A dental implant with a high-bioactivity surface coating and a method for preparing the same

Abstract

The application relates to the field of implant technology, and particularly relates to a dental implant with a high-bioactivity surface coating and a preparation method thereof; in order to improve the bioactivity of a dental implant and improve the healing condition of the dental implant after implantation, the dental implant surface is first subjected to sand blasting treatment for roughening and acid liquid and alkali liquid immersion treatment, the content of hydroxyl groups on the surface of the dental implant is increased, the hydrophilicity of the dental implant is improved, the content of active groups on the surface of the dental implant is increased, and on this basis, a polydopamine coating containing exosome microcapsules is introduced into the surface of the dental implant, so that the antibacterial performance of the dental implant is improved and the proliferation of cells is induced, the implantation of the dental implant is accelerated, and the bioaffinity of the dental implant is greatly improved.

Description

Technical Field

[0001] This invention relates to the field of implant technology, specifically to a dental implant with a highly bioactive surface coating and its preparation method. Background Technology

[0002] In the field of oral medicine, dental implant technology has increasingly become a routine method for restoring missing teeth, significantly improving treatment outcomes and patients' quality of life. Currently, titanium alloy is the mainstream material for making implants, but it differs fundamentally from natural teeth in its tissue structure. Especially during the actual implantation process, titanium alloy surfaces have low bioactivity, making it difficult to guide connective tissue attachment and osteoblast proliferation, resulting in a often longer postoperative healing period. In addition, the oral cavity has a complex microbiome, and implants are susceptible to bacterial colonization and biofilm formation in the early stages of implantation, which further increases the difficulty of achieving long-term implant stability. Summary of the Invention

[0003] The purpose of this invention is to provide a dental implant with a highly bioactive surface coating and a method for preparing the same, in order to solve the problems raised in the prior art.

[0004] To achieve the above objectives, the present invention provides the following technical solution: a dental implant with a highly bioactive surface coating, having the following technical features: the dental implant with a highly bioactive surface coating is composed of a titanium alloy dental implant matrix and an active polydopamine coating loaded on its surface;

[0005] The polydopamine coating contains exosome microcapsules.

[0006] Furthermore, the method for preparing the exosome microcapsules includes the following steps:

[0007] a. Dissolve sodium alginate in deionized water and stir until completely dissolved. Then, add sodium hydroxide dropwise to adjust the pH to 8.5-9.5. Under a nitrogen atmosphere, add EDC·HCl and N-hydroxysuccinimide. Stir and mix at room temperature for 30-45 minutes. Then, slowly add dimethylaminopropylamine. After the addition is complete, stir and react at room temperature for 18-24 hours. During the reaction, control the pH of the reaction system to 6.5-7. After the reaction is complete, dialyze the reaction solution. After dialysis, freeze-dry to obtain tertiary amine modified sodium alginate.

[0008] b. Disperse the tertiary amine-modified sodium alginate in deionized water, adjust the pH to 7.5-8, add 3-chloro-2-hydroxypropyltrimethylammonium chloride, stir and react for 18-24 hours. During the reaction, control the pH to 7.5-8. After the reaction is complete, precipitate the product with acetone, collect the precipitate, freeze dry it to obtain quaternized sodium alginate.

[0009] c. Disperse the exosomes in PBS buffer, mix well, add quaternized sodium alginate and sodium alginate, stir and mix well, and cool to 2~4℃ to obtain the exosome solution;

[0010] Add 0.3-0.5% by volume of Tween-80 to liquid paraffin, stir and mix thoroughly, then add exosome solution dropwise. During the dropwise addition, stir continuously to form an emulsion, then slowly add glutaraldehyde. After the dropwise addition is complete, stir and react at room temperature for 2-4 hours, then centrifuge to separate the precipitate, wash the precipitate 2-3 times with petroleum ether, and freeze-dry to obtain exosome microcapsules.

[0011] Furthermore, in step a, the amounts of each component added, by weight, are 10 parts sodium alginate, 5-8 parts EDC・HCl, 3-5 parts N-hydroxysuccinimide, and 0.5-5 parts dimethylaminopropylamine.

[0012] Furthermore, in step a, the dialysis bag used during dialysis is 5~10kDa.

[0013] Furthermore, in step b, the amount of each component added, by weight, is 10 parts of tertiary amine-modified sodium alginate and 1-5 parts of 3-chloro-2-hydroxypropyltrimethylammonium chloride.

[0014] Furthermore, in step c, the amount of each component added, by weight, is 0.5-1 part exosomes, 2-10 parts quaternized sodium alginate, 15-30 parts sodium alginate, and 1.5-5 parts glutaraldehyde.

[0015] Furthermore, a method for preparing a dental implant with a highly bioactive surface coating includes the following steps:

[0016] S1. Preparation of titanium alloy dental implant matrix;

[0017] After the surface of the titanium alloy rod is machined into the required shape, it is cleaned and dried with deionized water and anhydrous ethanol in sequence. Then, the surface is roughened by sandblasting. After that, it is immersed in acid and alkali solutions to activate the surface. After cleaning and drying with deionized water and anhydrous ethanol again, the titanium alloy dental implant matrix is ​​obtained.

[0018] S2. Preparation of an active polydopamine coating;

[0019] Dopamine hydrochloride was dissolved in deionized water and stirred until completely dissolved. Exosome microcapsules were then added and stirred until evenly dispersed. Ammonia was added dropwise to adjust the pH of the mixture to 8.5-9. The titanium alloy dental implant substrate was then completely immersed in the mixture. The mixture was heated to 30-37°C and stirred for 6-12 hours. The titanium alloy dental implant substrate was then removed and its surface was washed with ultrapure water 2-3 times. After freeze-drying, an active polydopamine coating was formed on its surface, resulting in a dental implant with a highly bioactive surface coating.

[0020] Furthermore, in step S1, the acid solution is a mixed solution of sulfuric acid solution and hydrochloric acid solution in a volume ratio of 1:1;

[0021] The sulfuric acid solution has a concentration of 45-55 wt%; the hydrochloric acid solution has a concentration of 5-20 wt%.

[0022] Furthermore, in step S1, the alkaline solution is a sodium hydroxide solution with a concentration of 10~20wt%.

[0023] Furthermore, the mass ratio of dopamine hydrochloride to exosome microcapsules is 100:(1~5).

[0024] Compared with the prior art, the beneficial effects of the present invention are:

[0025] In order to improve the bioactivity of dental implants and improve their healing after implantation, this invention modifies the surface of dental implants. First, the surface of the dental implant is roughened by sandblasting, and then soaked in acid and alkali solutions to increase the hydroxyl content of the surface, improve its hydrophilicity, and increase the content of active groups on the surface.

[0026] Furthermore, based on this, the present invention introduces a polydopamine coating containing exosome microcapsules onto the surface of the dental implant; the present invention uses sodium alginate as a raw material, and under the action of condensing agent EDC・HCl and N-hydroxysuccinimide, the carboxylic acid group in sodium alginate undergoes an amidation reaction with the amino group in dimethylaminopropylamine, thereby introducing a tertiary amine group into sodium alginate. Then, it is mixed with 3-chloro-2-hydroxypropyltrimethylammonium chloride, and the nitrogen atom in the tertiary amine group attacks the carbon atom in 3-chloro-2-hydroxypropyltrimethylammonium chloride that is attached to chlorine, thereby undergoing a nucleophilic substitution reaction, and thus realizing the quaternization of the tertiary amine group, to prepare sodium alginate with quaternary ammonium functional groups;

[0027] The quaternary ammonium salt functional groups contained therein can exert a strong antibacterial effect against Gram-negative anaerobic bacteria, such as Porphyromonas gingivalis, thereby avoiding bacterial invasion after dental implantation and reducing post-implantation inflammatory response. Furthermore, in the preparation of exosome microcapsules, the cross-linking agent used in this invention is glutaraldehyde. After cross-linking, some unreacted aldehyde groups will still exist on the surface of the microcapsule wall material. These aldehyde groups will react with the amino groups in dopamine hydrochloride when the microcapsule comes into contact with dopamine hydrochloride, thereby introducing catechol groups on the surface of the microcapsule. These catechol groups can then participate in the polymerization reaction of dopamine in an alkaline environment, thereby increasing the bonding strength between the microcapsule and the polydopamine coating, thus reducing the detachment of the microcapsule after implantation.

[0028] Furthermore, the core material used in this invention is exosomes, a type of nanoscale capsule secreted by cells, containing a large number of active factors that can inhibit the expression of pro-inflammatory factors and induce cell proliferation, thereby accelerating the implantation of dental implants and significantly improving the biocompatibility of dental implants. In order to avoid the deactivation of exosomes, this invention first mixes exosomes with sodium alginate and forms an emulsion in liquid paraffin when preparing microcapsules, so that the exosomes are partially coated by sodium alginate in advance. Therefore, during the subsequent glutaraldehyde crosslinking, the activity of exosomes can be preserved and the deactivation of exosomes can be avoided. In addition, this invention also uses a freeze-drying process to avoid the deactivation defects of exosomes caused by traditional microcapsule drying processes. Detailed Implementation

[0029] Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0030] The exosomes used in this invention are FRE-08 type human umbilical cord mesenchymal stem cell exosomes.

[0031] Example 1. A method for preparing a dental implant with a highly bioactive surface coating, comprising the following steps:

[0032] S1. Preparation of titanium alloy dental implant matrix;

[0033] After the surface of the titanium alloy rod is machined into the required shape, it is cleaned and dried with deionized water and anhydrous ethanol in sequence. Then, the surface is roughened by sandblasting. After that, it is immersed in acid and alkali solutions to activate the surface. After cleaning and drying with deionized water and anhydrous ethanol again, the titanium alloy dental implant matrix is ​​obtained.

[0034] The acid solution is a mixed solution of sulfuric acid solution and hydrochloric acid solution in a volume ratio of 1:1;

[0035] The sulfuric acid solution has a concentration of 45 wt%; the hydrochloric acid solution has a concentration of 10 wt%.

[0036] The alkaline solution is a 10wt% sodium hydroxide solution;

[0037] S2. Preparation of an active polydopamine coating;

[0038] By weight, 100 parts of dopamine hydrochloride were dissolved in deionized water and stirred until completely dissolved. Then, 1 part of exosome microcapsules were added and stirred until evenly dispersed. Ammonia was added dropwise to adjust the pH of the mixture to 9. The titanium alloy dental implant matrix was then completely immersed in the mixture. The mixture was heated to 35°C and stirred for 8 hours. The titanium alloy dental implant matrix was then removed and its surface was washed three times with ultrapure water. After freeze-drying, an active polydopamine coating was formed on its surface, resulting in a dental implant with a highly bioactive surface coating.

[0039] The method for preparing the exosome microcapsules includes the following steps:

[0040] a. Dissolve 10 parts by weight of sodium alginate in deionized water and stir until completely dissolved. Then, add sodium hydroxide dropwise to adjust the pH to 9. Under a nitrogen atmosphere, add 5 parts of EDC·HCl and 3 parts of N-hydroxysuccinimide. Stir and mix at room temperature for 30 minutes. Then, slowly add 0.5 parts of dimethylaminopropylamine. After the addition is complete, stir and react at room temperature for 18 hours. During the reaction, control the pH of the reaction system to 6.5. After the reaction is complete, dialyze the reaction solution using a 10 kDa dialysis bag. After dialysis for 24 hours, the solution is lyophilized to obtain tertiary amine modified sodium alginate.

[0041] b. By weight, 10 parts of tertiary amine modified sodium alginate were dispersed in deionized water, the pH was adjusted to 7.5, 1 part of 3-chloro-2-hydroxypropyltrimethylammonium chloride was added, and the mixture was stirred for 18 hours. During the reaction, the pH was controlled at 7.5. After the reaction was completed, the product was precipitated with acetone, the precipitate was collected, and lyophilized to obtain quaternized sodium alginate.

[0042] c. By weight, disperse 0.5 parts of exosomes in PBS buffer, mix well, add 2 parts of quaternized sodium alginate and 30 parts of sodium alginate, stir and mix well, and cool to 2~4℃ to obtain exosome solution;

[0043] Add 0.5% by volume of Tween-80 to liquid paraffin, stir and mix thoroughly, then add exosome solution dropwise. During the dropwise addition, stir continuously to form an emulsion, then slowly add 1.5 parts of glutaraldehyde. After the dropwise addition is complete, stir and react at room temperature for 4 hours, then centrifuge to separate the precipitate, wash the precipitate three times with petroleum ether, and freeze-dry to obtain exosome microcapsules.

[0044] Example 2. A method for preparing a dental implant with a highly bioactive surface coating, comprising the following steps:

[0045] Compared with Example 1, this example increases the amount of exosome microcapsules added in step S2, while the other steps remain unchanged;

[0046] S1. Preparation of titanium alloy dental implant matrix;

[0047] After the surface of the titanium alloy rod is machined into the required shape, it is cleaned and dried with deionized water and anhydrous ethanol in sequence. Then, the surface is roughened by sandblasting. After that, it is immersed in acid and alkali solutions to activate the surface. After cleaning and drying with deionized water and anhydrous ethanol again, the titanium alloy dental implant matrix is ​​obtained.

[0048] The acid solution is a mixed solution of sulfuric acid solution and hydrochloric acid solution in a volume ratio of 1:1;

[0049] The sulfuric acid solution has a concentration of 45 wt%; the hydrochloric acid solution has a concentration of 10 wt%.

[0050] The alkaline solution is a 10wt% sodium hydroxide solution;

[0051] S2. Preparation of an active polydopamine coating;

[0052] By weight, 100 parts of dopamine hydrochloride were dissolved in deionized water and stirred until completely dissolved. Then, 5 parts of exosome microcapsules were added and stirred until evenly dispersed. Ammonia was added dropwise to adjust the pH of the mixture to 9. The titanium alloy dental implant substrate was then completely immersed in the mixture. The mixture was heated to 35°C and stirred for 8 hours. The titanium alloy dental implant substrate was then removed and its surface was washed three times with ultrapure water. After freeze-drying, an active polydopamine coating was formed on its surface, resulting in a dental implant with a highly bioactive surface coating.

[0053] Example 3. A method for preparing a dental implant with a highly bioactive surface coating, comprising the following steps:

[0054] Compared with Example 2, this example increases the amount of sodium quaternized alginate added in step c;

[0055] The method for preparing the exosome microcapsules includes the following steps:

[0056] a. Dissolve 10 parts by weight of sodium alginate in deionized water and stir until completely dissolved. Then, add sodium hydroxide dropwise to adjust the pH to 9. Under a nitrogen atmosphere, add 5 parts of EDC·HCl and 3 parts of N-hydroxysuccinimide. Stir and mix at room temperature for 30 minutes. Then, slowly add 0.5 parts of dimethylaminopropylamine. After the addition is complete, stir and react at room temperature for 18 hours. During the reaction, control the pH of the reaction system to 6.5. After the reaction is complete, dialyze the reaction solution using a 10 kDa dialysis bag. After dialysis for 24 hours, the solution is lyophilized to obtain tertiary amine modified sodium alginate.

[0057] b. By weight, 10 parts of tertiary amine modified sodium alginate were dispersed in deionized water, the pH was adjusted to 7.5, 1 part of 3-chloro-2-hydroxypropyltrimethylammonium chloride was added, and the mixture was stirred for 18 hours. During the reaction, the pH was controlled at 7.5. After the reaction was completed, the product was precipitated with acetone, the precipitate was collected, and lyophilized to obtain quaternized sodium alginate.

[0058] c. By weight, disperse 0.5 parts of exosomes in PBS buffer, mix well, add 10 parts of quaternized sodium alginate and 30 parts of sodium alginate, stir and mix well, and cool to 2~4℃ to obtain exosome solution;

[0059] Add 0.5% by volume of Tween-80 to liquid paraffin, stir and mix thoroughly, then add exosome solution dropwise. During the dropwise addition, stir continuously to form an emulsion, then slowly add 1.5 parts of glutaraldehyde. After the dropwise addition is complete, stir and react at room temperature for 4 hours, then centrifuge to separate the precipitate, wash the precipitate three times with petroleum ether, and freeze-dry to obtain exosome microcapsules.

[0060] Example 4. A method for preparing a dental implant with a highly bioactive surface coating, comprising the following steps:

[0061] Compared with Example 3, this example increases the amount of exosomes added in step c;

[0062] The method for preparing the exosome microcapsules includes the following steps:

[0063] a. Dissolve 10 parts by weight of sodium alginate in deionized water and stir until completely dissolved. Then, add sodium hydroxide dropwise to adjust the pH to 9. Under a nitrogen atmosphere, add 5 parts of EDC·HCl and 3 parts of N-hydroxysuccinimide. Stir and mix at room temperature for 30 minutes. Then, slowly add 0.5 parts of dimethylaminopropylamine. After the addition is complete, stir and react at room temperature for 18 hours. During the reaction, control the pH of the reaction system to 6.5. After the reaction is complete, dialyze the reaction solution using a 10 kDa dialysis bag. After dialysis for 24 hours, the solution is lyophilized to obtain tertiary amine modified sodium alginate.

[0064] b. By weight, 10 parts of tertiary amine modified sodium alginate were dispersed in deionized water, the pH was adjusted to 7.5, 1 part of 3-chloro-2-hydroxypropyltrimethylammonium chloride was added, and the mixture was stirred for 18 hours. During the reaction, the pH was controlled at 7.5. After the reaction was completed, the product was precipitated with acetone, the precipitate was collected, and lyophilized to obtain quaternized sodium alginate.

[0065] c. By weight, disperse 1 part of exosomes in PBS buffer, mix well, add 10 parts of quaternized sodium alginate and 30 parts of sodium alginate, stir and mix well, and cool to 2~4℃ to obtain exosome solution;

[0066] Add 0.5% by volume of Tween-80 to liquid paraffin, stir and mix thoroughly, then add exosome solution dropwise. During the dropwise addition, stir continuously to form an emulsion, then slowly add 1.5 parts of glutaraldehyde. After the dropwise addition is complete, stir and react at room temperature for 4 hours, then centrifuge to separate the precipitate, wash the precipitate three times with petroleum ether, and freeze-dry to obtain exosome microcapsules.

[0067] Example 5. A method for preparing a dental implant with a highly bioactive surface coating, comprising the following steps:

[0068] Compared with Example 4, this example increases the amount of dimethylaminopropylamine added in step a;

[0069] The method for preparing the exosome microcapsules includes the following steps:

[0070] a. Dissolve 10 parts by weight of sodium alginate in deionized water and stir until completely dissolved. Then, add sodium hydroxide dropwise to adjust the pH to 9. Under a nitrogen atmosphere, add 5 parts of EDC·HCl and 3 parts of N-hydroxysuccinimide. Stir and mix at room temperature for 30 minutes. Then, slowly add 5 parts of dimethylaminopropylamine. After the addition is complete, stir and react at room temperature for 18 hours. During the reaction, control the pH of the reaction system to 6.5. After the reaction is complete, dialyze the reaction solution using a 10 kDa dialysis bag. After dialysis for 24 hours, the solution is lyophilized to obtain tertiary amine modified sodium alginate.

[0071] b. By weight, 10 parts of tertiary amine modified sodium alginate were dispersed in deionized water, the pH was adjusted to 7.5, 1 part of 3-chloro-2-hydroxypropyltrimethylammonium chloride was added, and the mixture was stirred for 18 hours. During the reaction, the pH was controlled at 7.5. After the reaction was completed, the product was precipitated with acetone, the precipitate was collected, and lyophilized to obtain quaternized sodium alginate.

[0072] c. By weight, disperse 1 part of exosomes in PBS buffer, mix well, add 10 parts of quaternized sodium alginate and 30 parts of sodium alginate, stir and mix well, and cool to 2~4℃ to obtain exosome solution;

[0073] Add 0.5% by volume of Tween-80 to liquid paraffin, stir and mix thoroughly, then add exosome solution dropwise. During the dropwise addition, stir continuously to form an emulsion, then slowly add 1.5 parts of glutaraldehyde. After the dropwise addition is complete, stir and react at room temperature for 4 hours, then centrifuge to separate the precipitate, wash the precipitate three times with petroleum ether, and freeze-dry to obtain exosome microcapsules.

[0074] Example 6. A method for preparing a dental implant with a highly bioactive surface coating, comprising the following steps:

[0075] Compared with Example 5, this example increases the amount of 3-chloro-2-hydroxypropyltrimethylammonium chloride added in step b;

[0076] The method for preparing the exosome microcapsules includes the following steps:

[0077] a. Dissolve 10 parts by weight of sodium alginate in deionized water and stir until completely dissolved. Then, add sodium hydroxide dropwise to adjust the pH to 9. Under a nitrogen atmosphere, add 5 parts of EDC·HCl and 3 parts of N-hydroxysuccinimide. Stir and mix at room temperature for 30 minutes. Then, slowly add 5 parts of dimethylaminopropylamine. After the addition is complete, stir and react at room temperature for 18 hours. During the reaction, control the pH of the reaction system to 6.5. After the reaction is complete, dialyze the reaction solution using a 10 kDa dialysis bag. After dialysis for 24 hours, the solution is lyophilized to obtain tertiary amine modified sodium alginate.

[0078] b. By weight, 10 parts of tertiary amine modified sodium alginate were dispersed in deionized water, the pH was adjusted to 7.5, 5 parts of 3-chloro-2-hydroxypropyltrimethylammonium chloride were added, and the mixture was stirred for 18 hours. During the reaction, the pH was controlled at 7.5. After the reaction was completed, the product was precipitated with acetone, the precipitate was collected, and lyophilized to obtain quaternized sodium alginate.

[0079] c. By weight, disperse 1 part of exosomes in PBS buffer, mix well, add 10 parts of quaternized sodium alginate and 30 parts of sodium alginate, stir and mix well, and cool to 2~4℃ to obtain exosome solution;

[0080] Add 0.5% by volume of Tween-80 to liquid paraffin, stir and mix thoroughly, then add exosome solution dropwise. During the dropwise addition, stir continuously to form an emulsion, then slowly add 1.5 parts of glutaraldehyde. After the dropwise addition is complete, stir and react at room temperature for 4 hours, then centrifuge to separate the precipitate, wash the precipitate three times with petroleum ether, and freeze-dry to obtain exosome microcapsules.

[0081] Comparative Example 1. A method for preparing a dental implant with a highly bioactive surface coating, comprising the following steps:

[0082] Compared with Example 1, no exosome microcapsules were prepared in this comparative example;

[0083] S1. Preparation of titanium alloy dental implant matrix;

[0084] After the surface of the titanium alloy rod is machined into the required shape, it is cleaned and dried with deionized water and anhydrous ethanol in sequence. Then, the surface is roughened by sandblasting. After that, it is immersed in acid and alkali solutions to activate the surface. After cleaning and drying with deionized water and anhydrous ethanol again, the titanium alloy dental implant matrix is ​​obtained.

[0085] The acid solution is a mixed solution of sulfuric acid solution and hydrochloric acid solution in a volume ratio of 1:1;

[0086] The sulfuric acid solution has a concentration of 45 wt%; the hydrochloric acid solution has a concentration of 10 wt%.

[0087] The alkaline solution is a 10wt% sodium hydroxide solution;

[0088] S2. Preparation of an active polydopamine coating;

[0089] By weight, 100 parts of dopamine hydrochloride were dissolved in deionized water and stirred until completely dissolved. Ammonia was added dropwise to adjust the pH of the mixture to 9. The titanium alloy dental implant substrate was then completely immersed in the mixture. The mixture was heated to 35°C and stirred for 8 hours. The titanium alloy dental implant substrate was then removed, and its surface was washed three times with ultrapure water. After freeze-drying, an active polydopamine coating was formed on its surface, resulting in a dental implant with a highly bioactive surface coating.

[0090] Testing: The hydrophilicity of the dental implants prepared in Examples 1-6 and Comparative Example 1 was tested by water droplet contact angle.

[0091] The culture configuration yielded a bacterial concentration of 1×10⁻⁶. 6 CFU / mL of Porphyromonas gingivalis solution was inoculated onto the surface of dental implants prepared in Examples 1-6 and Comparative Example 1, respectively. After anaerobic culture for 24 h, the surfaces of the dental implants prepared in Examples 1-6 and Comparative Example 1 were washed with BHI liquid medium and sterile water. The washing liquid was collected and inoculated onto BHI plates. After anaerobic culture for 24 h, the antibacterial rate was obtained.

[0092] Meanwhile, a control blank group was set up. After being treated only in step S1, the control blank group was inoculated with Porphyromonas gingivalis solution according to the above steps. The bacterial count obtained after washing and culturing was used as the detection benchmark.

[0093] The formula for calculating the antibacterial rate is as follows:

[0094] Antibacterial rate = (Number of colonies in blank group sample - Number of colonies in experimental group sample) / Number of colonies in blank group sample × 100%;

[0095] The surfaces of the dental implants with highly bioactive surface coatings prepared in Examples 1-6 and Comparative Example 1 were disinfected with 75% ethanol and transferred into 24-well plates. 0.5 mL of osteoblast cell solution was seeded into each well of the 24-well plate. The osteoblast cell solution contained cells in the logarithmic growth phase at a concentration of 1 × 10⁻⁶ cells. 7 / L, after inoculation, the surface of the dental implant was rinsed with PBS buffer after 1, 3 and 7 days of culture. After rinsing, the implant was transferred to a new 24-well culture plate and cultured again. 0.5 mL of cell culture medium and 0.05 mL of LCK-8 detection solution were inoculated into each well. After incubation at 37°C for 2 h, the reaction solution in the well was taken and the absorbance was detected by ultraviolet light using an ELISA reader.

[0096]

[0097] As shown in the table above, based on the experimental results of Examples 1-2 and Comparative Example 1, the antibacterial rate and osteoblast proliferation rate significantly increased after adding exosome microcapsules. This means that the exosome microcapsules prepared in this invention have significant antibacterial properties and bioactivity that promotes osteoblast proliferation. The comparison between Examples 2 and 3 shows that adding quaternized sodium alginate further enhances the antibacterial properties of dental implants. The comparison between Examples 3 and 4 shows that increasing the exosome content further enhances the osteoblast proliferation rate. The data from Examples 5 and 6 show that increasing the content of quaternized functional groups in sodium alginate further enhances the antibacterial properties.

[0098] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A dental implant with a highly bioactive surface coating, characterized in that: The dental implant with a highly bioactive surface coating consists of a titanium alloy dental implant matrix and an active polydopamine coating loaded on its surface. The polydopamine coating contains exosome microcapsules. The method for preparing the exosome microcapsules includes the following steps: a. Dissolve sodium alginate in deionized water and stir until completely dissolved. Then, add sodium hydroxide dropwise to adjust the pH to 8.5-9.

5. Under a nitrogen atmosphere, add EDC·HCl and N-hydroxysuccinimide. Stir and mix at room temperature for 30-45 minutes. Then, slowly add dimethylaminopropylamine. After the addition is complete, stir and react at room temperature for 18-24 hours. During the reaction, control the pH of the reaction system to 6.5-7. After the reaction is complete, dialyze the reaction solution. After dialysis, freeze-dry to obtain tertiary amine modified sodium alginate. b. Disperse the tertiary amine-modified sodium alginate in deionized water, adjust the pH to 7.5-8, add 3-chloro-2-hydroxypropyltrimethylammonium chloride, stir and react for 18-24 hours. During the reaction, control the pH to 7.5-8. After the reaction is complete, precipitate the product with acetone, collect the precipitate, freeze dry it to obtain quaternized sodium alginate. c. Disperse the exosomes in PBS buffer, mix well, add quaternized sodium alginate and sodium alginate, stir and mix well, and cool to 2~4℃ to obtain the exosome solution; Add 0.3-0.5% by volume of Tween-80 to liquid paraffin, stir and mix thoroughly, then add exosome solution dropwise. During the dropwise addition, stir continuously to form an emulsion, then slowly add glutaraldehyde. After the dropwise addition is complete, stir and react at room temperature for 2-4 hours, then centrifuge to separate the precipitate, wash the precipitate 2-3 times with petroleum ether, and freeze-dry to obtain exosome microcapsules.

2. The dental implant with a highly bioactive surface coating according to claim 1, characterized in that: In step a, the amount of each component added, by weight, is 10 parts sodium alginate, 5-8 parts EDC・HCl, 3-5 parts N-hydroxysuccinimide, and 0.5-5 parts dimethylaminopropylamine.

3. A dental implant with a highly bioactive surface coating according to claim 1, characterized in that: In step a, the dialysis bag used during dialysis is 5~10kDa.

4. A dental implant with a highly bioactive surface coating according to claim 1, characterized in that: In step b, the amount of each component added, by weight, is 10 parts of tertiary amine-modified sodium alginate and 1 to 5 parts of 3-chloro-2-hydroxypropyltrimethylammonium chloride.

5. A dental implant with a highly bioactive surface coating according to claim 1, characterized in that: In step c, the amount of each component added, by weight, is 0.5-1 part exosomes, 2-10 parts quaternized sodium alginate, 15-30 parts sodium alginate, and 1.5-5 parts glutaraldehyde.

6. A method for preparing a dental implant with a highly bioactive surface coating as described in any one of claims 1 to 5, characterized in that, Includes the following steps: S1. Preparation of titanium alloy dental implant matrix; After the surface of the titanium alloy rod is machined into the required shape, it is cleaned and dried with deionized water and anhydrous ethanol in sequence. Then, the surface is roughened by sandblasting. After that, it is immersed in acid and alkali solutions to activate the surface. After cleaning and drying with deionized water and anhydrous ethanol again, the titanium alloy dental implant matrix is ​​obtained. S2. Preparation of an active polydopamine coating; Dopamine hydrochloride was dissolved in deionized water and stirred until completely dissolved. Exosome microcapsules were then added and stirred until evenly dispersed. Ammonia was added dropwise to adjust the pH of the mixture to 8.5-9. The titanium alloy dental implant substrate was then completely immersed in the mixture. The mixture was heated to 30-37°C and stirred for 6-12 hours. The titanium alloy dental implant substrate was then removed and its surface was washed with ultrapure water 2-3 times. After freeze-drying, an active polydopamine coating was formed on its surface, resulting in a dental implant with a highly bioactive surface coating.

7. The method for preparing a dental implant with a highly bioactive surface coating according to claim 6, characterized in that: In step S1, the acid solution is a mixed solution of sulfuric acid solution and hydrochloric acid solution in a volume ratio of 1:1; The sulfuric acid solution has a concentration of 45-55 wt%; the hydrochloric acid solution has a concentration of 5-20 wt%.

8. The method for preparing a dental implant with a highly bioactive surface coating according to claim 6, characterized in that: In step S1, the alkaline solution is a sodium hydroxide solution with a concentration of 10~20wt%.

9. The method for preparing a dental implant with a highly bioactive surface coating according to claim 6, characterized in that: In step S2, the mass ratio of dopamine hydrochloride to exosome microcapsules is 100:(1~5).

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