Oral composition as well as application and use method thereof

Abstract

The invention relates to the field of oral care, and discloses an oral composition as well as application and a use method thereof. The oral composition contains chondroitin sulfate, calcium salt and phosphorus salt, on the basis of the total mass of the oral composition, the content of the chondroitin sulfate is 0.05-2%, the content of the calcium salt is 0.1-0.3%, and the content of the phosphorus salt is 0.1-0.3%. The oral composition can significantly improve the quality of generated hydroxyapatite crystals, realizes deep and lasting sealing, enhances the acid erosion resistance, improves the remineralization efficiency, and has a significant market prospect.

Description

Technical Field

[0001] This invention relates to the field of oral care, specifically to an oral composition and its application and method of use. Background Technology

[0002] Dentin hypersensitivity, tooth erosion, and early caries (demineralization) are common oral health problems with a high incidence and wide population impact, seriously affecting patients' oral comfort, chewing function, and even overall quality of life. The core pathological mechanisms of these oral problems are closely related to the mineralization imbalance of the hard tissues of the teeth. Specifically, demineralization damage occurs in the dentin, or dentinal tubules are exposed due to enamel wear, caries, etc., making it easier for external stimuli to be transmitted to the dental pulp nerve, causing sensitivity and discomfort. If early caries is not intervened in time, the demineralization area will continue to expand, further damaging the tooth structure and eventually leading to cavity formation, increasing the difficulty of treatment and patient suffering.

[0003] The key technological direction for solving the aforementioned oral problems lies in achieving dentin remineralization, which involves redepositing hydroxyapatite (HAP) crystals in demineralized areas or exposed dentinal tubules using specific methods. This repairs the damaged mineralized structure, seals the dentinal tubules, and thus restores the mechanical properties and barrier function of dentin. Therefore, developing efficient and high-quality dentin remineralization technologies and related compositions has become a research hotspot and important need in the fields of oral medicine and biomaterials.

[0004] Currently, dentin remineralization techniques mainly focus on intervention using fluoride and inorganic calcium-phosphorus solutions. However, existing fluoride-based remineralization techniques have significant drawbacks: on the one hand, the remineralization efficiency is low, making it difficult to quickly and effectively repair moderate to severe demineralization damage; on the other hand, the mineralized layer induced by fluoride is mostly limited to the dentin surface and cannot penetrate deep into the dentinal tubules, failing to form a dense and continuous repair layer. This results in poor durability and stability of the remineralization effect, making it difficult to fundamentally solve the problems of dentin hypersensitivity and recurrence of early caries. Summary of the Invention

[0005] The purpose of this invention is to overcome the problems existing in the prior art and provide an oral composition, its application, and a method of use. This oral composition can significantly improve the quality of the generated hydroxyapatite crystals, achieve deep and lasting sealing, enhance resistance to acid erosion, and improve remineralization efficiency.

[0006] To achieve the above objectives, the first aspect of the present invention provides an oral composition containing chondroitin sulfate, calcium salt, and phosphate salt; based on the total mass of the oral composition, the content of chondroitin sulfate is 0.05-2%, the content of calcium salt is 0.1-0.3%, and the content of phosphate salt is 0.1-0.3%.

[0007] Preferably, the chondroitin sulfate is chondroitin sulfate-C, and more preferably chondroitin sulfate-C with a 6-O-sulfation degree higher than 90%.

[0008] Preferably, the molecular weight of the chondroitin sulfate is 10-30 kDa.

[0009] Preferably, the molar ratio of calcium to phosphorus in the oral composition is 1.3-1.8, more preferably 1.55-1.75.

[0010] Preferably, the calcium salt is selected from at least one of calcium chloride, calcium nitrate, and calcium lactate.

[0011] Preferably, the phosphate salt is selected from at least one of disodium hydrogen phosphate, potassium dihydrogen phosphate, and glycerophosphate.

[0012] Preferably, the oral composition further contains a buffer solution such that the pH of the oral composition is 6.5-7.2.

[0013] Preferably, the buffer solution is a phosphate buffer and / or a hydroxyethylpiperazine ethanesulfonic acid buffer.

[0014] Preferably, the oral composition further contains excipients.

[0015] Preferably, the excipients are selected from at least one of thickeners, humectants, flavoring agents, and synergists.

[0016] Preferably, the thickener is carbomer and / or sodium carboxymethyl cellulose, the humectant is glycerin, and the synergist is xylitol and / or sodium fluoride.

[0017] The second aspect of the present invention provides the use of the oral composition provided in the first aspect above in the preparation of products that improve dentin remineralization.

[0018] The third aspect of the present invention provides the use of the oral composition provided in the first aspect above in the preparation of products for preventing or relieving tooth sensitivity.

[0019] A fourth aspect of the present invention provides a method of using an oral composition, characterized in that demineralized dentin or exposed dentinal tubules are brought into contact with the oral composition provided in the first aspect.

[0020] Preferably, the contact method is coating, impregnation, or spraying.

[0021] Preferably, the contact conditions include at least the following: a temperature of 35-40°C and a time of 5-20 minutes.

[0022] The beneficial effects of the present invention through the above technical solution are as follows: The oral composition provided by this invention, through the combined action of specific amounts of chondroitin sulfate, calcium salt and phosphate salt, can significantly improve the quality of the generated hydroxyapatite crystals, achieve deep and lasting sealing, enhance resistance to acid erosion, and improve remineralization efficiency, and has significant market prospects. Detailed Implementation

[0023] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0024] The first aspect of the present invention provides an oral composition comprising chondroitin sulfate, calcium salt and phosphate salt; based on the total mass of the oral composition, the content of chondroitin sulfate is 0.05-2%, the content of calcium salt is 0.1-0.3%, and the content of phosphate salt is 0.1-0.3%.

[0025] In this invention, based on the total mass of the oral composition, the content of chondroitin sulfate can be 0.05%, 0.1%, 0.15%, 0.2%, or any value between the two aforementioned values; the content of calcium salt can be 0.1%, 0.2%, 0.3%, or any value between the two aforementioned values; and the content of phosphate salt can be 0.1%, 0.2%, 0.3%, or any value between the two aforementioned values.

[0026] During their research, the inventors of this invention unexpectedly discovered that the oral composition, through the combined action of specific amounts of chondroitin sulfate, calcium salt, and phosphate salt, can significantly improve the quality of the generated hydroxyapatite crystals, achieve deep and lasting sealing, enhance resistance to acid erosion, and improve remineralization efficiency, thus showing significant market potential.

[0027] According to the present invention, chondroitin sulfate can be chondroitin sulfate-C (CS-C), chondroitin sulfate-A (CS-A), chondroitin sulfate-D (CS-D), etc. Preferably, the chondroitin sulfate is chondroitin sulfate-C, and more preferably chondroitin sulfate-C with a 6-O-sulfation degree higher than 90%. The inventors have found that, under this preferred embodiment, chondroitin sulfate, as a core component of the extracellular matrix (ECM), can naturally participate in the mineralization process of bones and teeth, and improve the remineralization efficiency of bones and teeth.

[0028] According to the present invention, preferably, the molecular weight of the chondroitin sulfate is 10-30 kDa, and can be 10 kDa, 20 kDa, 30 kDa, or any value between the two aforementioned values. It should be noted that the molecular weight refers to the weight-average molecular weight of the chondroitin sulfate. The inventors have found that, under this preferred embodiment, the permeability and bioactivity of chondroitin sulfate can be improved, thereby improving the quality of the hydroxyapatite crystals formed in the oral composition, enhancing the resistance to acid erosion, and improving remineralization efficiency.

[0029] According to the present invention, preferably, the molar ratio of calcium to phosphorus in the oral composition is 1.3-1.8, which can be 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, or any value between the two aforementioned values; more preferably, the molar ratio of calcium to phosphorus in the oral composition is 1.55-1.75. The inventors have found that, under this preferred embodiment, the synergistic effect of calcium and phosphorus in a specific molar ratio can further improve the quality of the generated hydroxyapatite crystals, enhance acid resistance, and improve remineralization efficiency.

[0030] According to the present invention, the calcium salt is a soluble calcium salt. In order to further improve the quality of the generated hydroxyapatite crystals, the acid erosion resistance and the remineralization efficiency, preferably, the calcium salt is selected from at least one of calcium chloride, calcium nitrate and calcium lactate.

[0031] According to the present invention, the phosphate salt can be an organic phosphate or an inorganic phosphate, and the phosphate salt is a soluble phosphate salt. In order to further improve the quality of the generated hydroxyapatite crystals, the acid erosion resistance and the remineralization efficiency, the phosphate salt is preferably selected from at least one of disodium hydrogen phosphate, potassium dihydrogen phosphate and glycerophosphate.

[0032] According to the present invention, in order to further improve the quality, acid resistance and remineralization efficiency of the generated hydroxyapatite crystals, preferably, the oral composition further contains a buffer solution such that the pH of the oral composition is 6.5-7.2, which can be 6.5, 6.7, 6.9, 7.2, or any value between the two aforementioned values.

[0033] According to the present invention, preferably, the buffer solution is a phosphate buffer and / or a hydroxyethylpiperazine ethanesulfonic acid buffer (HEPES); more preferably, the buffer solution is / or a hydroxyethylpiperazine ethanesulfonic acid buffer. The inventors have found that, in this preferred embodiment, the buffer solution is a phosphate buffer and / or a hydroxyethylpiperazine ethanesulfonic acid buffer (HEPES), and is convenient to use.

[0034] According to the present invention, in order to further improve the quality of the generated hydroxyapatite crystals, their resistance to acid erosion, and their remineralization efficiency, the oral composition preferably further contains excipients.

[0035] According to the present invention, in order to further improve the quality, acid resistance and remineralization efficiency of the generated hydroxyapatite crystals, preferably, the excipients are selected from at least one of thickeners, humectants, flavoring agents and synergists.

[0036] According to the present invention, the thickener may be carbomer, sodium carboxymethyl cellulose, xanthan gum, gum arabic, carrageenan, starch, etc.; the humectant may be glycerin, polyethylene glycol, ethylene glycol, propylene glycol, etc.; and the synergistic agent may be xylitol, sorbitol, sodium fluoride, etc. To further improve the quality, acid resistance, and remineralization efficiency of the generated hydroxyapatite crystals, preferably, the thickener is carbomer and / or sodium carboxymethyl cellulose, the humectant is glycerin, and the synergistic agent is xylitol and / or sodium fluoride.

[0037] In this invention, the flavoring agent can be a conventionally selected flavoring agent in the art, such as a sweetener, acidulant, or flavoring, and can be adjusted according to actual needs.

[0038] According to a particularly preferred embodiment of the present invention, an oral composition is provided, comprising chondroitin sulfate, calcium salt, phosphate salt, hydroxyethylpiperazine ethanesulfonic acid buffer, and excipients; based on the total mass of the oral composition, the content of chondroitin sulfate is 0.05-2%, the content of calcium salt is 0.1-0.3%, and the content of phosphate salt is 0.1-0.3%. The molar ratio of calcium to phosphorus in the oral composition is 1.62-1.72; the chondroitin sulfate is chondroitin sulfate-C with a 6-O-sulfation degree higher than 90% and a molecular weight of 10-30 kDa; the calcium salt is selected from at least one of calcium chloride, calcium nitrate and calcium lactate; the phosphate salt is selected from at least one of disodium hydrogen phosphate, potassium dihydrogen phosphate and glycerophosphate; the excipients are selected from at least one of thickener, humectant, flavoring agent and synergist; the thickener is carbomer and / or sodium carboxymethyl cellulose, the humectant is glycerin, and the synergist is xylitol and / or sodium fluoride.

[0039] The oral composition obtained through the above-mentioned preferred embodiments, through the combined effect of specific amounts of chondroitin sulfate, calcium salt and phosphate salt, can significantly improve the quality of the generated hydroxyapatite crystals, achieve deep and lasting sealing, enhance resistance to acid erosion, and improve remineralization efficiency.

[0040] In this invention, any conventionally selected method in the art can be used to prepare the oral composition. Preferably, a method for preparing the oral composition is provided, which includes mixing the raw materials of the oral composition.

[0041] A second aspect of the present invention provides the use of the oral composition described in the first aspect in the preparation of products that improve dentin remineralization.

[0042] Dentin is the main hard tissue that makes up a tooth. It lies within the enamel and cementum, and forms the lateral walls of the pulp chamber and root canals. It is pale yellow in color and contains approximately 30% organic matter and water, and 70% inorganic matter. Its hardness is lower than that of enamel. Under a microscope, many regularly arranged fine tubules called dentinal tubules can be seen within the dentin. These tubules contain nerve fibers. When dentin is exposed, it can sense external stimuli such as cold, heat, acid, and sweetness, causing pain. Therefore, sealing the dentinal tubules can isolate external stimuli such as cold, heat, acid, and sweetness, preventing or alleviating tooth sensitivity.

[0043] A third aspect of the present invention provides the use of the oral composition described in the first aspect above in the preparation of products for preventing or relieving tooth sensitivity.

[0044] A fourth aspect of the present invention provides a method of using an oral composition, characterized in that demineralized dentin or exposed dentinal tubules are brought into contact with the oral composition described in the first aspect.

[0045] According to the present invention, preferably, the contact is made by coating, impregnation or spraying.

[0046] According to the present invention, preferably, the contact conditions include at least: a temperature of 35-40°C, which can be 35°C, 36°C, 37°C, 38°C, 39°C, 40°C, or any value between the two aforementioned values; and a time of 5-20 min, which can be 5 min, 10 min, 15 min, 20 min, or any value between the two aforementioned values.

[0047] The present invention will be described in detail below through embodiments.

[0048] Unless otherwise specified, the experimental methods and equipment described in the following examples are conventional methods and equipment.

[0049] Unless otherwise specified, the raw materials in the following examples are all commercially available.

[0050] Example 1 First, 0.5 g of chondroitin sulfate-C (CS-C) with a molecular weight of approximately 25 kDa was weighed and dissolved in 80 mL of purified water. Then, 0.22 g of calcium chloride (CaCl2) and 0.18 g of disodium hydrogen phosphate (Na2HPO4) were added. The pH of the mixture was precisely controlled at 6.8 ± 0.1 using HEPES buffer to ensure the stability of CS-C and that the calcium and phosphorus ions were in a moderately metastable state. Finally, an appropriate amount of thickener (such as sodium carboxymethyl cellulose) was added to adjust the viscosity of the composition, and the volume was brought up to 100 mL with purified water to obtain the final remineralized composition A1. In this composition, the calcium-to-phosphorus molar ratio (Ca / P) is approximately 1.56, and the concentration of CS-C is 0.5% (w / v).

[0051] Example 2 First, 2 grams of chondroitin sulfate-C (CS-C) with a molecular weight of approximately 25 kDa were weighed and dissolved in 80 mL of purified water. Then, 0.16 g of calcium chloride (CaCl2) and 0.12 g of disodium hydrogen phosphate (Na2HPO4) were added. The pH of the mixture was precisely controlled at 6.8 ± 0.1 using HEPES buffer to ensure the stability of CS-C and that the calcium and phosphorus ions were in a moderately metastable state. Finally, an appropriate amount of thickener (such as sodium carboxymethyl cellulose) was added to adjust the viscosity of the composition, and the volume was brought up to 100 mL with purified water to obtain the final remineralized composition A1. In this composition, the calcium-to-phosphorus molar ratio (Ca / P) is approximately 1.70, and the concentration of CS-C is 2% (w / v).

[0052] Example 3 First, weigh 1 gram of chondroitin sulfate-C (CS-C) with a molecular weight of approximately 25 kDa and dissolve it in 80 mL of purified water. Then, add 0.28 g of calcium chloride (CaCl2) and 0.22 g of disodium hydrogen phosphate (Na2HPO4). The pH of the mixture is precisely controlled at 6.8 ± 0.1 using HEPES buffer to ensure the stability of CS-C and that the calcium and phosphorus ions are in a moderately metastable state. Finally, add an appropriate amount of thickener (such as sodium carboxymethyl cellulose) to adjust the viscosity of the composition, and bring the volume to 100 mL with purified water to obtain the final remineralized composition A1. In this composition, the calcium-to-phosphorus molar ratio (Ca / P) is approximately 1.62, and the concentration of CS-C is 1% (w / v).

[0053] Example 4 The remineralized composition was prepared according to the method of Example 1, except that chondroitin sulfate-C was replaced with an equal mass and molecular weight of chondroitin sulfate-A (CS-A, 4-O-sulfated).

[0054] Example 5 The remineralized composition was prepared according to the method of Example 1, except that chondroitin sulfate-C was replaced with chondroitin sulfate-C with a molecular weight of 5 kDa.

[0055] Example 6 The remineralization composition was prepared according to the method of Example 1, except that the amount of calcium chloride was replaced with 0.18 g and the amount of disodium hydrogen phosphate was replaced with 0.17 g, and the calcium-to-phosphorus molar ratio in the composition was approximately 1.35.

[0056] Example 7 The remineralization composition was prepared according to the method of Example 1, except that the amount of calcium chloride was replaced with 0.3 g, and the calcium-to-phosphorus molar ratio in the composition was approximately 3.2.

[0057] Comparative Example 1 HEPES buffer at pH 6.8.

[0058] Comparative Example 2 The remineralized composition was prepared according to the method of Example 1, except that chondroitin sulfate-C was not added.

[0059] Comparative Example 3 The remineralization composition was prepared according to the method of Example 1, except that the amount of chondroitin sulfate-C was replaced with 5%, the amount of calcium chloride was replaced with 0.44 g, and the amount of disodium hydrogen phosphate was replaced with 0.36 g.

[0060] Test Example 1 Bovine dentin slices treated with 0.1M citric acid solution for 10 minutes were used as experimental models. The demineralized dentin slices were immersed in the remineralization compositions prepared in Examples 1-7 and Comparative Examples 1-3, respectively, for 15 minutes each time, 3 times a day for 14 days. The SEM images, remineralization depth, decrease in liquid permeability and HAP crystallization (XRD) of the dentin slices were tested. The results are shown in Table 1.

[0061] (1) Liquid permeability (Lp) test method The sealing effect of dentinal tubules was determined using a modified hydrodynamic apparatus (Pashley fluid conduction model).

[0062] Sample preparation: Dentin slices were fixed in a liquid permeability testing device and connected to a deionized water hydrostatic system with a pressure of 20 cm H2O (or adjusted according to the actual experimental pressure).

[0063] Test steps: a. Determine the baseline value (Lp1): Record the fluid permeation rate of the dentin sheet after acid etching and demineralization per unit time, and calculate the initial liquid permeability.

[0064] b. Processing and Measurement (Lp2): After remineralizing the dentin sheet (as described in the examples), it was reinstalled into the device, and the liquid permeability after processing was measured under the same pressure conditions.

[0065] The rate of decrease in liquid permeability (%) is calculated using the following formula: Liquid permeability decrease rate (%) = [(Lp1-Lp2) / Lp1] ×100%; The higher the value, the better the sealing effect on the dentinal tubules.

[0066] (2) Analysis of remineralization depth and microstructure (SEM / EDS) Sample preparation: The treated dentin sections were longitudinally split along the long axis of the tooth to expose the longitudinal section of the dentinal tubules. The samples were then subjected to gradient ethanol dehydration, critical point drying, and gold sputtering.

[0067] SEM observation and depth measurement: The longitudinal section was observed using a scanning electron microscope (SEM) at an accelerating voltage of 10-15kV. The dentinal tubules were located and traced deeper. The maximum distance that the deposits (mineralized plugs) in the lumen extended from the surface to the depth was measured, which is the remineralization depth.

[0068] EDS elemental analysis: X-ray energy dispersive spectroscopy (EDS) was performed on the sediment area to determine the elemental content of calcium (Ca) and phosphorus (P), and the Ca / P molar ratio was calculated to confirm whether the sediment was hydroxyapatite (e.g., in the oral composition prepared in Example 1, the theoretical Ca / P molar ratio is about 1.56).

[0069] (3) HAP crystallinity test (XRD) X-ray diffraction (XRD) was used to analyze the phase composition of deposits on the surface of dentin slices. The radiation source was Cu-Kα rays (λ=0.15406nm), the tube voltage was 40kV, and the tube current was 40mA. The scanning range (2θ) was 20° to 60°, the step size was 0.02°, and the scanning speed was 2° / min.

[0070] Based on the full width at half maximum (FWHM) of the characteristic diffraction peaks in the spectrum, the grain size is calculated using the Scherrer equation, and the crystallinity is then assessed accordingly. D=Kλ / (β cosθ) Where D is the average thickness of the grain perpendicular to the crystal plane, K is the Scherrer constant (taken as 0.89), λ is the X-ray wavelength, β is the full width at half maximum (FWHM) of the diffraction peak of the measured sample (in radians), and θ is the Bragg diffraction angle. Larger grain size indicates higher crystallinity.

[0071] Table 1

[0072] As shown in Table 1, the liquid permeability of the dentin sheet treated with the remineralization composition prepared in Example 1 decreased by approximately 95% compared to the demineralized state, indicating that the dentinal tubules were sealed most effectively. The liquid permeability of the dentin sheet treated with the remineralization composition prepared in Example 4 decreased by approximately 65% ​​compared to the demineralized state. The liquid permeability of the dentin sheet treated with the remineralization composition prepared in Comparative Example 2 decreased by only approximately 40% compared to the demineralized state. This demonstrates the significant advantage of CS-C in sealing dentinal tubules.

[0073] SEM structural observation (crystal quality and sealing): SEM images of dentin slices treated with the remineralization composition prepared in Example 1 showed that the dentinal tubule orifices were completely covered and sealed by a dense layer of regularly arranged plate-like HAP crystals. In contrast, only a small number of irregular spherical particles were observed as deposits on the surface of dentin slices treated with the remineralization composition prepared in Comparative Example 2, indicating incomplete sealing of the tubule orifices. The morphology and density of the precipitate in dentin slices treated with the remineralization composition prepared in Example 4 were between those of the Example 1 group and the Comparative Example 2 group, demonstrating that the 6-O-sulfation sites are crucial for directional guidance.

[0074] Remineralization depth analysis (CLSM or EDS): The dentin sheets treated with the remineralization composition prepared in Example 1 achieved a mineralization plug depth of 25-35 μm within the dentinal tubules. In contrast, the dentin sheets treated with the remineralization composition prepared in Comparative Example 2 only achieved a mineralization depth of 10-15 μm. This strongly demonstrates that CS-C molecules can effectively penetrate and guide deep remineralization, overcoming the deficiency of insufficient sealing depth in existing technologies.

[0075] Test Example 2 The dentin samples from Example 1 and Comparative Example 2, after undergoing 14 days of remineralization treatment, were immersed again in an acid solution with pH=4.0 for 1 hour for hardness testing. The results are shown in Table 2.

[0076] The hardness testing process includes testing the samples using a Vickers Microhardness Tester. The testing is based on the general principles of micro-force hardness testing in ISO 6507-1 standard, and adjusted according to specific parameters from oral dentin research.

[0077] (1) Initial hardness determination (VHN) pre ) The dentin slices (example group and comparative group) that had undergone 14 days of remineralization were rinsed with deionized water and dried.

[0078] Fix the sample on the stage of the microhardness tester, keeping the test surface horizontal.

[0079] A diamond pyramid indenter is used to apply a load of 25-50g (0.245-0.49 N) for a holding time of 10-15 seconds.

[0080] Five test points (with a spacing of more than 50 μm between each point) were randomly selected in the remineralized area of ​​each sample. The diagonal length of the indentation was measured, and the Vickers hardness value (VHN) was automatically calculated. The average value was recorded as the initial hardness of the remineralized layer.

[0081] (2) Acid Challenge Experiment Prepare an acetic acid buffer solution with pH=4.0 as the acid etching solution.

[0082] The sample with the initial hardness measured was completely immersed in the above acid solution and treated at a constant temperature of 37°C for 1 hour.

[0083] Remove the sample, rinse thoroughly with deionized water to terminate the acid etching reaction, and dry it for testing.

[0084] (3) Hardness determination after acid etching (VHN) post ) and thickness loss measurement Hardness test: Using the same parameters as in step (1), the surface of the sample after acid challenge is tested for hardness and recorded as hardness after acid challenge.

[0085] Thickness loss measurement: The sample is longitudinally cut open and the cross-section is observed by scanning electron microscopy (SEM) to measure the thickness change of the remineralized layer before and after acid etching; or the height of the acid etching step is measured using a micrometer / profilometer.

[0086] (4) Data calculation method Based on the measured data, the surface hardness reduction rate and the remineralized layer thickness loss rate are calculated using the following formulas: Surface hardness reduction rate (%) = (VHN) pre VHN post ) / VHN pre ×100%; Remineralization layer thickness loss rate (%) = (initial thickness) (thickness after acid etching) / initial thickness × 100%.

[0087] Table 2

[0088] As shown in Table 2, the dentin slices from Example 1, after remineralization treatment, exhibited significantly less loss in remineralized layer thickness and hardness compared to Comparative Example 2 after immersion in acid. This indicates that the high-quality, highly crystalline HAP crystals formed under CS-C guidance endow the restoration layer with stronger resistance to acid erosion.

[0089] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combining the various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. An oral composition, characterized in that, The oral composition contains chondroitin sulfate, calcium salt, and phosphate salt; based on the total mass of the oral composition, the content of chondroitin sulfate is 0.05-2%, the content of calcium salt is 0.1-0.3%, and the content of phosphate salt is 0.1-0.3%.

2. The oral composition according to claim 1, characterized in that, The chondroitin sulfate is chondroitin sulfate-C, preferably chondroitin sulfate-C with a 6-O-sulfation degree higher than 90%; Preferably, the molecular weight of the chondroitin sulfate is 10-30 kDa.

3. The oral composition according to claim 1, characterized in that, The molar ratio of calcium to phosphorus in the oral composition is 1.3-1.8, preferably 1.55-1.

75.

4. The oral composition according to any one of claims 1 to 3, characterized in that, The calcium salt is selected from at least one of calcium chloride, calcium nitrate and calcium lactate; Preferably, the phosphate salt is selected from at least one of disodium hydrogen phosphate, potassium dihydrogen phosphate, and glycerophosphate.

5. The oral composition according to any one of claims 1 to 3, characterized in that, The oral composition also contains a buffer solution, such that the pH of the oral composition is 6.5-7.2; Preferably, the buffer solution is a phosphate buffer and / or a hydroxyethylpiperazine ethanesulfonic acid buffer.

6. The oral composition according to any one of claims 1 to 3, characterized in that, The oral composition also contains excipients; Preferably, the excipients are selected from at least one of thickeners, humectants, flavoring agents, and synergists; Preferably, the thickener is carbomer and / or sodium carboxymethyl cellulose, the humectant is glycerin, and the synergist is xylitol and / or sodium fluoride.

7. The use of the oral composition according to any one of claims 1 to 6 in the preparation of products that improve dentin remineralization.

8. The use of the oral composition according to any one of claims 1 to 6 in the preparation of products for preventing or relieving tooth sensitivity.

9. A method of using an oral composition, characterized in that, Contact the demineralized dentin or exposed dentinal tubules with the oral composition according to any one of claims 1 to 6.

10. The method of use according to claim 9, characterized in that, The contact method is coating, dipping, or spraying; Preferably, the contact conditions include at least the following: a temperature of 35-40°C and a time of 5-20 minutes.

Images