Premixed injectable deciduous tooth root canal filling material as well as preparation method and application thereof
By preparing a premixed injectable root canal filling material for primary teeth, the problem of mismatch between biocompatibility, antibacterial properties and absorption rate of existing root canal filling materials for primary teeth was solved, achieving optimized absorption of the material and improving the eruption of permanent teeth.
Patent Information
- Application Number
- CN202511400020.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-09-28
- Publication Date
- 2025-12-19
AI Technical Summary
Existing root canal filling materials for deciduous teeth are insufficient in terms of biocompatibility, antibacterial properties, and anti-inflammatory effects, and their absorption rate does not match the physiological differences between deciduous and permanent teeth, thus affecting the eruption of permanent teeth.
A premixed injectable root canal filling material for deciduous teeth was prepared by combining α-calcium sulfate hemihydrate, X-ray blocking components, calcium oxide, calcium salt, polyphosphate, sodium chloride, antibacterial agent and biological polyphenol to prepare a bioceramic paste for root canal treatment of deciduous teeth.
The material's absorption rate was optimized, its biocompatibility and antibacterial properties were improved, and it matched the microenvironment of deciduous tooth roots, which is beneficial to the eruption of permanent tooth germs and the efficacy of root canal treatment for deciduous teeth.
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Figure CN121154428A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of biomaterials technology, specifically to a premixed injectable root canal filling material for deciduous teeth, its preparation method, and its application. Background Technology
[0002] Dental caries and dental trauma are global public health problems. With improved living standards and advancements in dental technology, conservative treatment of diseased deciduous teeth is receiving increasing attention. Untreated carious deciduous teeth can lead to pulp and periapical lesions. Once pulpitis occurs, root canal treatment is the best way to preserve the deciduous tooth. Due to anatomical and developmental differences between permanent and deciduous teeth, most root canal filling materials for permanent teeth are not suitable for deciduous teeth. Ideal root canal filling materials for deciduous teeth should meet the following characteristics: biocompatibility with periapical tissues and the successor permanent tooth germ; similar resorption rate to deciduous tooth roots; radiopaque; dimensionally stable; easy to apply; readily absorbed when extruded from the root canal; antibacterial and anti-inflammatory; less likely to stain teeth; and resorption rate comparable to that of deciduous tooth roots.
[0003] Currently widely used root canal filling materials for primary teeth, such as calcium hydroxide cement (CH), zinc oxide-eugenol cement (ZOE), iodoform cement, and combinations of iodoform with CH or ZOE, still have some drawbacks in terms of biocompatibility, antibacterial and anti-inflammatory properties, and degradation performance. Calcium hydroxide is absorbed faster than the physiological absorption of primary tooth roots, is permeable to tissue fluid, has radiolucent properties, and exhibits a hollow tube effect. Zinc oxide-eugenol can trigger chronic inflammatory responses in the periapical tissues, is absorbed more slowly than in primary tooth roots, causes a foreign body reaction in the periapical tissues, and can lead to ectopic eruption of permanent teeth. The absorption rate of a mixture of calcium hydroxide and iodoform is faster than that of primary teeth. Therefore, no single root canal filling material currently used in primary teeth can meet all the ideal physical, chemical, antibacterial, and biological requirements, and new root canal filling materials for primary teeth need to be developed to improve the success rate of root canal treatment in primary teeth.
[0004] Currently, self-curing calcium silicate-based ceramic cement is a relatively ideal root canal filling material, possessing good biomineralization properties, biocompatibility, and certain antibacterial properties. However, calcium silicate cement is almost non-absorbable and cannot be used for root canal treatment of deciduous teeth.
[0005] Calcium sulfate hemihydrate, when cured, is often used as a curing agent in bone repair materials, exhibiting good absorbability and biocompatibility. Calcium phosphate saline cement, with hydroxyapatite as its main growth component, also possesses absorbability and excellent biocompatibility. Through component optimization, the reaction product can generate calcium hydroxide, ensuring the final product remains alkaline, thus improving the acidic microenvironment around the periapical region of deciduous teeth. Biological polyphenols possess certain anti-inflammatory effects; chlorhexidine, a classic oral antibacterial agent, exhibits prolonged action and reduced toxicity when combined with the aforementioned calcium salts. In view of the above, this invention, through the optimized combination of the above components, yields the present invention. Summary of the Invention
[0006] The purpose of this invention is to solve the problems of excessively rapid absorption of calcium hydroxide-based primary tooth root canal filling materials, excessively slow absorption of zinc oxide-eugenol cement affecting the eruption of subsequent permanent teeth, and the insufficient anti-inflammatory, antibacterial, and biocompatibility of current primary tooth root canal filling materials. This invention provides a premixed injectable primary tooth root canal filling material, its preparation method, and its application.
[0007] To achieve the above objectives, this invention discloses a method for preparing a premixed injectable root canal filling material for deciduous teeth, comprising the following steps:
[0008] S1, Weigh the solid powder mixture: α-calcium sulfate hemihydrate, X-ray blocking components, calcium oxides and calcium salts, polyphosphates, sodium chloride, antibacterial agents and bio-polyphenols;
[0009] S2, add the water-soluble non-aqueous liquid to the solid powder mixture in step S1 to obtain a mixed paste, and ball mill the mixed paste to obtain a bioceramic paste.
[0010] The mass percentage of the solid powder raw materials in step S1 is as follows: 60-80 wt% α-calcium sulfate hemihydrate, 10-30 wt% X-ray blocking component, 0-10 wt% calcium oxide and calcium salt, 0-20% polyphosphate, 0.9% sodium chloride, and 0-0.002 wt% antibacterial agent.
[0011] In step S1, the X-ray blocking component is either iodoform or barium sulfate.
[0012] In step S1, the calcium oxide is calcined calcium oxide, the calcium salt is calcium hydrogen phosphate, and the polyphosphate is trisodium polyphosphate, trisodium metapolyphosphate, or tetracalcium polyphosphate.
[0013] In step S1, the antibacterial agent and the bio-polyphenol are chlorhexidine or brown algae polyphenols, and the mass ratio of chlorhexidine to brown algae polyphenols is 0 to 1:3.
[0014] In step S2, the water-soluble non-aqueous liquid is glycerol or polyethylene glycol-400 / 600.
[0015] In step S2, the liquid-to-powder ratio of the mixture of water-soluble non-aqueous liquid and solid powder is 0.5 mL / g.
[0016] In step S2, the ball milling speed is 200 r / min and the ball milling time is 24 h.
[0017] The present invention also discloses a premixed injectable primary tooth root canal filling material prepared by the above preparation method and the application of this premixed injectable primary tooth root canal filling material in the preparation of primary tooth root canal treatment materials.
[0018] Compared with the prior art, the beneficial effects of the present invention are as follows:
[0019] 1. This invention discloses for the first time the structural composition of a primary tooth root filling material, which has a more optimized absorption rate compared to the calcium hydroxide-based and zinc oxide-eugenol cement primary tooth root filling materials currently used in clinical practice.
[0020] 2. This invention uses a combination of biological polyphenols and antibacterial agents. By adjusting the ratio of the two, the antibacterial properties are achieved while improving the biocompatibility of the materials.
[0021] 3. The bioceramic in this invention has antibacterial, anti-inflammatory, absorbable, and biocompatible properties, which match the microenvironment of deciduous tooth root resorption and are beneficial to the eruption of permanent tooth germs and the efficacy of deciduous tooth root canal treatment. Attached Figure Description
[0022] Figure 1 The invented paste and its radiometric image after filling the root canal;
[0023] Figure 2 X-ray diffraction pattern of calcium sulfate hemihydrate powder;
[0024] Figure 3 These are the initial and complete solidification times;
[0025] Figure 4 The opacity of each group and its equivalence to the aluminum wedge;
[0026] Figure 5 Comparison of the relative X-ray densities of each group of pastes with the third-order aluminum wedge;
[0027] Figure 6 X-rays of the paste loaded in the syringe and the root canal filled with the paste showed that it was less transparent than the tooth root;
[0028] Figure 7 All experimental groups had a flowability exceeding 17 mm, conforming to the ISO standard (ISO 6876-2012) Dentistry—Root canal sealing materials international standard.
[0029] Figure 8 The pH value of the paste in water changed over time, from 30 minutes to 28 days;
[0030] Figure 9 The pH value of the paste in PBS changed over time, from 30 min to 28 days;
[0031] Figure 10 For the evaluation of antibacterial and biocompatibility of Example 1 of the present invention, (a) are the results of bacterial plate smear method for each group; (b) are the colony-forming units / ml of Enterococcus faecalis in the culture medium in contact with the paste and the control group; (c) are the cell viability of SD-BMSCs after 1, 4 and 7 days of culture in the extract after soaking in the paste for 24 h at different dilutions, and the control group refers to the culture medium without the material extract; (d) are the morphological culture of cells in the paste group in cell culture medium diluted 1:3 at 1 day, 4 days and 7 days, the cell nuclei were stained by DAPI (blue) and actin was stained by TRITC Phalloidin (red).
[0032] Figure 11 The images show the XRD pattern (a) and FTIR pattern (b) of the slurry after 48 hours of hydration of the product in Example 1 of this invention.
[0033] Figure 12 The image shows the SEM morphology of the slurry after 48 hours of hydration; where (c2) is a magnified image of (c1); (c3) is a cross-sectional view of the hydrated slurry; and (c4) is a magnified image of (c3).
[0034] Figure 13 XRD pattern of slurry soaked in SBF for 7 days;
[0035] Figure 14 The image shows the SEM morphology of the slurry soaked in SBF for 7 days, where (e1) is the surface of the slurry and (e2) is a magnified image of (e1).
[0036] Figure 15 This is a schematic diagram of the in vitro degradation evaluation method for paste curing in Example 1 of the present invention;
[0037] Figure 16 The cumulative weight loss over 4 weeks in vitro;
[0038] Figure 17 To visually observe the degradation and tissue response of different implant materials at 2 weeks, 1 month, and 2 months post-surgery, the white arrows (b1, b3, b5) indicate the degraded materials.
[0039] Figure 18Histological results of tissue sections at 2 weeks, 1 month, and 2 months; white arrows indicate degraded material. Detailed Implementation
[0040] The above-mentioned and other technical features and advantages of the present invention will be described in more detail below with reference to the accompanying drawings.
[0041] Example 1
[0042] A method for preparing a premixed injectable root canal filling material for deciduous teeth, comprising the following specific steps:
[0043] 1. Mix the following solid powder raw materials in the following proportions: calcium sulfate hemihydrate (its structure is as follows) Figure 2 (As shown) 60wt%, iodoform 29wt%, calcium oxide and dicalcium phosphate (calcium-phosphorus molar ratio 2.5) 10wt%, and sodium chloride 0.9% are placed in a container.
[0044] 2. Based on the total weight of the powder in step 1, measure out PEG 400 liquid at a liquid-to-powder ratio of 0.5 mL / g and add it to the container containing the powder to mix.
[0045] 3. Transfer the mixed paste obtained in step 2 to a zirconia ball mill jar and ball mill at 200 r / min for 24 h.
[0046] 4. The paste obtained in step 3 is placed into a medical syringe, sterilized with cobalt-60, and used clinically for root canal treatment of deciduous teeth.
[0047] Example 2
[0048] A method for preparing a premixed injectable root canal filling material for deciduous teeth, comprising the following specific steps:
[0049] 1. Place the following solid powder raw materials in a container according to the following proportions: 80wt% α-hemihydrate calcium sulfate, 19wt% barium sulfate, 0.002wt% chlorhexidine and brown algae polyphenol (chlorhexidine: brown algae polyphenol = 1:2), and 0.9% sodium chloride.
[0050] 2. Based on the total weight of the powder in step 1, measure out PEG 400 liquid at a liquid-to-powder ratio of 0.5 mL / g and add it to the container containing the powder to mix.
[0051] 3. Transfer the mixed paste obtained in step 2 to a zirconia ball mill jar and ball mill at 200 r / min for 24 h.
[0052] 4. The paste obtained in step 3 is placed into a medical syringe, sterilized with cobalt-60, and used clinically for root canal treatment of deciduous teeth.
[0053] Example 3
[0054] A method for preparing a premixed injectable root canal filling material for deciduous teeth, comprising the following specific steps:
[0055] 1. Place the following solid powder raw materials in a container according to the following proportions: 40wt% α-hemihydrate calcium sulfate, 20wt% barium sulfate, 20wt% polytetraphosphate, 20wt% sodium trimetaphosphate, 0.002wt% chlorhexidine and brown algae polyphenol (chlorhexidine: brown algae polyphenol = 1:2), and 0.9% sodium chloride.
[0056] 2. Based on the total weight of the powder in step 1, measure out PEG 400 liquid at a liquid-to-powder ratio of 0.5 mL / g and add it to the container containing the powder to mix.
[0057] 3. Transfer the mixed paste obtained in step 2 to a zirconia ball mill jar and ball mill at 200 r / min for 24 h.
[0058] 4. The paste obtained in step 3 is placed into a medical syringe, sterilized with cobalt-60, and used clinically for root canal treatment of deciduous teeth.
[0059] The properties of the premixed injectable deciduous tooth root canal filling material obtained in the examples were tested as follows:
[0060] I. Evaluation of the setting time of the premixed injectable primary tooth root canal filling material obtained in Example 1
[0061] The injectable calcium silicate-based self-curing bioceramic material for root canal treatment obtained in Example 1 was evaluated according to ISO standard (ISO 6876-2012) Dentistry—Root canal sealing materials. The material was injected into a stainless steel mold with a diameter of 10 mm and a height of 1 mm and maintained in an environment at (37±1)℃ and relative humidity >95%. Using a Gilmore probe with a flat tip diameter of 2.0±0.1 mm and a pressure of A100±0.5 g, the time from the initial setting to the point where the probe could no longer leave an indentation was recorded as the setting time. The initial setting time of the paste was 4-5 hours, and the complete setting time was 11-12 hours, meeting the ISO 6876-2012 standard of less than 72 hours. The results are as follows: Figure 3 As shown.
[0062] II. Evaluation of the X-ray radioactivity of the premixed injectable deciduous tooth root canal filling material obtained in Example 1
[0063] A paste was prepared by adding different concentrations of iodoform according to Example 1, and its radiometric opacity was measured. The radiometric opacity was evaluated according to ISO 6876:2012. X-ray images of samples with a diameter of 10 mm × 1 mm thickness were obtained at a focal length of 400 mm using a fluorescent plate digital system (VistaScan, Dürr Dental GmbH & Co. KG, Germany) at 70 kV and 8 mA for 0.2 s exposure. Simultaneously, aluminum stepped wedges with thicknesses ranging from 1 mm to 8 mm were exposed. The standard wedge shape was stepped, starting at 1 mm with each step increasing by 1 mm. The wedge size was 50 mm × 5 mm, with thicknesses ranging from 1 to 10 mm. The radiometric opacity of the paste was converted to the thickness of the aluminum plate based on the grayscale of the images obtained using Adobe Photoshop CC 2021. Five samples were measured for each sealant group, and the average value was taken. The appropriate proportions of each component were selected to prepare the paste based on the curing time and radiometric opacity. When the iodoform content of the paste was greater than 30 wt%, it was greater than 3 mm of aluminum plate thickness, conforming to ISO 6876:2012 standard. Results are as follows: Figure 4-6 As shown.
[0064] III. Detection of the flowability of the premixed injectable deciduous tooth root canal filling material obtained in Example 1
[0065] Prepare two glass plates, each measuring 40×40×5 mm³ and weighing approximately 20 g. Place 0.05 ml of the paste in the center of one glass plate. After 3 minutes, place the other glass plate directly onto the paste, applying a total weight of 120 mg, causing the paste to compress. Allow the apparatus to stabilize for 10 minutes, then measure the minimum and maximum diameter of each sample using a ruler in millimeters. Determine the average diameter (in millimeters) for each slurry. The test was repeated five times. According to ISO 6876:2012, the standard recommends a flow rate of not less than 17 mm. The results showed that the flow rate of all groups was greater than 17 mm. Figure 7 (As shown).
[0066] IV. pH Evaluation of the Premixed Injectable Primary Tooth Root Canal Filling Material Obtained in Example 1
[0067] The paste was injected into a circular polytetrafluoroethylene mold with an inner diameter of 15 mm and a height of 2 mm, and stored at 37°C and 100% humidity for 48 hours. Afterward, each sample was immersed in a centrifuge tube containing 10 mL of deionized water or PBS buffer, the main components of which were Na₂HPO₄, NaCl, and NaH₂PO₄. The samples were then stored at 37°C for 30 minutes, 1 hour, 1 day, 7 days, and 28 days throughout the experimental intervals. At each time interval, a previously calibrated digital pH meter (SevenCompact) was used. TMThe pH of the solution was measured using a centrifuge tube (S210, Mettler Toledo, Switzerland). The solution in each centrifuge tube was replaced after each measurement. Results showed that the pH in deionized water stabilized at 11-12 within 7 days, decreasing over time to around 7. Figure 8 In PBS solution, the pH gradually rises to 11 within 1 day, remains around 7 for 7 days, and then decreases to 5-6 over time. Figure 9 (As shown).
[0068] V. Evaluation of the antibacterial properties of the premixed injectable deciduous tooth root canal filling material obtained in Example 1
[0069] The calcium sulfate-based self-curing bioceramic material obtained in Example 1, cured for 48 hours, was anaerobically cultured with *E. faecalis* (ATCC 29212) in brain heart and brain broth (BHI, Darmstadt, Germany) for 24 hours. The results showed that the material exhibited good antibacterial properties. Within 24 hours, the sample could kill 45% of *E. faecalis*. The CFU / mL count (colony forming units / mL) of *E. faecalis* in the experimental group and the control group were 335 × 10⁻⁶. 6 CFU / mL and 150×10 6 The CFU / mL levels showed a statistically significant difference (P<0.05). Figure 10 (a) and Figure 10 As shown in (b).
[0070] VI. Biocompatibility Test of the Premixed Injectable Primary Tooth Root Canal Filling Material Obtained in Example 1
[0071] The calcium sulfate-based self-curing bioceramic material obtained in Example 1, cured for 48 hours, was immersed in cell culture medium. The resulting extracts were diluted to 1:3, 1:5, and 1:10, respectively, and then co-cultured with bone marrow stromal stem cells. Results showed that cells in the experimental groups (extracts diluted 1:3, 1:5, and 1:10) gradually proliferated and grew within 7 days. At days 1, 4, and 7, the cell viability in all groups cultured with the diluted extracts was higher than that in the control group (P<0.05). The results are as follows... Figure 10 (c) and Figure 10 As shown in (d).
[0072] VII. The premixed injectable deciduous tooth root canal filling material obtained in Example 1 induces the formation of bone-like apatite in simulated body fluid.
[0073] The calcium sulfate-based self-curing bioceramic material obtained in Example 1, cured for 48 hours, was immersed in SBF for 7 days. XRD spectra of the cured paste surface showed that diffraction peaks at 2θ = 11.55°, 20.84°, 29.19°, 31.34°, and 33.45° matched the standard diffraction peaks of calcium sulfate dihydrate (CSD, PDF No. 36-0432). Besides the predominantly formed calcium sulfate dihydrate, diffraction peaks of varying intensities at 2θ = 25.9°, 31.7°, 34.1°, 39.8°, 46.7°, and 49.5° also appeared, consistent with the standard peaks of hydroxyapatite (HA, PDF No. 09-0432). Scanning electron microscopy revealed that, in addition to orthorhombic calcium sulfate crystals, needle-like hydroxyapatite crystals were also present on the surface and between the pores. Figure 11-14 As shown.
[0074] 8. Evaluation of the in vitro degradability of the premixed injectable primary tooth root canal filling material obtained in Example 1
[0075] The paste was placed into a circular PTFE mold with an inner diameter of 10 mm and a height of 1 mm and stored at 100% humidity and 37°C for 48 hours. The sample was then removed and dried in an oven at 60°C, accurately weighed (W0), and then immersed in 1 mL of PBS (pH = 7.4). The sample was shaken on a shaker at 60 rpm to simulate the dynamic environment in vivo. After 1, 2, 3, and 4 weeks, the sample was rinsed with deionized water and dried at 60°C to determine the weight loss. The PBS was replaced after each weighing. The formula for calculating the weight loss is: L = (W0 - W) / W0 × 100%, where W0 is the mass before degradation and W is the mass after degradation at different times. The weight of the paste sample was weighed before and after in vitro immersion in PBS to monitor degradation (e.g., ...). Figure 15 ). Figure 16 The data shows the cumulative weight loss of the sample as soaking time increases. After 28 days, the cumulative weight loss of the paste sample reached 45%. In the first week, the weight loss was approximately 30%, while in the following weeks, the weight loss rate was only 5%. The weight loss rate has been significantly reduced.
[0076] IX. In vivo degradation experiment of the premixed injectable deciduous tooth root canal filling material obtained in Example 1
[0077] The calcium sulfate-based self-curing bioceramic material obtained in Example 1, cured for 48 hours, was implanted into the subcutaneous tissue of the back of healthy adult male SD rats. Two weeks, one month, and two months post-surgery, the rats were euthanized painlessly using an overdose of anesthesia. The implanted material and surrounding soft tissues, including the skin, were removed and fixed in paraformaldehyde solution. After dehydration, all soft tissues were embedded in paraffin wax perpendicular to the skin section (5 micrometers thick). Tissue sections were taken from the material group and the control group at different time points.
[0078] Macroscopic observation of tissue reactions in different groups revealed that in the second week post-surgery, neither the material group nor the control group showed redness, exudation, bleeding, or tissue rejection. However, vasodilation was observed in both groups, with the material group showing more pronounced vasodilation than the control group. One month post-surgery, a small amount of residual material was visible after degradation in the experimental group, while no significant vasodilation was observed in either the control or experimental groups. Two months post-surgery, the degraded material was no longer clearly visible to the naked eye; only the surgical site appeared darker than the surrounding tissue. Figure 17 At two weeks, one month, and two months post-surgery, HE-stained histological examination of the material group and the control group showed that, at two weeks post-surgery, the experimental group had significantly more inflammatory cells infiltrating at the junction of the material and tissue compared to the control group. At one month, the number of infiltrating cells in both the control and material groups decreased, with cells mainly concentrated at the junction with the material, although the cell count remained higher than in the control group. At two months, the number of infiltrating cells at the incision site in the control group was similar to that of normal tissue, while in the experimental group, no obvious sample material was observed under the microscope, but circular tissue formed by residual material surrounded by cells could be found at the material implantation site. Figure 18 ).
[0079] The above description is merely a preferred embodiment of the present invention and is illustrative rather than restrictive. Those skilled in the art will understand that many changes, modifications, and even equivalents can be made within the spirit and scope defined by the claims of the present invention, all of which will fall within the protection scope of the present invention.
Claims
1. A method for preparing a premixed injectable primary root canal filling material, characterized in that, The method comprises the following steps: S1, weighing solid powder mixture: α calcium sulfate hemihydrate, X-ray blocking component, calcium oxide and calcium salt, sodium chloride, polyphosphate, antibacterial agent and biological polyphenol; S2, adding water-soluble non-aqueous liquid to the solid powder mixture in step S1 to obtain a mixed paste, and ball milling the mixed paste to obtain an injectable primary tooth root canal filling material.
2. A method of preparing a pre-mixed injectable primary root canal filling material as claimed in claim 1, wherein, In step S1, the mass percentage of the solid powder raw material is: α calcium sulfate hemihydrate 50-90wt%, X-ray blocking component 10-30wt%, calcium oxide and calcium salt 0-10wt%, sodium tripolyphosphate or sodium trimetaphosphate 0-20%, calcium polyphosphate 0-20%, sodium chloride 0.9%, chlorhexidine and fucoidan polyphenol 0-0.002wt%.
3. A method of preparing a pre-mixed injectable primary root canal filling material as claimed in claim 1, wherein, In step S1, the X-ray blocking component is any one of iodoform and barium sulfate.
4. A method of preparing a pre-mixed injectable primary root canal filling material as claimed in claim 1, wherein, In step S1, the calcium oxide is calcined calcium oxide, the calcium salt is calcium hydrogen phosphate, and the polyphosphate is trisodium polyphosphate or trisodium metaphosphate, and calcium polyphosphate.
5. A method of preparing a pre-mixed injectable primary root canal filling material as claimed in claim 1, wherein, In step S1, the antibacterial agent and biological polyphenol are chlorhexidine or fucoidan polyphenol, and the mass ratio of chlorhexidine to fucoidan polyphenol is 0 to 1:
3.
6. A method of preparing a pre-mixed injectable primary root canal filling material as claimed in claim 1, wherein, In step S2, the water-soluble non-aqueous liquid is glycerol or polyethylene glycol-400 / 600.
7. A method of preparing a pre-mixed injectable primary root canal filling material as claimed in claim 1, wherein, In step S2, the liquid-powder ratio of water-soluble non-aqueous liquid to solid powder mixture is 0.5mL / g.
8. A method of preparing a pre-mixed injectable primary root canal filling material as claimed in claim 1, wherein, In step S2, the rotation speed of ball milling is 200r / min, and the ball milling time is 24h.
9. A premixed injectable primary tooth root canal filling material prepared by the method of any one of claims 1-8.
10. Use of the premixed injectable primary tooth root canal filling material of claim 9 in the preparation of a primary tooth root canal treatment material.