these are generally added in the field of glass manufacturing with the intention of lowering the melting temperature, and fluoride from glass is used. It is not intended for sustained release of ions.

It has been known that X-ray opacity and fluoride ion sustained release have been achieved at the same time.
There is a glass proposed in No. 233605. However, since this glass contains about 50% by weight of Si component,
There is no choice but to raise the melting temperature. Although there is no description about the melting temperature in this specification, according to the tests by the present inventors, a temperature exceeding 1500 ° C. is required for sufficient melting of the glass of the composition. It is generally known that when the melting temperature exceeds 1400 ° C., the refractory material in the crucible or the melting furnace is eroded by the glass melt, and this phenomenon means that the refractory component is mixed in the glass. Since the dental material is used in the oral cavity, it is an essential condition that the interior of the dental material does not contain a biohazardous component. In particular, recently, the problem of metal allergy has been highlighted, and it is necessary to be composed of safe ingredients as much as possible. Also 1400
If the melting temperature exceeds ℃, the loss due to the evaporation of the fluorine component during melting cannot be avoided.

[0005]

The object of the present invention is to provide a glass composition suitable as a filler for constructing a dental composite material, that is, safe for use in the oral cavity, X-ray opacity and fluoride. A glass composition having combined ion sustained release properties and having excellent fluoride ion sustained release properties while having little elution of components other than fluorine and having excellent durability in the oral cavity,
It is to propose a dental material containing the filler. Furthermore, the present invention is a glass containing a heavy metal, in order to avoid mixing of refractory components and to avoid evaporation of fluorine components in the glass, it is possible to perform melt production at a temperature as low as possible, further, fluoride ion An object of the present invention is to provide a glass composition which has release properties and in which elution of components other than fluoride ions is small.

[0006]

[Means for Solving the Problems] That is, according to the present invention, Si is 2 to 17% and B is 0 to 1 by weight% of constituent elements with respect to the entire glass.
0%, Al is 2 to 13%, Ba and Sr are 10 to 63% in total, and
It is a glass containing 1 to 16% of F. Such glass is 1400
It melts below ℃, has sufficient X-ray opacity and fluoride ion sustained release for dental use, and almost no other components are mixed. Furthermore, the present invention provides a dental material comprising a polymerizable monomer mixture, a polymerization initiator and the above glass.

The glass composition of the present invention is as described above, and the meaning of this composition range will be described below.
It is important that Si does not exceed 17% by weight. This makes it possible to lower the melting temperature. Also, Si
Is more than 17% by weight, the amount of fluoride ions present in the glass cannot be increased, which is not preferable in that the sustained release amount of fluoride ions becomes insufficient. B
However, since it is possible to control the sustained release amount of fluoride ion by its presence as shown in the examples, a necessary amount should be appropriately used. Further, when B exceeds 10% by weight, it becomes difficult to obtain a homogeneous glass. At least the amount of Al
If it is not contained in an amount of 2% by weight, there is a problem in water resistance of the glass, and if it exceeds 13% by weight, the amount of sustained release of fluoride ions from the glass decreases and the melting temperature rises, which is not preferable.
For Ba and Sr, the sum of both is at least 10% by weight
Must be included. Below this amount, the required X-ray opacity cannot be obtained. On the other hand, if the sum of both exceeds 63% by weight, the elution of both alkaline earth metal elements becomes severe and at the same time the ambient pH is raised, which is not preferable from the viewpoint of glass stability and biocompatibility. The fluoride ion is preferably 1 to 16% by weight, preferably 5 to 11%.
It is preferable that the content is wt% in order to secure the elution amount. If it exceeds this amount, the glass is likely to undergo phase separation, and it is difficult to obtain a uniform glass, which is not preferable.

[0008] The composition range defined here indicates the entire range in which a homogeneous glass body exhibiting desired properties is obtained, but a more preferable range is required depending on the intended use of the dental restoration. . This will be specifically shown in Examples below, but the glass composition of the present invention can control the sustained release amount of fluoride ions by adjusting the composition thereof. Therefore, the composition range can be selected with reference to the results of the examples depending on the case where a long-term sustained release is required even with a slight sustained release amount, or when a large amount of sustained release is required at a stretch even for a short period. is necessary. The cause of such a difference in the sustained release amount of fluoride ions has not been clarified yet, but in general, the coordination state of each element differs depending on the amount ratio of the components that make up the glass, that is, the presence around the element It is known that the number of elements of the element changes, and it is said that the strength with which the element is confined in the glass network changes. Microscopically, such a phenomenon occurs inside the glass of the present invention, and it is considered that the sustained release amount of fluoride ions of the resulting glass changes.

As the raw material for producing the glass, various commonly used carbonates, nitrates, natural minerals and the like can be preferably used, and there is no particular limitation. However, it is essential to remove elements that are harmful to the living body. As a raw material of fluorine, barium fluoride, strontium fluoride, aluminum fluoride or the like is preferably used. The raw materials are weighed to have a desired composition, sufficiently mixed and introduced into a melting furnace, and after a sufficient refining time, cooled to be a solid glass. Regarding the dissolution conditions, even within the scope of the present invention, since it depends on the composition, it is necessary to carry out under suitable conditions for each and it is not possible to specify uniformly, but it is generally between 1200 ° C and 1320 ° C. Melting for about an hour is sufficient.

Next, the dental composite material of the present invention is a composition mainly comprising the above-mentioned glass powder, a polymerizable monomer and a polymerization initiator. The glass powder used as the raw material is a glass produced by the above method in the above composition range and pulverized by a known pulverizing means such as a ball mill to a particle size suitable for the intended dental material. For example, in the case of a composite filling / restoring material for treating dental caries, it is ground to an average particle size of about 2 μm. This glass powder is used after being surface-treated in order to improve the affinity with the polymerizable monomer component. As the surface treatment method, any currently known surface treatment method may be applied, but one of the most preferable methods is surface treatment with a silane coupling agent. This includes commonly used silane coupling agents such as
ω-methacryloxyalkyltrimethoxysilane (carbon number between methacryloxy group and silicon atom: 3 to 12),
ω-methacryloxyalkyltriethoxysilane (carbon number between methacryloxy group and silicon atom: 3 to 12),
Organosilicon compounds such as vinyltrimethoxysilane, vinyltriethoxysilane and vinyltriacetoxysilane are used. By this treatment, the glass surface can be more firmly bonded to the polymerizable monomer component.

The content of the filler of the present invention in the composite material can be appropriately selected according to the intended properties of the dental material. That is, for the purpose of particularly emphasizing strength, a content of 70% by weight or more is preferable, and in the case of a coating material for preventing dental caries, fluidity is required, so a low content is preferable. Further, in this case, there is a possibility that the desired fluoride ion sustained-release material cannot be secured only from the inorganic filler, so it is also effective to use it in combination with the above-mentioned fluoride ion sustained-release polymer material. . Further, the dental material group of the present invention, in addition to the polymerizable monomer and the X-ray opaque fluoride ion sustained-release glass of the present invention, inside thereof,
Ultrafine particles having a particle size of 0.1 μm or less, such as spray pyrolyzed silica, can also be included.

As the polymerizable monomer of the composite material of the present invention,
A material generally used for a dental material can be preferably used, and a material having a composition capable of imparting properties according to the purpose of the material can be selected. For example, (meth) acrylic acid alkyl ester (having 1 to 10 carbon atoms in the alkyl group), polyalkylene glycol di (meth) acrylate (having 2 to 20 carbon atoms), ethylene glycol oligomer di (meth) acrylate (2 to 10 mer) ),
Bisphenol A di (meth) acrylate, 2.2-bis [p- (γ-methacryloxy-β-hydroxypropoxy) phenyl] propane, 2,2-di (4-methacryloxypolyethoxyphenyl) propane (in one molecule (2 to 10 ethoxy groups), trimethylolpropane tri (meth) acrylate, pentaerythritol tetra (meth) acrylate and other monofunctional and polyfunctional (meth) acrylic acid esters, and a hydroxyl group (meth) Urethane (meth) acrylic acid esters, which are reaction products of 2 moles of acrylate and 1 mole of diisocyanate, specifically, a single amount as disclosed in JP-B-55-33687 and JP-A-56-152408. The body or the like is suitable. These monomers may be used alone, but it is preferable to use a mixture of two or more kinds of monomers. The monomer is used in the polymerizable resin composition in a proportion of 10 to 50% by weight.

As the polymerization catalyst, that is, the polymerization initiator, which can be used in the composition of the present invention, for example, a combination of an organic peroxide and an aromatic tertiary amine can be mentioned. These are used by blending an organic peroxide in one paste and an aromatic tertiary amine in the other paste. As the peroxide, diacyl peroxides having an aromatic group and peroxyesters that are regarded as esters of perbenzoic acid are preferable, and examples thereof include benzoyl peroxide, 2,4-dichlorobenzoyl peroxide, and m. -Tolyl peroxide, t
-Butylperoxybenzoate, di-t-butylperoxyisophthalate, 2,5-dimethyl-2,5-di (benzoylperoxy) hexane, 2,5-dimethyl-2,5-di [(o-benzoyl) ) Benzoylperoxy] hexane, 2,5-dimethyl-2,5-di [(o-
Benzoyl) benzoylperoxy] hexyne-3,
3,3 ′, 4,4′-tetra (t-butylperoxycarbonyl) benzophenone and the like are effective, and as the tertiary amine, the aromatic group is directly substituted with a nitrogen-primed tertiary group.
Primary amines are preferred, N, N-dimethyl-p-toluidine, N, N-dimethylaniline, N-methyl-N-β-.
Hydroxyethylaniline, N, N-di (β-hydroxyethyl) -aniline, N, N-di (β-hydroxyethyl) -p-toluidine, N, N-di (β-hydroxypropyl) aniline, N, N -Di (β-hydroxypropyl) -p-toluidine, ethyl N, N-dimethylaminobenzoate, isoamyl N, N-dimethylaminobenzoate and the like are effective.

In some cases, it is possible to further impart a photopolymerization function to this composition. In this case, for example, camphorquinone and amine, camphorquinone and organic peroxide and amine, camphorquinone and N. , N
-It is possible to use a conventionally known photopolymerization initiator utilizing visible light described in dimethyl benzoic acid alkyl ester, camphorquinone and aldehyde and organic peroxide, camphorquinone and mercaptan, camphorquinone and azo compound and the like. . However, the above-mentioned organic peroxide and the amine-based accelerator for photopolymerization are not mixed in the same paste at the same time. These catalysts are used in the range of 0.1 to 5% by weight with respect to the polymerizable monomer. In addition, the dental material of the present invention includes a pigment, a polymerization inhibitor, an ultraviolet absorber,
A discoloration preventing agent, an antibacterial agent, and various conventionally known additives can be added.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples. The measured values shown in the following Examples and Comparative Examples are measured according to the following methods. (Eluted substance test) 0.02 mol of crushed glass was precisely weighed, put in an Erlenmeyer flask with a glass lid together with 50 ml of distilled water, and kept in a constant temperature shaking tank at 40 ° C for 8, 15, 24, 3 and
It was taken out after 5 and 48 hours, and the eluate was subjected to ICP (high frequency plasma emission spectrometry) to analyze five elements of Si, B, Ba, Sr and Al. Regarding the fluoride ion, the fluoride ion concentration in the above-mentioned eluate was measured using a fluorine electrode.

Example 1 11.3% of Si, 7.5% of B, and Ba of the total weight of glass.
The raw materials were mixed so as to be 31.5%, Sr 10.0%, Al 1.6% and F 3.3%, and melted at 1320 ° C. A homogeneous glass body was obtained by quenching the melt.

Examples 2 to 16 In the same manner as in Example 1, glass was prepared by changing the composition as shown in Tables 1 and 2. A homogenous glass body could be obtained with any composition.

[0018]

[Table 1]

[0019]

[Table 2]

Comparative Example 1 Si is 9.6%, B is 7.1%, and Ba is 3 with respect to the weight of the entire glass.
The raw materials were mixed and dissolved such that 0.0%, Sr was 11.4%, Al was 3.1%, and F was 18.1%. Although it seemed to be homogeneous in the melt stage, it was devitrified in the cooling stage and a homogeneous glass could not be obtained.

Comparative Example 2 Si is 3.6%, B is 4.6%, and Ba is 3% with respect to the weight of the entire glass.
The raw materials were mixed and dissolved so that 0.0%, Sr was 11.4%, Al was 15.2%, and F was 16.0%. Although a homogeneous glass was obtained,
The amount of fluoride ions eluted from the glass was a low value of about 10 ppm even after 48 hours had elapsed.

Comparative Example 3 Si accounts for 19.0%, B for 2.0%, and Ba for the total weight of the glass.
The raw materials were mixed and melted so that 30.0%, Sr was 11.4%, Al was 9.5%, and F was 2.0%, but a homogeneous glass body could not be obtained.

Comparative Example 4 Si is 0.0%, B is 9.0%, and Ba is 1 with respect to the weight of the entire glass.
The raw materials were mixed and dissolved such that 5.0%, Sr was 15.0%, Al was 9.5%, and F was 11.3%. The obtained glass was considered to be homogeneous, but when left in the air, it absorbed moisture and had a problem in durability.

Comparative Example 5 Si is 3.6%, B is 4.6% and Ba is relative to the weight of the entire glass.
The raw materials were mixed and dissolved so that 5.0%, Sr was 3.0%, Al was 9.2%, and F was 11.3%. The obtained glass was crushed and hydrophobized, and mixed with a polymerizable monomer in the same manner as in Example 12 to obtain a composite filling material. This was cured and the X-ray opacity was compared with an aluminum metal plate and a natural tooth.
It was very weak, and it was difficult to distinguish it from natural teeth.

[0025]

[Table 3]

Example 17 The results of the elution test for the glass produced in Example 13 are shown in FIG. It can be seen that the elution amount of each component increases as the immersion time increases. However, these values were almost the same as or less than the elution amount of each element from the dental x-ray opaque glass for dental use currently on the market. FIG. 2 shows the measurement results of the sustained release amount of fluoride ions from the glasses produced in Examples 11 to 14. It can be seen that the sustained release amount of fluoride ions from the glass body varies considerably depending on the composition. To know the effect of the amount of each component on the fluoride ion sustained release amount,
As a result of various studies, it was found that the amount of boron and the amount of aluminum affected. FIG. 3 shows the results of plotting the elution amount of fluoride ions after 48 hours of Examples 11 to 14 against the amount of boron. From this, it is understood that it is necessary to increase the amount of boron in order to increase the elution amount of fluoride ions. Example 1
The results of plotting the amounts of fluoride ions eluted from 5 and 16 against the amount of aluminum are shown in FIG. Despite the fact that almost the same amount of fluoride ion is contained, the amount of elution is greatly different, and it is considered that the amount of eluted fluoride ion is increased by reducing the amount of aluminum contained in the glass.

Example 18 The glass produced in Example 1 was treated with 2 parts by weight of γ-methacryloxypropyltrimethoxysilane to 100 parts by weight of the glass pulverized with a ball mill to an average particle size of 3 μm to obtain glass particles. Hydrophobized. As a polymerizable monomer,
To a mixture of 70 parts by weight of 2,2-bis [p- (γ-methacryloxy-βhydroxypropoxy) phenyl] propane and 30 parts by weight of triethylene glycol dimethacrylate, 1 part by weight of camphorquinone as a polymerization catalyst and dimethylaminoethyl methacrylate were used. Using 2 parts by weight of the additive, 25 parts by weight of the polymerizable monomer and 75 parts by weight of the hydrophobized glass powder were kneaded to prepare a filling / restoring material. In order to know the strength of this material, the compressive strength was measured for a cylindrical sample having a diameter of 4 mm and a height of 4 mm, and the bending strength was measured for a prismatic sample having a width of 2 mm, a height of 2 mm and a length of 30 mm. An Instron universal tester was used for the measurement, and the crosshead speed was 2 mm / mi for compression.
In bending, it was 1 mm / min. The span of the bending test was 20 mm. Results of the strength test, the restorative material, compressive strength 3500 kgf / cm ^2, notice that with a bending strength 1480kgf / cm ² about the mean value was considered that there is good enough strength as a dental restorative material. Also, the X-ray opacity of the cured product was compared with that of an aluminum metal plate and the enamel of natural teeth, and it was confirmed by X-ray photography that the X-ray opacity was sufficiently identifiable.

Example 19 The glass prepared in Example 1 was treated with 2 parts by weight of γ-methacryloxypropyltrimethoxysilane to 100 parts by weight of the glass pulverized with a ball mill to an average particle size of 3 μm to obtain glass particles. Hydrophobized. Next, 10 parts by weight of 2,2-bis [p- (γ-methacryloxy-βhydroxypropoxy) phenyl] propane as a polymerizable monomer,
To a mixture of 60 parts by weight of bisphenol A polyethoxydimethacrylate (hereinafter referred to as D-2.6E) and 30 parts by weight of triethylene glycol dimethacrylate, 1 part by weight of camphorquinone and 2 parts by weight of dimethylaminoethyl methacrylate as a polymerization catalyst. 75 parts by weight of this polymerizable monomer, 22 parts by weight of hydrophobized glass powder, and ultrafine silica (Aerosil 38
0) 3 parts by weight was kneaded to prepare a tooth surface coating material composition. This composition was filled in a stainless steel mold for producing a disc-shaped test piece having a diameter of 15 mm and a thickness of 1 mm, and the test piece was produced by irradiating with a halogen lamp for 1 minute to obtain a disc. One piece was immersed in 10 ml of distilled water at 37 ° C., and the concentration of fluoride ion eluted in the distilled water was measured with time. The results are shown in FIG. 5, and it was apparent that fluoride ions were eluted from this composite material composition.

[0029]

The glass having a specific composition according to the present invention can be melt-produced at a relatively low temperature, has X-ray opacity and fluoride ion sustained release, and elution of components other than fluoride ion is small, It is a glass suitable as a filler for forming a dental composite material.

[Brief description of drawings]

FIG. 1 is a graph showing the elution amount of each component of glass.

FIG. 2 is a graph showing the amount of fluoride ions eluted from glass.

FIG. 3 is a graph showing the elution amount of each component of glass.

FIG. 4 is a graph showing the amount of fluoride ions eluted from glass.

FIG. 5 is a graph showing the amount of fluoride ions eluted from glass.

Claims (2)

[Claims] 1. A weight percentage of a constituent element with respect to the whole glass,
Si is 2 to 17%, B is 0 to 10%, Al is 2 to 13%, Ba and Sr are 10 to 63% in total and F is 1 to 16%, and other constituents are basically X-ray opaque fluoride ion sustained-release glass characterized by being oxyfluoroglass which is oxygen. 2. A dental material containing a polymerizable monomer mixture, a polymerization initiator, and the X-ray opaque fluoride ion sustained-release glass according to claim 1.