JP5253528B2 - Dental alginate impression material - Google Patents

Description

The present invention relates to a dental alginate impression material. More specifically, it is a dental alginate impression material used for taking an impression in the oral cavity in dentistry, using a water-based curing agent paste containing a water-soluble polymer, and the water-soluble polymer is based on the material. It is related with the dental alginate impression material which can make up for the gel strength of the gel obtained by the gelation reaction of an alginate and calcium sulfate by carrying out a gelation reaction by kneading with an agent paste.

Conventionally, a dental alginate impression material using a gelation reaction of an alginate has been widely used for obtaining an impression in the oral cavity in dentistry. Properties required for such a dental alginate impression material include that it has an appropriate gel strength, that the impression surface of the cured product obtained after the impression is smooth, and that the resulting cured product has good dimensional stability, The adhesiveness between the cured product and the impression tray is high, the preparation does not require skill, it is easy, and the alginate powder does not scatter.

Here, when using a powder product as an alginate, the gel strength that was originally planned cannot be obtained unless it is kneaded uniformly, and there is a problem that an accurate impression of the tooth cannot be obtained. There is a problem that skill is required to reconcile. There is also a problem that powdered alginic acid is scattered during kneading.

Patent Document 1 discloses a dental alginate impression material composed of a base paste and a hardener paste. Since the dental alginate impression material of Patent Document 1 uses a paste, there is no problem that the alginate powder flies. Also, kneading is relatively easy and can be automated by a kneading machine. Therefore, not much skill is required when kneading is automated. However, in patent document 1, only the mechanism in which an alginate reacts with calcium sulfate and gelatinizes is employ | adopted, and the filler (filler) is not mix | blended with each paste. Therefore, the fastness and gel strength of the resulting gel are not sufficient. Further, since the thickener is not blended in the hardener paste, the hardener such as gypsum aggregates and easily separates from the liquid component, causing a problem in storage stability as a paste. In addition, a cured product composed of alginate and calcium sulfate has problems such as poor water retention with time and water separation over time, resulting in poor dimensional stability of the resulting cured product. In addition, as mentioned above, since no thickener is blended in the filler or hardener paste, when the paste is kneaded, if the kneading is insufficient, it partially gels and generates a spice There is. In view of these problems, the dental alginate impression material using the paste described in Patent Document 1 has not been put into practical use.

  Further, in the dental alginate impression material disclosed in the prior art, a water-soluble polymer is blended in the curing agent paste, and the water-soluble polymer is synergistically mixed with the base paste to synergize with the gel strength. There is no disclosure or suggestion about the increase.

By the way, it is also considered that the hardener paste is not aqueous but non-aqueous (hydrophobic). Patent Document 2 discloses a dental alginate impression material in which a base paste containing an alginate is water-based, and a hardening agent paste containing calcium sulfate contains glycerol or silicone oil. Patent Document 3 discloses a dental alginate impression material in which a base paste containing an alginate and a water-soluble polysaccharide is water-based, and a hardener paste containing calcium sulfate contains polybutene. Furthermore, Patent Document 4 discloses a dental alginate impression material comprising a base paste containing an alginate and a curing agent paste made of calcium sulfate and an organic solvent.

  However, since the dental alginate impression materials described in Patent Documents 2 to 4 have a hydrophobic (non-aqueous) curing agent paste, uniform mixing with an aqueous base paste is difficult. For this reason, attempts have been made to reduce the amount of the curing agent paste to be less than the amount of the base paste so that it can be kneaded as uniformly as possible, but even in that case, the paste is relatively easy to knead, but is uniform. Skillfulness requires skill. In addition, even if a skilled person kneads, since the saliva in the oral cavity is aqueous in the first place, the dental alginate impression material formulated with a non-aqueous hardener paste is sufficient in contact with the patient's teeth. Is not familiar. Therefore, an oil film is formed between the tooth and the cured product, the impression surface of the obtained cured product becomes inaccurate, and there is a problem that it acts as a separating agent from the impression tray when taking an impression of the oral cavity and peels off from the tray. .

  In addition, in order to prevent such a problem, addition of a surfactant to any paste of a dental alginate impression material has also been studied. There is a problem that it becomes worse. As a result, there is a problem that the surface properties of the gypsum model prepared based on the cured product are also deteriorated.

Japanese Patent Laid-Open No. 26-1142 JP 58-35105 A JP 2002-87922 A Japanese Patent Laid-Open No. 7-112910

Therefore, the present invention can be cured by incorporating a water-soluble polymer in the curing agent paste and adopting a mechanism that synergistically increases the gel strength by kneading the water-soluble polymer with the base paste. Dental alginate impression material with appropriate gel strength, smooth impression surface of the cured product obtained after taking the impression, good dimensional stability of the cured product and good adhesion to the impression tray The purpose is to provide.

The dental alginate impression material of the present invention is a dental alginate impression material comprising an aqueous hardener paste and an aqueous base paste, the hardener paste comprising calcium sulfate and the calcium sulfate. A water-soluble polymer that does not undergo a gelation reaction, a filler, and water as a solvent, and the base paste includes an alginate, a retarder, and water as a solvent. Ri Oh a polymer having a property of reacting gelled by kneading with the base paste, galactomannan, glucomannan, xanthan gum, one or more polymer selected from the group consisting of polyvinyl alcohol and tamarind seed polysaccharide and wherein the der Rukoto.

  The present invention employs a mechanism in which the gel strength is synergistically increased by kneading the water-soluble polymer with the base paste by having such a configuration, the gel strength after curing is appropriate, and the impression It is possible to provide a dental alginate impression material in which the impression surface of the cured product obtained after collection is smooth, and the resulting cured product has good dimensional stability and adhesion to the impression tray.

  By having such a configuration, the gel strength produced by the reaction of alginate with calcium sulfate is achieved by the gel obtained by the gelation reaction of the water-soluble polymer in the hardener paste with the components in the base paste. Since it can be supplemented, it is not necessary to mix an alginate in the base paste.

  The water-soluble polymer is preferably galactomannan and / or glucomannan, and the base paste preferably comprises carrageenan or xanthan gum. Moreover, it is preferable that the compounding ratio of the said galactomannan and / or glucomannan and the said carrageenan or xanthan gum is 9: 1 to 1: 9 (weight ratio).

  Preferably, the water-soluble polymer is xanthan gum, and the base paste comprises one or more water-soluble polysaccharides selected from the group consisting of galactomannan, glucomannan and carrageenan. Moreover, it is preferable that the mixture ratio of the said xanthan gum and the said water-soluble polysaccharide is 9: 1 to 1: 9 (weight ratio).

  It is preferable that the water-soluble polymer is tamarind seed polysaccharide and the base paste contains sugar. Moreover, it is preferable that the compounding ratio of the said tamarind seed polysaccharide and the said sugar is 9: 1 to 1: 9 (weight ratio).

  It is preferable that the water-soluble polymer is polyvinyl alcohol (hereinafter referred to as PVA) having a saponification degree of 85 to 95, and the base paste contains borax and / or borate. Moreover, it is preferable that the compounding ratio of the said PVA and the said borax and / or borate is 1000: 1-10: 1 (weight ratio).

  Especially when the water-soluble polymer is selected from these, the gel strength of the obtained cured product is synergistically increased, the cured product has little water separation, and a product with good dimensional stability can be obtained. Moreover, it is excellent in adhesiveness with the impression tray, and the handleability is improved.

  The galactomannan is preferably one or more galactomannans selected from the group consisting of locust bean gum, tara gum or guar gum.

  By having such a configuration, the gel strength of the gel obtained by the gelation reaction between the alginate and the calcium sulfate can be sufficiently compensated by the gelation by the combined use with carrageenan or xanthan gum.

According to the present invention, by setting a water-soluble polymer in the curing agent paste and adopting a mechanism that synergistically increases the gel strength by kneading the water-soluble polymer with the base paste, Dental alginate impression material with appropriate gel strength, smooth impression surface of the cured product obtained after taking the impression, good dimensional stability of the cured product and good adhesion to the impression tray Can be provided.

  The dental alginate impression material of the present invention is a dental alginate impression material comprising an aqueous hardener paste and an aqueous base paste.

The curing agent paste will be described. The curing agent paste contains calcium sulfate, a water-soluble polymer that does not gel with calcium sulfate, a filler, and water as a solvent .

  Calcium sulfate is a necessary component when the alginate in the base paste described later gels. As calcium sulfate, one or more of anhydrous gypsum, hemihydrate gypsum, and dihydrate gypsum are preferable. The content of calcium sulfate may be an amount necessary for the alginate in the base paste to gel, and is usually 3 to 40% by weight based on the obtained paste cured product. It exists in the point which can obtain optimal gel intensity | strength as a dental alginate impression material by supplementing the gel intensity | strength by the water-soluble polymer mentioned later by being in the range of the said content.

  The “water-soluble polymer that does not gel with calcium sulfate” is a component that gels by kneading with a base paste. The reason why the water-soluble polymer is limited to those that do not gel with calcium sulfate is that one of the objects of the present invention is to compensate for the gel strength of the gel produced by the gelation reaction between alginate and calcium sulfate. Because it is. That is, when the curing agent paste is kneaded with the base paste, the gelation reaction of the water-soluble polymer is preferably started at the same time as the gelation reaction between the alginate and calcium sulfate. When the molecule reacts with calcium sulfate, the gelation reaction proceeds with the curing agent paste alone without mixing the base paste and the curing agent paste, and kneaded with the base paste. However, the gel strength of the gel obtained by the gelation reaction of alginate cannot be sufficiently compensated. Therefore, the water-soluble polymer blended in the curing agent paste includes xanthan gum, rhamzan gum, carrageenan (copolymers such as κ, λ, ι or their hybrid type), galactomannan (locust bean gum, tara gum, guar gum) , Fenugreek gum), tamarind seed polysaccharide (including galactose side chain removed), cassia gum, glucomannan, psyllium seed gum, soybean polysaccharide, pectin (low methoxyl type, high methoxyl type, low methoxyamide type, sugar Bead-derived pectin), gum arabic, gati gum, tragacanth gum, karaya gum, native gellan gum, deacylated gellan gum, pullulan, curdlan, macrohomopsis gum, gelatin, agar, methylcellulose (MC), hydride Cellulose derivatives such as xyloxymethylcellulose (HPMC), sodium carboxymethylcellulose (CMC), hydroxypropylcellulose (HPC), hydroxyethylcellulose (HEC), water-soluble hemicellulose, processed and modified starch, raw starch (raw starch), dextrin, Among sodium hyaluronate, PVA, polyvinyl pyrrolidone, carboxyvinyl polymer, etc., those that react with calcium sulfate to cause a gelation reaction are not included. In addition, even if it is a water-soluble polymer that has the property of thickening when added in a small amount and gelling by increasing the amount added, it does not gel in the concentration range used as a dental alginate impression material It can be used without.

  Regarding the content of these water-soluble polymers, it is difficult to set the range of the content uniformly because there is a difference in the gel strength expressed depending on the type of the water-soluble polymer used. The gel strength of the alginate impression material is defined as JIS T6505 (dental alginate impression material) with a permanent strain of 5% or less, an elastic strain of 5% or more and 20% or less, and a compressive strength of 0.35 MPa or more. Therefore, it is necessary to adjust the addition amount so as to meet such specifications.

  As the filler, all known ones used for dental alginate impression materials can be used. Examples of known fillers include diatomaceous earth, silica, talc, calcium carbonate, aluminum hydroxide, perlite, mica, and the like. As content of a filler, it is 2 to 50 weight% in a hardening | curing agent paste.

As other components, it is also possible to add a metal fluoride or silicofluoride as a surface modifier for a plaster model. Specific examples include sodium hexafluorotitanate, potassium hexafluorotitanate, and potassium hexafluorozirconate. In addition, additives such as metal oxides such as magnesium oxide, zinc oxide, aluminum hydroxide, and aluminum silicate, metal hydroxides, colorants, and fragrances may be blended as necessary.

Water is a component that serves as a solvent for the curing agent paste. The type of water is not particularly limited, and for example, purified water, ion exchange water, physiological saline, deep ocean water, and the like can be used. Since the water content increases and decreases depending on the content of the water-soluble polymer, it is difficult to set it uniformly. Therefore, as a standard for making a paste, it can be 20 to 80% by weight.

Thus, since the solvent which comprises a hardening | curing agent paste is water, it can be easily kneaded with an aqueous base paste. Moreover, the paste after kneading has good stability, and an oil film is not formed between the teeth when taking an impression. Therefore, an impression having a smooth surface can be obtained, and as a result, the surface property of the plaster model produced based on the obtained cured product is excellent.

The base paste will be described. The base paste contains an alginate, a retarder, a filler, and water as a solvent .

Alginate is a gelling agent that forms a gel by causing a gelation reaction with the aforementioned calcium sulfate. A dental alginate impression material using an alginate is more convenient in terms of economy, strength as an impression material, and the like, compared to an impression material using agar that has been widely used conventionally. As the alginate, one or more of sodium, potassium, ammonium and triethanolamine salts of alginic acid are preferable. The alginate content may be an amount necessary for gelation by the gelation reaction with calcium sulfate in the hardener paste, and usually 2 to 25% by weight is incorporated in the base paste. . By being in the range of the content, it is preferable in that the gel strength optimal as a dental alginate impression material can be obtained by supplementing the gel strength with the aforementioned water-soluble polymer.

  A retarder is contained to retard the gelation reaction between alginate and calcium sulfate. That is, it is contained in order to prevent the gelation reaction from occurring before the desired time when the dentist who is the surgeon kneads the hardener paste and the base paste. As the retarder, any known retarders used for dental alginate impression materials can be used. Examples of known retarders include alkali metal phosphates, oxalates, carbonates, and the like. The content of the retarder is 0.1 to 5.0% by weight in the base paste. Since some retarders react with gypsum (calcium sulfate) and the function as a retarder decreases, they are blended into the base paste.

As the filler, all known ones used for the aforementioned dental alginate impression material can be used. The filler content is 2 to 60% by weight in the base paste.

  Water is a component that serves as a solvent for the base paste. It does not restrict | limit especially as a kind of water, The above-mentioned thing can be used. The water content can be appropriately set within a range where it is not difficult to knead the base paste and the curing agent paste. As a guide, it can be 10 to 80% by weight.

  Next, it will be described that the gelation reaction is caused by kneading the water-soluble polymer in the curing agent paste and the base paste.

The water-soluble polymer in the aforementioned curing agent paste is characterized by causing a gelation reaction by kneading with the base paste. That is, by causing the gelation reaction in this way, the gel strength of the gel obtained by the gelation reaction between alginate and calcium sulfate can be compensated. The gelation reaction with a water-soluble polymer is characterized in that the gel strength is remarkably increased as compared with the case where a water-soluble polymer is used alone. Specific examples of water-soluble polymers that can be used include, for example,
(1) When galactomannan and / or glucomannan is contained as a water-soluble polymer and carrageenan or xanthan gum is contained in the base paste,
(2) When xanthan gum is contained as a water-soluble polymer, and the base paste contains one or more water-soluble polysaccharides selected from the group consisting of galactomannan, glucomannan and carrageenan,
(3) When tamarind seed polysaccharide is contained as a water-soluble polymer and sugar is contained in the base paste,
(4) When PVA having a saponification degree of 85 to 95 is contained as a water-soluble polymer, and borax and / or borate is contained in the base paste,
Is mentioned. These water-soluble polymers are each independent, and when dissolved in a small amount in water, they do not gel but only thicken or do not show sufficient gel strength even if gelled It is. However, by using the combinations as exemplified, it is possible to obtain a gel exhibiting a large gel strength that was not obtained when used alone without adding an extremely large amount. As a result, the gel strength of the gel obtained by the gelation reaction between alginate and calcium sulfate can be sufficiently compensated, it is not necessary to use an excessive amount of alginate, and an excessive amount of water-soluble There is no need to use the polymer alone. Moreover, since the gel obtained has excellent water retention and does not easily cause water separation, the cured product after the impression is taken does not shrink due to water separation, and the dimensional stability is improved.

  Each water-soluble polymer described above will be described. Galactomannan is a water-soluble polysaccharide having a structure composed of a main chain in which β-D-mannose is β-1,4 bonded and a side chain in which α-D-galactose is α-1,6 bonded. Examples of galactomannans include locust bean gum, tara gum, guar gum, fenugreek gum, etc. The ratio of mannose to glucose is about 4: 1 for locust bean gum, about 3: 1 for tara gum, and about 2: 1 for guar gum. The fenugreek gum is about 1: 1. Since galactomannan does not react with calcium sulfate, it can be blended in the curing agent paste. Among these, from the viewpoint that the gel strength tends to increase synergistically by kneading with the base paste, it is preferable to use locust bean gum, tara gum, guar gum, and further to use purified locust bean gum. preferable.

  Glucomannan is a water-soluble polysaccharide having a structure in which D-glucose and D-mannose are linked by β-1,4, and the ratio of glucose to mannose is about 2: 3. Since there is a unique irritating odor when the degree of purification is low, it is preferable to use one with a high degree of purification. Since glucomannan does not react with calcium sulfate, it can be blended in the curing agent paste.

  Carrageenan is a water-soluble polysaccharide extracted from red algae and has a structure in which galactose is linked by β-1,3. Carrageenan has been found to have eight components of κ, λ, ι, μ, ν, θ, ζ, and π, but three types of κ, λ, and ι are widely used commercially. . Of these, κ and ι carrageenans are gelled. κ-carrageenan has one half-esterified sulfate group for two galactose groups and λ-carrageenan has two half-esterified sulfate groups for two galactose groups, whereas ι carrageenan has two sulfates for two galactose groups Have a group. Kappa carrageenan forms a brittle and hard gel, whereas iota carrageenan forms an elastic gel and increases the gel strength in the presence of cations such as potassium and calcium. Therefore, in this invention, it mix | blends in a base paste.

  Xanthan gum is a polysaccharide produced outside the cell by Xanthomonas campestris. It is derived from D-mannose, D-glucuronic acid, and D-mannose acetylated to anhydroglucose in which β-D-glucose is bound to 1,4. Is a water-soluble polymer having a structure in which side chains are bonded. Since xanthan gum does not react with calcium sulfate, it can be blended in the curing agent paste. In addition, the gelling effect is not recognized with xanthan gum alone.

  When the galactomannan and / or glucomannan is used as a water-soluble polymer in the curing agent paste and the carrageenan or xanthan gum is blended in the base paste, the galactomannan and / or glucomannan and the carrageenan or xanthan gum The blending ratio is preferably 9: 1 to 1: 9 (weight ratio), more preferably 6: 4 to 1: 9, and particularly preferably 5: 5 to 3: 7. By blending at such a blending ratio, the gel strength of the resulting gel increases synergistically, and the gel strength of the gel of alginate and calcium sulfate can be sufficiently compensated.

  Further, when the xanthan gum is a water-soluble polymer in the curing agent paste and the galactomannan and / or glucomannan is blended in the base paste, the blending ratio of the xanthan gum and the galactomannan and / or glucomannan Is preferably 9: 1 to 1: 9 (weight ratio), more preferably 9: 1 to 4: 6, and particularly preferably 8: 2 to 5: 5. By blending at such a blending ratio, the gel strength of the resulting gel increases synergistically, and the gel strength of the gel of alginate and calcium sulfate can be sufficiently compensated.

  Tamarind seed polysaccharide is a water-soluble polymer obtained by extraction from the endosperm portion of leguminous tamarind seeds. Tamarind seed polysaccharide reacts with sugar or alcohol to cause a gelling reaction. Therefore, when using tamarind seed polysaccharide as the water-soluble polymer, a base paste is preferable. The sugar is not particularly limited, but sugar alcohols, particularly xylitol, erythritol, maltitol, and the like are preferable in consideration of the use of the dental alginate impression material. The alcohol is not particularly limited as long as it is water-soluble, but ethanol is preferable in consideration of the use of the dental alginate impression material.

  When the tamarind seed polysaccharide is a water-soluble polymer in a hardener paste and the sugar or alcohol is blended in the base paste, the blending ratio with the sugar or alcohol is 9: 1 to 1: 9 ( Weight ratio) is preferred, 5: 5 to 1: 9 is more preferred, and 4: 6 to 2: 8 is particularly preferred. By blending at such a blending ratio, the gel strength of the resulting gel increases synergistically, and the gel strength of the gel of alginate and calcium sulfate can be sufficiently compensated.

  PVA is a water-soluble polymer obtained by saponifying polyvinyl acetate obtained by polymerizing vinyl acetate with an alkali or an acid. PVA is classified by saponification degree and polymerization degree. Moreover, in this invention, PVA contains modified PVA which has a sulfonic acid, carboxylic acid, etc. in part.

The modified PVA is obtained by copolymerizing a monomer having an ethylenically unsaturated double bond and a monomer having a vinyl ester unit and then saponifying to obtain a carbonyl group-containing PVA, and then washing and drying. This is obtained by randomly introducing unsaturated double bonds starting from a carboxyl group into the main chain.

PVA used in the present invention has a saponification degree of preferably 80% or more, particularly preferably 85% or more, from the viewpoint of excellent solubility in water. Moreover, as a polymerization degree, 100-5000 are preferable, 200-4000 are more preferable, 500-2000 are especially preferable. When it exists in this range, the solubility with respect to water is excellent. PVA gels by a crosslinking reaction with borax and / or borates. Therefore, when PVA is used as the water-soluble polymer, it is preferable to blend borax and / or borate with the base paste.

  As a compounding ratio of the PVA and the borax and / or borate, 1000: 1 to 10: 1 (weight ratio) is preferable, and 500: 1 to 20: 1 is particularly preferable. By blending at such a blending ratio, the gel strength of the resulting gel increases synergistically, and the gel strength of the gel of alginate and calcium sulfate can be sufficiently compensated.

  As described above, according to the dental alginate impression material of the present invention, the gel strength is synergistically increased by blending the water-soluble polymer in the curing agent paste and kneading the water-soluble polymer with the base paste. By adopting a mechanism, the gel strength after curing is appropriate, the impression surface of the cured product obtained after taking an impression is smooth, the dimensional stability of the resulting cured product and adhesion to the impression tray A dental alginate impression material having good properties can be provided.

Next, the aqueous hardener paste for the dental alginate impression material of the present invention will be described. The aqueous hardener paste for dental alginate impression material of the present invention comprises calcium sulfate, a water-soluble polymer that does not gel with calcium sulfate, a filler, and water as a solvent. To do.

Calcium sulfate used in the aqueous hardener paste for dental alginate impression material according to the present invention, water-soluble polymer that does not gel with calcium sulfate, filler, and water as solvent are the same as those described above. Since a thing can be used, description is abbreviate | omitted. Incidentally, the water-soluble polymers, other water, such as gel strength increases synergistically react with a water-soluble polymer base used for the water-based curing agent paste for dental alginate impression material of the present invention in that it is not necessary to blend the advance base paste sex polymer, that use tamarind seed polysaccharide ethers. This is even without first blending other water-soluble polymer in the base paste, since the improvement of the synergistic gel strength by allowed to blend the sugar or alcohol is obtained in the base paste It is.

The aqueous hardener paste for dental alginate impression material of the present invention is not non-aqueous, as disclosed in the prior art. Therefore, kneading can be easily performed when kneading with a water-soluble base paste. In addition, since it contains a water-soluble polymer, it can compensate for the gel strength of the gel obtained by the gelation reaction between alginate and calcium sulfate when kneaded with a base paste containing alginate. Can do. Furthermore, an oil film is not formed between the teeth even when an impression is taken. Therefore, when the aqueous hardener paste for dental alginate impression material of the present invention is used, the cured product obtained after taking the impression is smooth and has good adhesion to the impression tray. The surface property of the plaster model obtained based on such a cured product is also excellent.

Next, the dental alginate impression material of the present invention will be specifically described with reference to examples.

Preparation of base paste A paste containing 6 parts by weight of alginate (viscosity: 500 to 600 cps, molecular weight: 300,000 to 500,000), 1 part by weight of sodium pyrophosphate, 5 parts by weight of diatomaceous earth, 6 parts by weight of calcium carbonate, and the remaining purified water A base paste was prepared by blending water-soluble polymers having a blending ratio shown in Table 1.

Preparation of curing agent paste A paste containing 30 parts by weight of gypsum (dihydrate), 6 parts by weight of diatomaceous earth, 10 parts by weight of calcium carbonate, and the remaining purified water is blended with a water-soluble polymer in the mixing ratio shown in Table 1 and cured. An agent paste was prepared.
In Comparative Example 1, fillers (diatomaceous earth, calcium carbonate) of the base paste and the hardener paste were not blended, and the hardener paste of Comparative Example 2 used liquid paraffin instead of the remaining purified water.

The evaluation method is shown below.
(Gel strength)
The kneading of the curing agent paste and the base paste prepared in each Example and Comparative Example was kneaded using a kneading apparatus “Super Raku Neru” (manufactured by GC Corporation). The kneading ratio of the base paste and the curing agent paste was 4: 1 by volume. With respect to the obtained paste, permanent strain, elastic strain and compressive strength were measured according to JIS T6505 (dental alginate impression material). The results are shown in Table 1.

(Adhesiveness)
The curing agent paste and base paste prepared in each Example and Comparative Example were kneaded using a kneading apparatus “Super Rakuneru” (manufactured by GC Corporation). The kneading ratio of the base paste and the curing agent paste was 4: 1 by volume. 50 g of the obtained paste is placed on an impression metal tray (product name: Impression Tray, Inc., product name: Impression Tray), pressed against a resin jaw model (Nissin Co., Ltd.) at room temperature, and left for 5 minutes. From the following viewpoints, the adhesiveness of the impression material when removing from the jaw model was evaluated. The results are shown in Table 1.

Evaluation criteria for adhesion ○: Impression material held and adhered to tray Δ: Impression material peeled off together with tray, but peeled easily when peeled ×: Impression material peeled off tray

(Surface properties)
The curing agent paste and base paste prepared in each Example and Comparative Example were kneaded using a kneading apparatus “Super Rakuneru” (manufactured by GC Corporation). The kneading ratio of the base paste and the curing agent paste was 4: 1 by volume. After the obtained paste was taken according to JIS T6505 (dental alginate impression material) “compatibility with gypsum”, hard plaster (manufactured by GC Corporation, product name: New Pla Stone) on the impression surface The center line average roughness (Ra) was measured using a surface roughness meter (manufactured by Kosaka Laboratory, product number: Surfcorder SE-3300). Table 1 shows the results of the surface roughness of the obtained gypsum model.

(Water separation)
The curing agent paste and base paste prepared in each Example and Comparative Example were kneaded using a kneading apparatus “Super Rakuneru” (manufactured by GC Corporation). The kneading ratio of the base paste and the curing agent paste was 4: 1 by volume. The obtained paste was poured into a cylindrical mold having an inner diameter of 25 mm and a height of 15 mm, and after curing, the sample was placed on a filter paper laid in a petri dish and left in a constant temperature room at 23 ° C. for 180 minutes in the filter paper. The amount of moisture transferred was measured. The water separation rate was calculated as follows. The results are shown in Table 1.
Water separation rate (%) = (filter paper weight after test (g) −filter paper weight before test (g))
/ Sample weight (g) x100

Examples 1-9, Comparative Examples 1-2
According to the composition shown in Table 1, a curing agent paste and a base paste were prepared and used for each evaluation.

As shown in Table 1, in Comparative Example 1 in which no filler was blended, the compressive strength was small and the adhesiveness was not good. Further, it was expected that water separation was large and dimensional stability was poor. The comparative example 2 which mix | blended the liquid paraffin had bad adhesiveness, and the surface property of hardened | cured material was rough and was not smooth.
On the other hand, according to Examples 1-9, it turned out that it has moderate gel intensity | strength, adhesiveness and surface property are favorable, and hardened | cured material with little water separation is obtained.

  The dental alginate impression material of the present invention is a dental alginate impression material used when taking an intraoral impression in dentistry, and uses a water-based curing agent paste containing a water-soluble polymer. A dental alginate impression material that employs a mechanism that synergistically increases gel strength by blending a water-soluble polymer in a hardener paste and kneading the water-soluble polymer with a base paste. The dental alginic acid is suitable for the gel strength after curing, the impression surface of the cured product obtained after taking the impression is smooth, the dimensional stability of the resulting cured product and good adhesion to the impression tray Since a salt impression material can be provided, it can be suitably used, for example, in the dental field.

Claims (10)

A dental alginate impression material comprising an aqueous hardener paste and an aqueous base paste,
The curing agent paste includes calcium sulfate, a water-soluble polymer that does not gel with calcium sulfate, a filler, and water as a solvent.
The base paste includes an alginate, a retarder, a filler, and water as a solvent,
The water-soluble polymer, Ri Oh a polymer having a property of reacting gelled by kneading with the base paste, galactomannan, glucomannan, is selected from the group consisting of xanthan gum, polyvinyl alcohol and tamarind seed polysaccharide 1 or more dental alginate impression material, characterized in Oh Rukoto a polymer that. The water-soluble polymer is galactomannan and / or glucomannan;
The dental alginate impression material according to claim 1, wherein the base paste comprises carrageenan or xanthan gum.   The dental alginate impression material according to claim 2, wherein a blending ratio of the galactomannan and / or glucomannan and the carrageenan or xanthan gum is 9: 1 to 1: 9 (weight ratio). The water-soluble polymer is xanthan gum;
The dental alginate impression material according to claim 1, wherein the base paste comprises one or more water-soluble polysaccharides selected from the group consisting of galactomannan, glucomannan and carrageenan.   The dental alginate impression material according to claim 4, wherein a mixing ratio of the xanthan gum and the water-soluble polysaccharide is 9: 1 to 1: 9 (weight ratio). The water-soluble polymer is tamarind seed polysaccharide;
The dental alginate impression material according to claim 1, wherein the base paste comprises sugar.   The dental alginate impression material according to claim 6, wherein the blending ratio of the tamarind seed polysaccharide and the sugar is 9: 1 to 1: 9 (weight ratio). The water-soluble polymer is polyvinyl alcohol having a saponification degree of 85 to 95;
The dental alginate impression material according to claim 1, wherein the base paste comprises borax and / or borate.   The dental alginate impression material according to claim 8, wherein a blending ratio of the polyvinyl alcohol to the borax and / or borate is 1000: 1 to 10: 1 (weight ratio).   The dental alginate impression material according to any one of claims 1 to 4, wherein the galactomannan is one or more galactomannans selected from the group consisting of locust bean gum, tara gum or guar gum.