JP5599225B2 - Dental alginate impression material - Google Patents

Description

The present invention relates to an aqueous composition containing alginic acid or a derivative thereof, and a dental alginate impression material comprising an alginic acid-containing aqueous composition and a curing material which suppresses a decrease in the viscosity of the composition over a long period of time and stably maintains the viscosity. About.

  Alginic acid or its derivatives (hereinafter also referred to as “alginic acids”) have the property of forming a very viscous and uniform solution when dissolved in an aqueous solution. It is used as required products, for example, foods such as jams, sauces, mayonnaise, ophthalmic compositions such as eye drops and contact lens care agents. In addition, alginic acid or a derivative thereof is widely used particularly as a dental impression material because it has a property of gelation upon contact with a polyvalent metal ion such as calcium ion.

  However, such alginic acids are known to decrease in viscosity over time in an aqueous solution. For this reason, in an aqueous solution of alginic acid or an alginic acid-containing aqueous composition in which a filler is added thereto, the viscosity cannot be stably maintained over a long period of time, which is a major factor in deterioration of the handling properties of the composition. For this reason, in the alginic acid-containing aqueous composition, maintaining the viscosity stably over a long period of time has been a big problem from the viewpoint of improving the storage stability of the composition.

  In order to overcome the above-described problems, methods have been developed to suppress a decrease in the viscosity of the composition by adding an additive to an aqueous composition containing alginic acids (Patent Documents 1 to 4). However, in any of the above methods, applicable compositions are limited, and the addition of an additive further reduces the initial viscosity of the composition, so that the desired initial viscosity cannot be obtained. There was a problem.

On the other hand, paste-like dental alginate impression materials containing organic hydroxy compounds represented by saccharides have been developed (Patent Documents 5 to 6). The organic hydroxy compound used here is blended for the purpose of improving tooth releasability and tray retention, and satisfying the following formula 1 is used.
(Molecular weight) ÷ (Number of hydroxy groups) <40
Specific examples of the organic hydroxy compound include sugars such as glucose, fructose, mannose, and ribose, sugar alcohols such as sorbitol, mannitol, and maltitol, and polyhydric alcohols such as glycerin. All of the saccharides belong to reducing sugars. However, when these reducing sugars were blended, the decrease in viscosity over time in the aqueous composition of the alginic acids was hardly suppressed.

JP 2006-193475 A JP 2006-206481 A JP 2006-225323 A JP 2006-248960 A JP 2003-171219 A Japanese Patent No. 4322025

Minoru Sakurai, Yoshio Inoue, "Sugar Hydration and Trehalose Physiology", Biophysics, Japanese Society of Biophysics, 1997, 37, 326-330

Against this background, the present invention provides a dental alginate impression material comprising an aqueous composition containing alginic acid or a derivative thereof having a stable viscosity for a long period of time without lowering the initial viscosity and a curing material. The purpose is to do.

  The inventors of the present invention have made extensive studies to overcome the above technical problems. As a result, the present inventors have found that by adding a non-reducing sugar to an aqueous composition containing alginic acids, a decrease in viscosity over time of the composition is suppressed, and the present invention has been completed.

According to the present invention, (A) alginic acid or a derivative thereof, (B) providing water, and (C) a non-reducing sugar to contain luer Luggin acid-containing aqueous composition to consist of a hardened material dental alginate impression material Is done.

In the above dental alginate impression material ,
(C) The number of monosaccharide molecules in which the non-reducing sugar is bound by a glycosidic bond is 10 or less,
(C) the non-reducing sugar is trehalose,
(C) The content of the non-reducing sugar is (A) 1 to 100 parts by weight with respect to 1 part by weight of alginic acid or a derivative thereof,
Is preferred.

Moreover, according to this invention, the dental alginate impression material which added the filler (D) to the said alginic acid containing aqueous composition and was made into the paste form is provided. Furthermore, a dental alginate impression material comprising the above-described alginic acid-containing aqueous composition and a hardener is provided.

  In the present invention, by containing a non-reducing sugar in an aqueous composition containing alginic acid or a derivative thereof, a decrease in the viscosity of the composition over time can be highly suppressed without decreasing the initial viscosity.

In the alginic acid-containing aqueous composition of the present invention, by adding a non-reducing sugar to alginic acid or a derivative thereof, a decrease in the viscosity of the composition is suppressed over a long period of time, and the viscosity is stably maintained.

  Here, alginic acid is a linear polymer in which two types of blocks, β-D-mannuronic acid and α-L-guluronic acid, are (1-4) -bonded, and its derivative is usually a carboxylic acid moiety. Examples of reactants include alginates, ester derivatives of alginic acid, ether derivatives of alginic acid, and the like. Specifically, examples of the alginate include alkali metal alginate such as sodium alginate and potassium alginate; ammonium alginate such as ammonium alginate and triethanolamine alginate. Examples of the alginic acid ester derivative include alkylene glycol alginate such as propylene glycol alginate, and examples of the alginic acid ester derivative include propylene glycol alginate ether. Among these, alkali metal alginate is preferable because of its high water solubility, sodium alginate and potassium alginate are particularly preferable, and sodium alginate is most preferable because it is less likely to cause a decrease in viscosity over time.

  These alginic acid and alginic acid derivatives may be either natural products or synthetic products. Typical natural products include Macrocystis on the west coast of the United States, Lessonia in Chile in South America, Ascophyllum in Northern Europe, etc. Any type of seaweed and locality may be used. The extraction method includes an alkali extraction method and a hot water extraction method, but is not particularly defined. Further, the mannuronic acid / guluronic acid ratio (M / G ratio) constituting alginic acid is not particularly specified, and a wide range of alginic acids from M-rich to G-rich can be used. It is preferable that it is 1.5 or less.

  Commercial products can also be used. Commercially available products are, for example, supplied from Food Chemifa Co., Ltd., Kimika Co., Ltd., Fuji Chemical Industry Co., Ltd., and the like as long as they are alginic acid, sodium alginate, and potassium alginate.

The content of alginic acids in the alginic acid-containing aqueous composition in the present invention is the type, molecular weight, composition (M / G ratio), the type of components coexisting in the composition, and the desired viscosity to be imparted to the composition. It can be set accordingly. The viscosity of the aqueous composition containing alginic acids largely depends not only on the content of alginic acids but also on the molecular weight of alginic acids, and is generally selected from a wide range having a weight average molecular weight of 10,000 to 1,000,000. In order to make the alginic acid-containing aqueous composition have a certain consistency with excellent handleability, the weight average molecular weight is preferably in the range of 20,000 to 300,000. In addition, alginic acids have a property of gelling by contact with a divalent or higher cation (polyvalent metal ion) such as calcium ion, but a composition utilizing the gelling ability of such alginic acids ( Specifically, in a dental alginate impression material), a 1 wt% aqueous solution of alginic acid having a viscosity (23 ° C.) of 50 to 1000 mPa · s is preferably used.

The water contained in the alginic acid-containing aqueous composition in the present invention is not particularly limited, and tap water, ion exchange water, distilled water and the like can be used. Although the content of water is not particularly limited, in the composition using the gelation ability of alginic acids, the water content is 1 to 2000 parts by weight with respect to 1 part by weight of alginic acids, and 10 to 1000 More preferred are parts by weight. When using the A Luggin acid-containing aqueous composition as a dental alginate impression material in combination with a curing material, the content of water is preferably 10 to 30 parts by weight per 1 part by weight alginic acids. If the content is too small, the gelation reaction between alginic acids and polyvalent metal ions may occur unevenly or the gelation reaction may be slow. On the other hand, if the amount of water is too large, the gelation reaction may not easily occur, or the strength of the gel-like cured product after gelation may be reduced.

By adding non-reducing sugars to the alginic acid-containing aqueous composition in the present invention, a composition in which the viscosity is stably maintained over a long period of time can be obtained. The non-reducing sugar used in the present invention is used without any limitation as long as it is a saccharide that does not exhibit reducing properties. The term “reducible” as used herein means having a property of reducing the heavy metal ions such as silver and copper in an alkaline solution. The reducing saccharide is detected by a Torens reagent, a benecto reagent, or a Fering reagent using a reducing action on heavy metal ions, but the non-reducing sugar used in the present invention is a saccharide that is not detected by these reagents. Specific examples of non-reducing sugars include disaccharides trehalose and sucrose, oligosaccharides raffinose, melezitose, stachyose, and cyclodextrins.

  In the present invention, the reason why the viscosity reduction is suppressed by blending a non-reducing sugar with the alginic acid-containing aqueous composition is not necessarily clear, but is estimated as follows. That is, in an aqueous solution containing alginic acids, hydrogen bonds are formed between or within the molecular chains of the alginic acids, and aggregation of the alginic acids occurs. Therefore, it is considered that the viscosity of the aqueous solution decreases with time. On the other hand, when non-reducing sugars are present in an aqueous composition containing alginic acids, water molecules and non-reducing sugars form molecular aggregates, and these molecular aggregates enter between or within the molecular chains of alginic acids. Therefore, it is presumed that the formation of hydrogen bonds, that is, the aggregation of alginic acids is inhibited, and the viscosity reduction of the composition is suppressed.

  If the non-reducing sugar used in the present invention has an excessively high molecular weight, agglomeration occurs due to the formation of hydrogen bonds between the alginic acid and the non-reducing sugar. It is considered to be. For this reason, the non-reducing sugar used in the present invention preferably has 10 or less monosaccharide molecules bonded by glycosidic bonds, and more preferably a disaccharide. When used as a paste-like dental alginate impression material, liquid separation is a cause of deterioration in addition to a decrease in the viscosity of the composition, but trehalose has a particularly high hydration power among non-reducing sugars (Non-patent Document 1). The trehalose is particularly preferably used as a non-reducing sugar, because it tends to form a molecular aggregate with water molecules, and thus liquid separation hardly occurs. Note that sucrose is not suitable for use as a paste-like dental alginate impression material because it becomes a material when bacteria in the oral cavity produce an acid that causes caries.

In the present invention , the content of the non-reducing sugar in the alginic acid-containing aqueous composition is not particularly limited, but is preferably 0.05 parts by weight or more with respect to 1 part by weight of the alginic acid. If the content of the non-reducing sugar is too small, the viscosity reduction of the composition may not be sufficiently suppressed. The upper limit of the content is up to the solubility of the alginic acid, but since it becomes difficult to handle even if the viscosity becomes too high, it is generally 100 parts by mass or less with respect to 1 part by weight of the alginic acid. In addition, regarding the composition utilizing the gelation ability of alginic acids, the gelation reaction is inhibited if there is too much nonreducing sugar relative to alginic acid, so the content of nonreducing sugar is 1 part by weight of alginic acid. The amount is preferably 50 parts by weight or less, more preferably 1 to 10 parts by weight per 1 part by weight of alginic acids.

Reducing sugars that are reducible to alginate-containing aqueous compositions (for example, all monosaccharides such as glucose, mannose and galactose, disaccharides such as maltose, lactose and cellobiose, oligosaccharides such as panose, maltotriose and dextrin) If it contains, the fall of the viscosity of the composition which arises with time will be accelerated | stimulated. The reason why the decrease in viscosity is promoted by blending reducing sugar with the alginic acid-containing aqueous composition is not necessarily clear, but is estimated as follows. That is, it is considered that reducing sugar also has the viscosity suppressing effect as described above, but the reducing property of reducing sugar promotes hydrolysis reaction of alginic acids, that is, reduction of alginic acid molecules. The influence of the viscosity reduction due to the lower molecular weight of alginic acids is far greater than the above-mentioned viscosity suppressing effect, so that it is presumed that the viscosity reduction of the composition is promoted as a result. Therefore, in the alginic acid-containing aqueous composition of the present invention, it is not excluded to contain such reducing sugars in addition to non-reducing sugars, but the content is 1 part by weight of alginic acids. Is preferably 1 part by weight or less, more preferably 0.05 parts by weight or less.

As long as the alginic acid-containing aqueous composition in the present invention utilizes the effects of the invention, its intended use is not specified, and various crystals, such as, It can be used in various fields such as dental materials, pharmaceutical crystals, quasi drugs, cosmetic crystals, food crystals, miscellaneous goods and the like. Specifically, dental alginate impression material compositions, ophthalmic compositions such as eye drops and eye washes, otolaryngological compositions such as nasal drops and ear drops, oral pharyngeal drugs and stomatitis therapeutic drugs, etc. Composition for skin, external composition for skin such as wound medicine, and the like.

Of these, it is particularly suitable to apply to a dental alginate impression material. The dental alginate impression material is an impression material containing alginic acids and a polyvalent metal salt as components, and is mainly used for shaping a tooth at the time of treatment and restoration of a tooth. The above-mentioned dental alginate impression material has features such as good impression accuracy, reproducibility of fine parts, and easy impression operation, and is widely used as a dental impression material. There are two types of dental alginate impression materials, powder type and paste type, but both types react with alginates and polyvalent metal salts in the presence of water to form a hardened body with elasticity. It is used for the impression. As the paste-like impression material, a base paste in which alginic acids are kneaded with water is prepared in advance, and a hardener paste made of a polyvalent metal salt such as calcium sulfate is mixed in use. In the dental alginate impression material of the present invention, (C) a non-reducing sugar alginic acids containing aqueous composition formulated, the in the paste type, the appropriate alginic acids and water in the kneaded base material paste.

A filler may be added to the alginic acid-containing aqueous composition in the present invention in order to adjust physical properties. As the filler, clay minerals such as talc and celite (diatomaceous earth) can be suitably used, and metal or semimetal oxides such as silica and alumina can also be used. The blending amount of the filler is not particularly limited, but when used as a paste-like dental alginate impression material, it is preferably 0.01 to 20 parts by weight with respect to 1 part by weight of alginic acids. 0.1 to 10 parts by weight is more preferable.

In addition, in the alginic acid-containing aqueous composition in the present invention, various components and additives are appropriately selected according to conventional methods according to the use and form as long as the effects of the invention are not impaired. More than that may be used in combination. As those components or additives, for example, carriers (such as aqueous solvents) commonly used in the preparation of semi-solid agents and liquids, thickeners, surfactants, preservatives, bactericides or antibacterial agents, pH Various additives, such as a regulator, an isotonic agent, a chelating agent, and a buffer, can be mentioned.

Hereinafter, in order to specifically describe the present invention, examples, comparative examples , reference examples, and reference comparative examples will be described. However, the present invention is not limited to these examples .

Reference example 1
1.0 g of alginic acid (manufactured by Kimika Co., Ltd., M / G ratio = 1, 2) was dissolved in 1000 g of distilled water in a stirring frame, and after dissolution of alginic acid, 10 g of trehalose was added as a non-reducing sugar and dissolved. .

  About the composition prepared by said method, the viscosity in a 23 degreeC constant temperature water bath was measured using Canon-Fenske viscometer (made by Shibata Kagaku Co., Ltd.) which is a kind of capillary viscometer, and it was set as the viscosity immediately after manufacture. Thereafter, the transparent glass bottle was filled with 50 mL of the composition, sealed, and stored in a thermostatic bath at 50 ° C. for 7 days. After storage for 7 days, the viscosity was measured again, and the viscosity residual ratio (%) was calculated from the measured viscosity value of the composition before and after the heat treatment according to the following formula 2. The composition and the results of the viscosity residual ratio are shown in Table 1.

Viscosity residual ratio (%) = (viscosity after storage at 50 ° C. for 7 days) ÷ (viscosity immediately after production) × 100
Reference Examples 2-4, Reference Comparative Examples 1-3
According to the method of Reference Example 1, alginic acid-containing aqueous compositions having different compositions shown in Table 1 were prepared. Table 1 shows the results of the composition and viscosity residual ratio of each composition. The used sodium alginate and potassium alginate are all manufactured by Kokikai Kimika, and both have an M / G ratio of 1.2.

Reference Comparative Examples 1 to 3 are cases where no non-reducing sugar was contained at all, and in all cases, a decrease in viscosity over time was observed. In contrast, in Reference Examples 1 to 4, alginic acid or a derivative thereof, water, and non-reducing sugar were blended so as to satisfy the configuration shown in the present invention, and in each case, no non-reducing sugar was contained. In comparison with Reference Comparative Examples 1 to 3, it was confirmed that the decrease in viscosity over time was suppressed.

Reference Examples 5-9
In accordance with the method of Reference Example 1, alginic acid-containing aqueous compositions having different compositions shown in Table 2 were prepared. Table 2 shows the results of the composition and viscosity residual ratio of each composition.

In Reference Examples 5 to 9, alginic acid or a derivative thereof, water, and non-reducing sugar were blended so as to satisfy the constitution shown in the present invention. In each case, Reference Comparative Example 3 containing no non-reducing sugar In comparison with the above, it was confirmed that the decrease in viscosity over time was suppressed.

Reference Comparative Examples 4-9
Instead of the non-reducing sugar of Reference Example 1, reducing sugar was added to prepare alginic acid-containing aqueous compositions having different compositions. Table 3 shows the results of the composition and viscosity residual ratio of each composition.

Reference Comparative Examples 4 to 9 are cases where reducing sugars were blended in place of non-reducing sugars, and in any case, in comparison with Reference Comparative Examples 1 to 3 that did not contain reducing sugars, The decrease was promoted.

Reference Examples 10-13
According to the method of Reference Example 1, alginic acid-containing aqueous compositions having different compositions shown in Table 4 were prepared. Table 4 shows the results of the composition and viscosity residual ratio of each composition.

Reference Examples 10 to 13 are cases where a reducing sugar was blended in addition to the non-reducing sugar, and in any case, the viscosity decreased with time in comparison with Reference Comparative Example 3 not containing the non-reducing sugar. Was confirmed to be suppressed.

Reference Examples 14-19
According to the method of Reference Example 1, alginic acid-containing aqueous compositions having different compositions shown in Table 5 were prepared. Table 5 shows the results of the composition and viscosity residual ratio of each composition.

In Reference Examples 14 to 19, alginic acid or a derivative thereof, water, and a non-reducing sugar were blended so as to satisfy the constitution shown in the present invention. In comparison with Reference Comparative Examples 2 and 3, it was confirmed that a decrease in viscosity over time was suppressed.

Example 1
1.0 g of sodium alginate (manufactured by Kimika Co., Ltd.) is dissolved in 20 g of distilled water, dissolved in sodium alginate, and then dissolved by adding 1.0 g of trehalose as a non-reducing sugar. . Og Celite was added to make a paste, and a base paste of a dental alginate impression material was prepared.

  About the base-material paste prepared by said method, the viscosity in 23 degreeC was measured using the spiral viscometer (made by Malcolm Co., Ltd.), and it was set as the viscosity immediately after manufacture. The prepared base paste and hardener paste were mixed at a weight ratio of 3: 1 to evaluate curability. The evaluation criteria were ○ for those that were cured and × for those that were not completely cured. As the curing material paste, a curing material paste of “Tokuyama AP-1” manufactured by Tokuyama Dental Co., Ltd. was used. Thereafter, the transparent glass bottle was filled with 100 mL of the composition, sealed, and stored in a thermostatic bath at 50 ° C. for 7 days. The viscosity was measured again after storage for 7 days, and the residual viscosity (%) was calculated according to Equation 1 from the measured viscosity value of the composition before and after heat treatment. Table 6 shows the composition and the results of the viscosity residual ratio.

Example 2 and Comparative Examples 1 to 4
In accordance with the method of Example 1 , alginic acid-containing aqueous compositions having different compositions shown in Table 6 were prepared. Table 6 shows the composition, viscosity residual ratio, and curability results for each composition.

Comparative Examples 1 to 4 were cases where no non-reducing sugar was contained, and in any case, a decrease in viscosity over time was observed. In contrast, Examples 1 and 2 are those in which alginic acid or a derivative thereof, water, and a non-reducing sugar are blended so as to satisfy the configuration shown in the present invention. In comparison with Comparative Examples 1 and 2 , it was confirmed that the decrease in viscosity over time was suppressed.

Examples 3-7
In accordance with the method of Example 1 , alginic acid-containing aqueous compositions having different compositions shown in Table 7 were prepared. Table 7 shows the composition, residual viscosity, and curability results for each composition.

In Examples 3 to 7 , alginic acid or a derivative thereof, water, and non-reducing sugar were blended so as to satisfy the constitution shown in the present invention. In each case, Comparative Example 1 containing no non-reducing sugar In comparison with 2 and 2 , it was confirmed that the decrease in viscosity over time was suppressed. However, in Example 7 , the amount of trehalose, which is a non-reducing sugar, was too much, so it was not cured even when mixed with a curing material paste.

Claims (5)

(A) alginic acid or a derivative thereof, (B) water, and (C) a non-reducing sugar to contain luer Luggin acid-containing aqueous composition and is characterized by comprising a cured material dental alginate impression material. The dental alginate impression material according to claim 1, wherein (C) the non-reducing sugar has 10 or less monosaccharide molecules bonded by glycosidic bonds. The dental alginate impression material according to claim 1 or 2, wherein (C) the non-reducing sugar is a disaccharide. The dental alginate impression material according to any one of claims 1 to 3, wherein the content of (C) non-reducing sugar is 1 to 100 parts by weight with respect to 1 part by weight of (A) alginic acid or a derivative thereof. Alginic acids containing aqueous composition further (D) is added a filler is obtained by a paste, dental alginate impression material according to any one of claims 1-4.