Dental alginate impression material

Abstract

According to an aspect of the present invention, a dental alginate impression material includes an alginate, calcium sulfate, and an aminocarboxylic acid compound.

Claims

1. A dental alginate impression material comprising: a main material including an alginate, an aminocarboxylic acid compound, and water; and a hardening material including calcium sulfate and a nonaqueous dispersion medium, wherein the nonaqueous dispersion medium is a polyether having at least three hydroxyl groups, the polyether having at least three hydroxyl groups having a viscosity at 23 C. in a range from 100 mPa.Math.s to 4000 mPa.Math.s.

2. The dental alginate impression material according to claim 1, wherein the main material contains the alginate at a content ranging from 3% to 10% by mass and contains the aminocarboxylic acid compound at a content ranging from 0.01% to 2% by mass; and the hardening material contains the calcium sulfate at a content ranging from 65% to 85% by mass.

3. The dental alginate impression material according to claim 1, wherein the main material and the hardening material each have viscosities ranging from 4 Pa.Math.s to 40 Pa.Math.s at 23 C.

4. The dental alginate impression material according to claim 1, wherein the hardening material further includes a zinc oxide having a number average particle diameter that is less than or equal to 100 nm.

5. The dental alginate impression material according to claim 1, wherein a volume ratio of the hardening material with respect to the main material is from 0.25 to 0.5.

Description

EXAMPLES

(1) In the following, the present invention will be described in detail by way of examples and comparative examples. Note, however, that the present invention is not limited to these examples.

(2) [Two-Material Type]

Examples 1-1 to 1-11, Comparative Examples 1-1 to 1-4

(3) Alginate, trisodium ethylenediaminetetraacetate (EDTA.Math.3Na), polyoxyalkylene alkyl ether (POAAE), and sodium pyrophosphate were mixed together at the mix ratios indicated in Table 1 below to obtain the main material.

(4) Calcium sulfate, glycerol propoxylate, zinc oxide powder, magnesium hydroxide, potassium fluorotitanate, and fumed silica were mixed together at the mix ratios indicated in Table 1 to obtain the hardening material.

(5) The following is information on the raw materials listed in Table 1.

(6) Sodium alginate: Duck Algin NSPM (manufactured by Kikkoman Biochemifa Co., Ltd.)

(7) Potassium alginate: Duck Algin K (manufactured by Kikkoman Biochemifa Co., Ltd.)

(8) POAAE: Naroacty CL (manufactured by Sanyo Chemical Industries, Ltd.)

(9) Glycerol propoxylate: G-300 (manufactured by Adeka Corporation)

(10) Zinc oxide powder A: number average particle diameter 20 nm

(11) Zinc oxide powder B: number average particle diameter 100 nm

(12) Also, the method of measuring the number average particle diameter of the zinc oxide powder is described below.

(13) <Number Average Particle Diameter of Zinc Oxide Powder>

(14) The number average particle diameter of the zinc oxide powder was measured by a laser dynamic light scattering analyzer ELS-Z (manufactured by Otsuka Electronics Co., Ltd.) using water as a dispersion medium.

(15) Next, the viscosities of the main material and the hardening material were measured.

(16) <Viscosity of Main Material and Hardening Material>

(17) The viscosities of the main material and the hardening material at 23 C. were measured using an E type viscometer RE-85 (manufactured by Toki Sangyo Co., Ltd.), under conditions where the cone angle was 3 and the shear rate was 24 s.sup.1 (rotational speed was 12 rpm).

(18) Next, the compression strength of the cured product, the initial setting time, the storage stability of the main material, and the impression accuracy were evaluated.

(19) <Compressive Strength of Cured Product>

(20) The main material and the hardening material were weighted out on kneader paper at volume ratio indicated in Table 1 and kneaded for 30 seconds with a spatula, and the compressive strength of the cured product was measured according to JIS T6505.

(21) <Initial Setting Time>

(22) The main material and the hardening material were weighed out on kneader paper at the volume ratio indicated in Table 1 and kneaded for 30 seconds with a spatula, and the initial setting time was measured according to JIS T6505. Note that the measurement of the initial setting time was performed in 5-second units.

(23) <Storage Stability of Main Material>

(24) After storing the main material for 1 week in an environment of 60 C. and 100% RH, the viscosity of the main material at 23 C. was measured in the same manner as described above. Then, the rate of change in the viscosity of the main material was calculated using the following formula:
[(Viscosity After Storage)(Initial Viscosity])/(Initial Viscosity)100

(25) <Impression Accuracy>

(26) The main material and the hardening material were weighed out on kneaded paper at the volume ratio indicated in Table 1 and kneaded for 30 seconds with a spatula, and the impression accuracy was evaluated by the compatibility test with gypsum according to JIS T 6505.

(27) Table 1 indicates the evaluation results of the compressive strength of the cured product, the initial setting time, the storage stability of the main material, and the impression accuracy.

(28) TABLE-US-00001 TABLE 1 UNIT OF MIX RATIO: MASS % COMPARATIVE EXAMPLE 1 EXAMPLE 1 1 2 3 4 5 6 7 8 9 10 11 1 2 3 4 MAIN SODIUM ALGINATE 6 3 MAT- POTASSIUM ALGINATE 6 6 3 3 10 6 6 6 6 6 2 11 6 6 ERIAL WATER 91.8 91.8 91.8 91.8 94.89 85.97 91.8 91.8 91.8 91.8 91.8 95.9 86.9 91.9 91.9 EDTA3Na 0.1 0.1 0.1 0.1 0.01 2 0.1 0.1 0.1 0.1 0.1 POAAE 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 SODIUM 0.1 0.1 0.1 0.1 0.1 0.03 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 PYROPHOSPHATE TOTAL 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 HARD- -CALCIUM SULFATE 70 70 70 70 70 70 85 65 70 70 70 70 70 90 60 ENING HEMIHYDRATE MATE- GLYCEROL 25 25 25 25 25 25 13 26 21 25 25 25 25 8 31 RIAL PROPOXYLATE ZINC OXIDE POWDER A 1 0.1 ZINC OXIDE POWDER B 5 MAGNESIUM 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 HYDROXIDE POTASSIUM FLUOROTITANATE 2 2 2 2 2 2 0.5 2 2 2 2 2 2 0.5 2 FUMED SILICA 2 1 2 2 2 2 0.5 6 1 1.9 2 2 2 0.5 6 TOTAL 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 MAIN MATERIAL 5 5 8 5 4 38 5 5 5 5 5 2 51 6 6 VISCOSITY [Pa .Math. s] HARDENING MATERIAL VISCOSITY [Pa .Math. s] 6 7 6 6 6 6 40 6 6 6 6 6 6 62 5 VOLUME RATIO 4:1 4:1 4:1 4:1 4:1 4:1 4:1 4:1 4:1 4:1 2:1 4:1 4:1 4:1 4:1 (MAIN MATERIAL:HARD- ENING MATERIAL) COMPRESSIVE STRENGTH 0.5 0.8 0.6 0.4 0.5 0.6 0.5 0.5 0.7 0.7 0.5 0.3 0.7 0.6 0.3 OF CURED PRODUCT [MPa] INITIAL SETTING TIME [s] 90 80 100 90 80 70 90 90 70 75 90 110 60 50 70 MAIN MATERIAL 5 3 4 6 8 5 7 2 2 4 6 90 96 84 93 STORAGE STABILITY [%] IMPRESSION ACCURACY [m] 20 20 20 20 20 20 20 20 20 20 20 20 50 50 20

(29) It can be appreciated from Table 1 that the alginate impression materials of Examples 1-1 to 1-11 have long initial setting times and their main materials have high storage stability.

(30) In contrast, the alginate impression materials of Comparative Examples 1-1 to 1-4 contain no aminocarboxylic acid, and as a result, their main materials have lower storage stability.

(31) [One-Material Type]

Examples 2-1 to 2-7, Comparative Examples 2-1 to 2-3

(32) Alginate, trisodium ethylenediaminetetraacetate (EDTA.Math.3Na), calcium sulfate, zinc oxide powder, magnesium hydroxide, potassium fluorotitanate, polyoxyalkylene alkyl ether (POAAE), liquid paraffin, sodium pyrophosphate and diatomaceous earth were mixed together at the mix ratio indicated in Table 2 below to obtain the alginate impression material.

(33) Next, the flow value of the alginate impression material was measured.

(34) <Flow Value>

(35) 16.8 g of the alginate impression material was weighed out and placed in a rubber cup after which 40 cc of water was weighed out and poured into the rubber cup, and the alginate impression material and water were kneaded for 30 seconds with a spatula to obtain a kneaded material. Next, the kneaded material was filled in a metal ring having an inner diameter of 35 mm and a height of 50 mm, and only the kneaded material was quickly extruded onto a glass plate and cured. The spread of the kneaded material due to its own weight, that is, the diameter of the cured product was measured as a surrogate characteristic of sagability to represent the flow value.

(36) Next, the compressive strength, the initial setting time, the storage stability, and the impression accuracy of the cured product were evaluated.

(37) <Compressive Strength of Cured Product>

(38) 16.8 g of the alginate impression material was weighed out and placed in a rubber cup after which 40 cc of water was weighted out and poured into the rubber cup, and the alginate impression material and water were kneaded for 30 seconds with a spatula and cured. The compressive strength of the cured product was measured according to JIS T 6505.

(39) <Initial Setting Time>

(40) 16.8 g of the alginate impression material was weighed out and placed in a rubber cup after which 40 cc of water was weighed out and poured into the rubber cup, and the alginate impression material and water were kneaded for 30 seconds with a spatula and cured. The initial setting time of the alginate impression material was measured according to JIS T 6505. Note that the measurement of the initial setting time was performed in 5-second units.

(41) <Storage Stability>

(42) After storing the alginate impression material for 1 week under an environment of 60 C. and 100% RH, the flow value of the alginate impression was measured, and a change in the flow value of the alginate impression material was calculated using the following formula:
(Flow Value After Storage)(Initial Flow Value)

(43) <Impression Accuracy>

(44) 16.8 g of the alginate impression material was weighed out and placed in a rubber cup after which 40 cc of water was weighed out and poured into the rubber cup, the alginate impression material and water were kneaded for 30 seconds with a spatula, and the impression accuracy was evaluated by the compatibility test with gypsum according to JIS T 6505.

(45) Table 2 indicates the evaluation results of the compressive strength of the cured product, the initial setting time, the storage stability, and the impression accuracy.

(46) TABLE-US-00002 TABLE 2 UNIT OF MIX RATIO: MASS % COMPARATIVE EXAMPLE 2 EXAMPLE 2 1 2 3 4 5 6 7 1 2 3 SODIUM ALGINATE 12 12 6 7 12 12 12 POTASSIUM ALGINATE 12 6 15 12 EDTA3Na 0.1 0.1 0.1 0.1 0.01 2 0.1 -CALCIUM SULFATE 12 6 8 15 45 12 HEMIHYDRATE CALCIUM SULFATE 12 12 6 8 12 12 DIHYDRATE ZINC OXIDE POWDER A 1 1 MAGNESIUM HYDROXIDE 1 1 1 1 1 1 1 1 1 1 POTASSIUM 1 1 1 1 1 2 1 1 1 1 FLUOROTITANATE POAAE 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 LIQUID PARAFFIN 1 1 1 1 1 1 1 1 1 1 SODIUM PYROPHOSPHATE 2 2 2 2 2 0.3 2 2 2 2 DIATOMACEOUS EARTH 70.6 69.6 70.6 70.6 71.69 63.4 37.6 70.7 69.7 70.7 TOTAL 100 100 100 100 100 100 100 100 100 100 FLOW VALUE [mm] 52 51 49 50 55 45 58 0.5 0.8 0.6 COMPRESSIVE STRENGTH 0.5 0.8 0.6 0.4 0.5 0.6 0.8 120 80 100 OF CURED PRODUCT [MPa] INITIAL SETTING TIME [s] 120 130 125 135 140 125 130 51 52 50 STORAGE STABILITY [mm] +2 +3 +1 +5 +2 +2 +4 +22 +15 +18 IMPRESSION 50 20 20 20 20 20 50 50 20 20 ACCURACY [m]

(47) It can be appreciated from Table 2 that the alginate impression materials of Examples 2-1 to 2-7 have long initial setting times and high storage stability.

(48) In contrast, the alginate impression materials of Comparative Examples 2-1 to 2-3 contain no aminocarboxylic acids and therefore have lower storage stability.