YY/T 0824-2011Dental calcium hydroxide pulp capping and lining materials (English PDF)

3.1 Calcium hydroxide cement

The main component is calcium hydroxide, which is a lining or pulp capping material that can react with organic chelating agents (such as salicylates).

Note: Cited from GB/T 9937.2-2008.

3.2 Direct pulp capping materials

Material placed directly on the exposed pulp of deep caries to protect the vitality of the pulp and promote the formation of restorative dentin.

3.3 Indirect pulp capping materials

A layer of material placed on the surface of dentin very close to the pulp to isolate external stimulation and protect the pulp.

3.4 Non-setting calcium hydroxide materials

Calcium hydroxide materials that cannot be cured when other lining, padding or filling materials are used on top of calcium hydroxide materials during clinical treatment operations.

5.1 General requirements

5.1.3 X-ray opacity (if the manufacturer claims that it has X-ray opacity) Test according to 6.3.

If the manufacturer claims that its product has X-ray opacity, its X-ray opacity shall be

at least equivalent to an aluminum plate of the same thickness as the material.

It cannot be 0.5 mm lower than the aluminum plate thickness specified by the manufacturer.

5.1.1 Appearance

Perform the test according to 6.1.

The powder shall be clean and free of impurities; the pigment distribution of the colored powder shall be uniform.

The liquid shall be clear, free of foreign impurities and sediment.

The paste has a uniform texture and is free of foreign impurities. The pigment distribution of the colored paste shall be uniform.

If the manufacturer has other instructions for the product, the product appearance shall be consistent with the manufacturer's product instructions.

5.1.2 Acid-soluble arsenic and lead content

Perform the test according to 6.2. Arsenic <= 2 mg/kg. Lead <= 100 mg/kg.

5.1.4 Calcium hydroxide content

The test value of calcium hydroxide content is allowed to have a relative error of ±5% with its product nominal value, that is, the testing value shall be within the range of "nominal value × (1 ± 0.05)".

Tested by one of the methods specified by the manufacturer in Appendix A or Appendix B. If neither of the above two methods is applicable, the manufacturer shall provide the test method.

Note: If the manufacturer's instructions give the calcium hydroxide content of one of the […]

6.2 Acid-soluble arsenic and lead content

6.2.1 Apparatus and reagents

6.2.1.1 Sample sieve, which has a pore size of 75 µm.

6.2.1.2 Electronic balance, which has an accuracy of 0.001 g.

6.2.1.3 Constant temperature box, which is capable of maintaining the temperature at (37 ± 1) °C.

6.2.1.4 Concentrated hydrochloric acid, 36% (mass fraction) (rho = 1.18 g/mL).

6.2.1.5 20% (volume fraction) dilute hydrochloric acid, which is obtained by injecting 20 mL of concentrated hydrochloric acid (6.2.1.4) into 80 mL water for dilution.

6.2.2 Specimen preparation

For solidifying materials, prepare the specimens according to the manufacturer's instructions.

For Category I Type 1 materials, place the blended materials in a clean plastic bag and seal the bag. Press the material in the bag with fingers to make it into a thin sheet. Place the sheet in a 37 °C incubator (6.2.1.3) for 24 hours. After 24 hours, grind the solidified material sheet with an agate mortar. Weigh 2 g of material that can pass through a 75 µm (200 mesh) sieve. Place it in a 150 mL flask. Add 50 mL of dilute hydrochloric acid (6.2.1.5). Cover the stopper. Shake the flask for 16 hours.

For Category I Type 2 materials, solidify the material into a thin sheet according to the manufacturer's instructions. Grind it with an agate mortar. Weigh 2 g of material that can pass through a 75 µm (200 mesh) sieve. Place it in a 150 mL flask. Add 50 mL of dilute hydrochloric acid (6.2.1.5). Put on the stopper. Shake the flask for 16 hours.

For non-curing materials, weigh 2 g of the material prepared according to the manufacturer's instructions. Place it in a 150 mL flask. Add 50 mL of dilute hydrochloric acid (6.2.1.5). Shake the flask for 16 hours.

Transfer the above prepared solution to a centrifuge tube and centrifuge for 10 minutes.

Aspirate the supernatant. Put it in a container. Cover the container tightly.

6.2.3 Method for determining arsenic content

Take an appropriate amount of the solution prepared according to 6.2.2. Determine the arsenic content according to the provisions of GB/T 23947.1-2009.

6.2.4 Method for determining lead content

Take an appropriate amount of the solution prepared according to 6.2.2. Determine the lead content by atomic absorption spectrometry or a method with equivalent or higher sensitivity.

6.2.5 Result determination

The arsenic and lead contents shall meet the requirements of 5.1.2.

6.3 X-ray radiopacity

Test according to 7.6 of YY 0271.2-2009. Make judgment on the results, which shall meet the requirements of 5.1.3.

6.4 pH

6.4.1 Instrument

6.4.1.2 Electronic balance, accuracy 0.01 g, or equivalent instrument

6.4.1.1 pH meter, accuracy 0.01

6.4.2 Specimen preparation

For curing materials, prepare the materials cured for (24 ± 1) h according to the manufacturer's instructions; crush it; weigh the materials that can pass through the 75 µm (200 mesh) sieve.

For non-curing materials, directly weigh the materials blended according to the manufacturer's instructions.

Dilute with distilled water or grade 3 water in accordance with GB/T 6682-2008, at a mass ratio of 1:10 (specimen: water); stir and dissolve for 5 minutes; prepare the test specimen to prepare for use.

6.4.3 Calibration

According to the instrument instructions, select appropriate standard buffer solution to calibrate the pH meter at the specified temperature or under the temperature compensation line conditions (6.4.1.1).

6.4.4 Determination

Set the sample to be tested, washing water, buffer solution to the specified temperature; adjust the temperature to calibrate the instrument at the same time.

After the instrument is calibrated, first wash the electrode with grade 3 water that meets

GB/T 6682-2008; then dry it with filter paper; insert the electrode into the sample to be tested, to immerse the electrode; wait for the pH value reading to stabilize and record it. Thoroughly clean the electrode and set it aside. Re-prepare the specimen; test it again It is tested in accordance with 7.9 of YY1042-2011; it shall meet the requirements of the sensitivity to ambient light in Table 1.

7.1 Overview

In addition to at least meeting the requirements of 7.3 and 7.4, the manufacturer may provide more information in accordance with the requirements of relevant regulations.

7.2 Packaging

Each component package shall be sealed; the packaging material shall not react with the contents or contaminate the contents.

7.3 Marking

Each outer package and/or inner package container shall be clearly marked with the following information:

a) Manufacturer's name and address;

b) Product name;

c) Product batch number, which can be traced back to the manufacturer's record number; production date and/or expiration date;

d) Mass (g) of powder or paste, volume (mL) of liquid; e) Storage conditions.

7.4 Product instructions and information

Each minimum retail package shall be accompanied by the manufacturer's instructions and information. In addition to complying with the general national regulations, the instructions and information shall at least include:

a) Product name;

b) Instructions for use and clinical application instructions;

c) Blending method and mixing ratio of each component;

d) Indicate the calcium hydroxide content, whether the material contains any therapeutic ingredients, and declare it in the material instructions;

e) Recommended storage conditions;

A.1 Apparatus and solution

A.1.1 Electronic balance: Accuracy of 0.001 g.

A.1.7 Ammonia test solution: Take 40 mL of concentrated ammonia solution and add water to 100 mL

A.1.5 Water: Grade 3 water in accordance with GB/T 6682-2008

A.1.4 Disodium ethylenediaminetetraacetic acid standard solution: Concentration of about 0.1 mol/L

A.1.3 Hydrochloric acid solution: Concentration of about 1.0 mol/L

A.1.2 Magnetic stirrer

A.1.6 Methyl red indicator solution: Concentration 0.1%

A.1.8 Ammonia-ammonium chloride

buffer chloride; add 20 mL of water to dissolve; add 35 mL of concentrated ammonia solution; use water to dilute to 10 mL.

A.1.9 Dilute magnesium sulfate solution: Take

2.3 g of magnesium sulfate; add water to dissolve to 100 mL A.1.10 Chrome black T indicator: Take 0.1 g of Chrome black T; add 10 g of sodium chloride; grind evenly.

A.2 Steps

Weigh about 1.0 g of the sample. Place it in a 150 mL beaker. Add an appropriate amount of hydrochloric acid solution (A.1.3) with a concentration of about 1.0 mol/L.

Stir and dissolve it with a magnetic stirrer (A.1.2) for 60 min. Filter and transfer to a 100 mL volumetric flask. Wash the beaker and filter residue 3 times. Transfer the washing solution to the volumetric flask. Use water to dilute to the mark. Shake well.

Accurately measure 10 mL of the above solution. Place it in a conical flask. Add 1 drop of methyl red indicator solution (A.1.6). Then add an appropriate amount of ammonia test solution (A.1.7), until the solution turns slightly yellow. Take another 10 mL of water. Add 10 mL of ammonia-ammonium chloride buffer solution (A.1.8), 1 drop of […]

B.1 Apparatus and solution

B.1.1 Electronic balance: accuracy 0.001 g.

B.1.5 Sodium hydroxide standard solution: concentration about 1.0 mol/L

B.1.4 Hydrochloric acid solution: concentration about 1.0 mol/L

B.1.2 pH meter: accuracy 0.01

B.1.3 Magnetic stirrer

B.2 Specimen preparation

For solidifying materials, solidify and crush the materials prepared according to the manufacturer's instructions. Weigh (1.0 ± 0.1) g of the sample that passes through a 75 µm (200 mesh) sieve in a 150 mL beaker. For non-solidifying materials, weigh (1.0 ± 0.1) g of the sample that is mixed according to the manufacturer's instructions in a 150 mL beaker. Add 35 mL of 1.0 mol/L hydrochloric acid solution (B.1.4). Stir and dissolve for 60 min. Add 30 mL of distilled water or grade 3 water in accordance with GB/T 6682-2008. Stir evenly. Prepare the test solution.

B.3 Test steps

Use sodium hydroxide standard solution (B.1.5) to slowly titrate the test solution under magnetic stirring conditions. Use a pH meter (B.1.2) to test the pH value of the solution.

When the pH meter shows that the pH jumps to above 8, stop the titration immediately.

Record the volume of the sodium hydroxide standard solution consumed, which is recorded as V1.

At the same time, weigh the same amount of control reagent to prepare a blank test.

Record the volume of the sodium hydroxide standard solution consumed in the blank test, which is recorded as V0.

The control reagent is a material provided by the manufacturer, in which the calcium hydroxide in the product is replaced with silicon dioxide or a material that does not contain calcium. Calculate the content of calcium hydroxide according to formula (B.1): […]