JPH11209220A - Alginate impression material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an alginate impression material which is soft and readily kneadable when the material is kneaded and has small flowing property (sagging) by own weight of impression material paste when kneading is stopped by making the impression material include xanthan gum and galactomannan. SOLUTION: This impression material comprises (A) 0.05-0.8 wt.%, preferably 0.1-0.7 wt.%, more preferably 0.2-0.7 wt.% xanthan gum, (B) 0.05-10 wt.% preferably 0.1-8 wt.%, more preferably 0.2-7 wt.% galactomannan used in 0.06-20 wt.%, preferably 0.1-10 wt.% weight ratio of the component A to the component B, (C) 3-25 wt.% alginate, (D) 4-30 wt.% gelling agent, (E) 30-85 wt.% filler and (F) as necessary, 0.2-4 wt.% gelation controlling agent, a strain controlling material, a compatibility-improving agent, a dust preventing agent, a coloring agent, a flavoring agent, etc. Guar gum, or Locust bean gum, etc., is preferably used as the component B.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an alginate impression material (hereinafter sometimes referred to as an "impression material"). More specifically, the present invention relates to an alginate impression material which is soft and easy to knead when kneading an impression material, has a small flowability (drip) due to the weight of the impression material paste when the kneading is stopped, and has little change in physical properties with time.

[0002]

2. Description of the Related Art Alginate impression materials are based on the fact that alginate reacts with a gelling reagent such as calcium sulfate to form a gel-like hardened material. And a filler. Such an alginate impression material is suitably used mainly for molding at the time of restoration and restoration of teeth and other moldings.

[0003] As a product form of the alginate impression material,
There are two types, a powder type and a paste type. In any of the commercial forms, an operation of kneading the impression material is involved in use. This kneading operation is a very important operation in using the impression material because it has a function of sufficiently mixing the components, accelerating the dissolution of the components and causing a uniform gelation reaction. If the kneading of the impression material is insufficient, especially the dissolution of the alginate is insufficient and the reaction becomes uneven. As a result, the performance inherent in the impression material cannot be sufficiently exhibited, and the obtained impression cannot be satisfactory, which also affects subsequent work.

[0004]

However, the kneading of the impression material requires a little skill and some power, and is a difficult task for an unskilled person. Therefore, in order to facilitate kneading, there is a method of lowering the viscosity of the impression material at the time of kneading, but the normal viscosity reduction method also lowers the viscosity of the paste at the time of impression acquisition, and the weight of the paste at the time of acquisition is reduced. There is a problem that it is drooped. For this reason, for example, when an impression of a tooth or the like is obtained, the impression material flows out of the impression tray, and a sufficient thickness cannot be obtained at a necessary portion, and the strength of the obtained impression is insufficient, or the required area is not sufficient. The impression may not be obtained, or in extreme cases, may flow into the patient's pharynx, resulting in a very uncomfortable and dangerous situation.

[0005] Further, in the case of a powder type impression material, in order to prevent flowability (drip) due to its own weight, so-called stiffening is performed in which the proportion of water is reduced from a specified amount at the time of use.
The stiffening has a low water content in the finished impression gel body, which tends to reduce the strain due to the load, that is, the elastic strain.Therefore, a load is generated when the mold is removed from the mold portion, and an excessive force is applied. It is easy to damage the impression gel body. On the other hand, in the case of the paste type impression material, the hardness cannot be adjusted by kneading, so that the impression material having reduced viscosity cannot be used at all in terms of physical properties.

On the other hand, in the alginate impression material, the alginate as a main component causes a decrease in viscosity due to depolymerization even under conditions such as transportation and storage, so that the impression material gradually becomes easy to sag when stored for a long period of time. In addition, the strength of the impression material gel body tends to decrease as the viscosity decreases. Impression materials with insufficient strength
It is easy to break when removing from the object to take the impression,
In particular, when taking impressions of teeth, the most important details of the teeth may be damaged.

[0007]

An object of the present invention is to provide an alginate impression material in which the above-mentioned problems relating to flowability (drip) due to its own weight and changes with time in physical properties are improved. As a result of intensive studies for the above purpose, by adding an appropriate amount of xanthan gum and galactomannan into the alginate impression material, the sag is reduced without changing the kneading feeling, and conventionally, the alginate as a main component is It has been found that deterioration can be prevented, and sagging and strength can be prevented from decreasing with time, and the present invention has been achieved. That is, the gist of the present invention resides in an alginate impression material containing xanthan gum and galactomannan.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.
The xanthan gum used in the present invention is a natural fermented polysaccharide composed of a repeating unit of a main chain composed of two glucoses and a side chain composed of two mannoses and one glucuronic acid. Outstanding stability among natural gums,
It has strong acid, salt, and heat resistance, and exhibits extreme pseudoplasticity. In the alginate impression material of the present invention, the content of xanthan gum is 0.05 to 0.8% by weight, preferably 0.1 to 0.7% by weight, more preferably 0.2 to 0.7% by weight.
% By weight. When the content of xanthan gum is small, the effect of reducing sagging is small, and when it is too large, adverse effects such as difficulty in removing air bubbles that are involved in kneading the impression material are caused. If air bubbles generated during kneading remain on the surface of the obtained impression, there is a problem that an important detail impression is lost or air bubbles remaining inside the impression cause a decrease in the strength of the impression gel body. . Also, since the paste has little fluidity at the part where the force is not applied at the time of impression, the paste surface does not become smooth at the time of kneading, it is difficult to judge whether the paste has been kneaded into a uniform paste, and the timing of impression acquisition is missed There is also the problem of getting lost.

On the other hand, galactomannan is a polysaccharide comprising galactose and mannose, and is a nonionic natural water-soluble polymer mainly contained in the endosperm part of legumes in a few to several tens%. . The composition differs depending on the type of plant, adjustment time, and method. Among them, D is preferably used.
The main chain is a linear polymer of β-1,4 bonds of mannose, and the structure unit is a structure in which one galactose group is bonded to every other mannose residue by α-1,6 bonds. Guar gum and locust bean gum. In the alginate impression material of the present invention, the content of galactomannan is 0.05 to 10% by weight, preferably 0.1 to 8%.
%, More preferably 0.2 to 7% by weight. If the content of galactomannan is less than this, the effect of preventing sagging is small, and the effect of preventing the decrease in strength over time is small.If the addition amount is larger than the above range, the viscosity of the impression material is excessively increased. This is undesirable because the feel during kneading becomes hard and kneading becomes difficult.

Since the xanthan gum and galactomannan used in the present invention have good solubility in water, their affinity with water can be improved by sufficiently dispersing them in the impression material. To improve the initial compatibility with the powder. The usage ratio (B / A) of xanthan gum (A) and galactomannan (B) is usually 0.06 to 20, preferably 0.1 to 10.

The alginate impression material of the present invention contains the same components as a normal alginate impression material except that it contains the above-mentioned xanthan gum and galactomannan, and known components can be appropriately selected. For example, alginates include salts of aqueous solutions of sodium, potassium, ammonium or triethanolamine of alginates, and the content is usually 3 to 25% by weight. Also,
As the gelling agent, a compound which dissolves in water to generate a divalent metal ion is preferably used, and calcium sulfate dihydrate,
Examples thereof include calcium sulfate such as calcium sulfate hemihydrate and calcium sulfate anhydrous, and its content is usually 4 to 30% by weight. Further, examples of the filler include diatomaceous earth, talc, silica, aluminum hydroxide, and other metal oxides, and the content is usually 30 to 85% by weight. In addition, gelling regulators, strain regulators, compatibility modifiers, dust inhibitors,
Various additives can be appropriately blended as a coloring agent, a fragrance, and the like. Among these, as the gelling regulator, phosphates, oxalates, silicates, carbonates and the like of alkali metals such as sodium and potassium are used, and the amount used is usually 0.2 to 4% by weight.

The method for producing the impression material of the present invention is not particularly limited, and can be appropriately selected from known methods. For example, put all the raw materials into the mixer at the same time,
Mixing may be performed, or divisional mixing may be performed according to the purpose. Further, the quantitative composition of the impression material in the present specification indicates a composition in terms of powder excluding the solvent in the case of the paste type.

[0013]

The present invention will be described in more detail with reference to the following Examples, which do not limit the present invention. Examples 1 and 2, Comparative Examples 1 and 2 A predetermined mixing operation was performed according to the mixing ratio shown in Table 1. The obtained impression material was left overnight at 23 ° C. and 50%, and evaluated under the same conditions. For this evaluation, 8 g of impression material powder was kneaded at a ratio of 20 g of water.

The gelation time was based on JIS-6505 (dental alginate impression material). The sauce was applied with an impression material paste of 27 × 20 × 10 mm on a glass plate, and one minute after the start of the kneading of the impression material, the glass plate was set upright and gelled. After gelation, measure the vertical length, the original length 2
The length is shown excluding 0 mm. The pressurized flow is shown as the ease of flow when weight is applied. 2 of the kneaded impression material paste
It was formed into a cylinder of 0φ × 31.5 mm, and was loaded with 120 g one minute after the start of kneading. The diameter of the disk after gelation was measured and defined as a pressurized flow.

The gel strength of the impression material was determined by measuring the compressive strength in accordance with JIS-6505. The change with time of the impression material was evaluated as an accelerated test by evaluating the physical properties after leaving the impression material sealed in an aluminum lamine bag in a 45 ° C. constant temperature bath for a predetermined period. After taking out from the thermostat, the impression material powder was returned to the temperature under the measurement conditions, and the same evaluation as above was performed. Table 1 shows the initial physical properties of the above impression materials and the results of the acceleration test. In each of the examples, the lean was able to be suppressed to 17 mm or less. In each case, the pressurized flow was 52 mm or more, and the hand during kneading was soft and easy to knead. Compressive strength is 0.35MPa
As mentioned above, it was considered that it had sufficient strength for practical use. In addition, as a result of the accelerated test, there was almost no change in sagging and compressive strength as compared with the initial values. We considered that a constant feeling of use was always obtained irrespective of the conditions and period of distribution and storage.

On the other hand, in Comparative Example 1, good results were obtained with respect to the initial value and the sag by the accelerated test, but the compressive strength by the accelerated test decreased, and 0.35 MPa after 4 weeks.
As a result, the strength was insufficient for practical use, and it could not be used. Further, in Comparative Example 2, the initial value of the sag was large, and further, the sagging was greatly increased by the accelerated test, and exceeded 4 mm after 4 weeks. Was concerned.

[0017]

[Table 1]

[0018]

According to the alginate impression material of the present invention, the flowability (drip) due to its own weight can be kept small while keeping the kneading feeling soft, and it is extremely easy to use. Further, since the alginate impression material of the present invention has physical properties that are stable over time, a constant feeling of use is always obtained irrespective of the distribution channel up to sale and the storage conditions after purchase, and conventionally, There is no failure caused by the adjustment of the water mixture ratio at the time of each use, or an improper water mixture ratio during kneading, and there is no fear of damage when the impression is removed from the mold. Can be used and work efficiency is improved.

Claims (3)

[Claims] An alginate impression material comprising xanthan gum and galactomannan. 2. The alginate impression material according to claim 1, which contains 0.05 to 0.8% by weight of xanthan gum. 3. The alginate impression material according to claim 1, which contains 0.05 to 10% by weight of galactomannan.