CN115368589A

CN115368589A - Hemostatic material for filling extracted tooth sockets and preparation method thereof

Info

Publication number: CN115368589A
Application number: CN202211033463.9A
Authority: CN
Inventors: 杨雪; 郭刚; 朱晓强; 黄乃进
Original assignee: Nuoymeier Shandong Medical Technology Co ltd
Current assignee: Nuoymeier Shandong Medical Technology Co ltd
Priority date: 2022-08-26
Filing date: 2022-08-26
Publication date: 2022-11-22

Abstract

The invention provides a hemostatic filling material for extracting a dental cavity and a preparation method thereof, which relate to the technical field of medical biomaterials and comprise the following steps: preparing N-hydroxybutyl chitosan; crosslinking N-hydroxybutyl chitosan and aldehydes to obtain crosslinked N-hydroxybutyl chitosan; preparing electrostatic spinning solution from cross-linked N-hydroxybutyl chitosan and hydroxyapatite; carrying out electrostatic spinning by using the electrostatic spinning solution to obtain an electrostatic spinning film; and (4) crushing the electrostatic spinning film to obtain the hemostatic filling material for tooth extraction. The preparation method of the hemostatic material for filling the tooth extraction socket provided by the invention selects the natural polymer material subjected to derivatization treatment, performs gradient weak crosslinking, realizes instantaneous hemostasis, forms blood clot and then gels, and seals hemostasis; meanwhile, hydroxyapatite is wrapped by the temperature-sensitive characteristic of the derivative high polymer material, so that an osteogenic space is stabilized; the nano-scale fiber structure is formed through electrostatic spinning, so that new bone regeneration is effectively guided, and the formation of alveolar bone in the tooth extraction socket is promoted.

Description

Hemostatic material for filling extracted tooth sockets and preparation method thereof

Technical Field

The invention relates to the technical field of medical biomaterials, in particular to a hemostatic material for filling a tooth extraction socket and a preparation method thereof.

Background

Tooth extraction is the most basic operation in oral and maxillofacial surgery, and like other operations, the tooth extraction can cause different degrees of damage to local soft tissues and hard tissues, cause symptoms such as bleeding, swelling, pain, infection, maxillary sinus perforation and the like, and cause more serious complications due to improper treatment. Generally, blood clots can be formed at the position of a tooth extraction socket 15-20min after tooth extraction to block the wound surface, the blood clots have important effects on infiltrating epithelial cells and promoting alveolar bone reconstruction, and the removal of the blood clots obviously delays the healing of the tooth extraction socket, so that sufficient and stable blood clots in the tooth extraction socket are guaranteed, and the tooth extraction socket is of great importance to the repair of soft tissues of the tooth extraction socket.

The existing hemostatic materials for pulling out the dental alveolus are not only non-absorbable materials such as gauze, cotton balls and the like, but also common absorbable hemostatic materials such as gelatin, oxidized cellulose, fibrin, chitosan and collagen and the like, can be absorbed by the hemostatic materials without secondary taking out, have high acceptance of patients, but the hemostatic materials achieve the effect of compression hemostasis only by covering the wound surface, have single function, can not promote the formation of blood clots, can not fix the blood clots after the blood clots are coagulated to be difficult to damage and fall off, are not suitable for patients with a great amount of bleeding and blood coagulation dysfunction in pulling out the dental alveolus, can be degraded in a short time, can not play the roles of sealing and pulling out the dental wound and filling the dental alveolus, and are not beneficial to the regeneration of alveolar bone in the dental alveolus.

Disclosure of Invention

The invention solves the problem that the existing hemostatic material for the tooth extraction socket is not beneficial to regeneration of alveolar bone in the tooth extraction socket.

In order to solve the problems, the invention provides a preparation method of a hemostatic filling material for tooth extraction sockets, which comprises the following steps:

s1: preparing N-hydroxybutyl chitosan by taking chitosan as a raw material;

s2: crosslinking the N-hydroxybutyl chitosan and aldehydes to obtain crosslinked N-hydroxybutyl chitosan;

s3: preparing electrostatic spinning solution from the cross-linked N-hydroxybutyl chitosan and hydroxyapatite;

s4: carrying out electrostatic spinning by using the electrostatic spinning solution to obtain an electrostatic spinning film;

s5: and crushing the electrostatic spinning membrane to obtain the hemostatic filling material for extracting the dental alveolus.

Optionally, the chitosan has a deacetylation degree of 80-94% and a molecular weight of 5000-2000000 Da.

Optionally, step S1 includes the steps of:

s11: preparing alkalized chitosan by taking alkali liquor and the chitosan as raw materials;

s12: adding isopropanol and water into the alkalized chitosan, stirring, adding a phase transfer catalyst, heating in a water bath at 50-85 ℃, and stirring to obtain a chitosan pre-catalysis solution;

s13: adding an etherifying agent into the chitosan precatalyst solution, heating to 50-85 ℃, and reacting to obtain a crude product of the N-hydroxybutyl chitosan;

s14: washing the crude product of the N-hydroxybutyl chitosan by using ethanol, and adjusting the pH value to 6.5-7.5 to obtain a primary product of the N-hydroxybutyl chitosan;

s15: and washing and dialyzing the primary N-hydroxybutyl chitosan product, and then drying in vacuum at 50-80 ℃ to obtain the N-hydroxybutyl chitosan.

Optionally, step S11 includes: dissolving NaOH in water, cooling to 15-30 ℃ in an ice water bath, adding chitosan, stirring, and filtering to obtain the alkalized chitosan.

Optionally, the mass ratio of the alkalized chitosan, the isopropanol and the water in the step S12 is 1: (2-10): (2-15).

Alternatively, the etherifying agent in step S13 is 1, 2-butylene oxide.

Optionally, step S2 includes:

s21: mixing N-hydroxybutyl chitosan with ethanol, wherein the mass concentration of the N-hydroxybutyl chitosan is 1% -30%, so as to obtain a suspension;

s22: adding a cross-linking agent into the suspension, stirring for cross-linking, and performing suction filtration to obtain a cured substance;

s23: and mixing and cleaning the condensate with alcohol, and then carrying out suction filtration and drying to obtain the cross-linked N-hydroxybutyl chitosan.

Optionally, step S3 comprises: dissolving the crosslinked N-hydroxybutyl chitosan in dichloromethane, and adding hydroxyapatite, wherein the mass ratio of the crosslinked N-hydroxybutyl chitosan to the hydroxyapatite is (5-20): (0.1-3), stirring to obtain the electrostatic spinning solution.

Optionally, the process conditions of the electrostatic spinning in step S4 are: the voltage intensity is 25kV, the flow rate is 1.0mL/h, the receiving material is aluminum foil paper, and the distance between the spinning needle and the receiving position is 5 cm-10 cm.

Another object of the present invention is to provide a hemostatic filling material for dental extraction sockets, which is prepared by the above-mentioned method for preparing a hemostatic filling material for dental extraction sockets.

Compared with the prior art, the preparation method of the hemostatic material for extracting the dental pit provided by the invention has the following advantages:

the preparation method of the hemostatic material for filling the tooth extraction socket provided by the invention selects the natural polymer material subjected to derivatization treatment, performs gradient weak crosslinking, realizes instantaneous hemostasis, forms blood clot and then gels, and seals hemostasis; meanwhile, hydroxyapatite is wrapped by the temperature-sensitive characteristic of the derivative high polymer material, so that an osteogenic space is stabilized; the nano-scale fiber structure is formed through electrostatic spinning, so that new bone regeneration is effectively guided, alveolar bone formation in the tooth extraction socket is promoted, nano-particles are obtained through mechanical crushing, and the tooth extraction socket can be conveniently filled without dead angles.

Drawings

FIG. 1 is a scanning electron microscope image of a hemostatic filling material for an extraction socket prepared according to example 1 of the present invention;

FIG. 2 is an infrared spectrum of chitosan and N-hydroxybutyl chitosan of example 1 of the present invention.

Detailed Description

The present invention will now be described in further detail. The embodiments described below are intended to be illustrative of the invention and should not be understood as limiting the invention, and all other embodiments that can be made by one skilled in the art without inventive effort based on the embodiments of the invention shall fall within the scope of protection of the invention.

The existing hemostatic filling material, for example, patent CN112316209A an oral hemostatic and repair material and its preparation method, in the patent, decalcified bone particles are used as a carrier of the oral hemostatic and repair material, the collagen structure contained in the material has an inducing effect on mineral deposition of wound surface bone, and the material can effectively initiate and control mineralization process and promote formation of new bone by combining with growth factors and other bone grafting materials, thereby improving the effect of the oral hemostatic and repair material on inducing regeneration of new bone at the defect site after tooth extraction; the patent can not fill without dead angles and has the problem of rapid degradation; patent CN111849013A discloses a nano-hydroxyapatite-silk fibroin mineralization scaffold, a preparation method and application thereof, wherein the silk fibroin scaffold is obtained by immersing the silk fibroin scaffold in a mineralization liquid for reaction, so that the mineralization scaffold is remarkably improved in hydrophilicity, good in biocompatibility, capable of promoting cell migration and growth, good in mechanical property and good in bone differentiation and induction capacity; although the performance of the scaffold is better than that of the traditional nano hydroxyapatite/silk fibroin composite material, the scaffold can only provide better filling and bone regeneration guiding effects, cannot stop bleeding and needs to be matched with a hemostatic material for use; patent CN110090320B is an extracted tooth pit repairing scaffold with antibacterial activity and a preparation method thereof, the repairing scaffold provided by the patent is a conical structure capable of being matched with an extracted tooth pit, the conical structure is in a form of solidifying by a repairing material, a layer of collagen is attached to the conical bottom, a compact film is obtained by extruding after freeze drying, and the repairing material comprises a collagen-hydroxyapatite compound, collagen and minocycline hydrochloride; although the repairing bracket can realize filling of the tooth extracting socket, the conical structure has strong pertinence and poor plasticity and does not have universal applicability; CN112587729A patent, which is directed to a bone repair material prepared by degreasing and deproteinizing bovine femoral bone to remove substances such as antigens, is used for providing a bone repair material and maintaining the compression resistance and osteoconductivity of the bone repair material; the bone repair material can only guide bone regeneration, needs to be matched with a hemostatic material for use, and is in a discrete state in a tooth extraction socket, so that the bone repair material is not easy to shape.

In conclusion, the existing hemostatic filling material for tooth extraction has the following defects: the function is single, and only hemostasis or bone repair can be realized; the use is inconvenient, the shape is regular, the adaptability of irregular wound surfaces is poor, and no dead-angle filling can be ensured; the bone repair material is easy to disperse, does not have a shaping function, and is difficult to effectively maintain space.

In order to solve the problem that the existing hemostatic filling material for extracting the dental alveolus is not beneficial to regeneration of alveolar bone in the extraction alveolus, the invention provides a preparation method of the hemostatic filling material for extracting the dental alveolus, which comprises the following steps:

s1: preparing N-hydroxybutyl chitosan by taking chitosan as a raw material;

s2: crosslinking N-hydroxybutyl chitosan and aldehydes to obtain crosslinked N-hydroxybutyl chitosan;

s3: preparing electrostatic spinning solution by cross-linking N-hydroxybutyl chitosan and hydroxyapatite;

s5: and (4) crushing the electrostatic spinning film to obtain the hemostatic filling material for tooth extraction.

The chitosan is selectively and chemically modified to prepare a novel chitosan derivative, so that a novel hemostatic filling material for tooth extraction is prepared; the hydroxyapatite is the main inorganic component of human and animal bones, promotes the growth of the bone of the tooth extraction pit, realizes chemical bond combination with organism tissues on an interface, has certain solubility in vivo, can release ions which are harmless to the organism, participates in vivo metabolism, has stimulation or induction effect on hyperosteogeny, can promote the repair of defective tissues, and shows bioactivity.

Specifically, in order to improve the hemostatic function, the application is shown as the following formula,

firstly, by adding chitosan C ₂ -NH ₂ The substitution is carried out, a hydroxybutyl group is introduced, N-hydroxybutyl chitosan rich in hydroxybutyl is obtained, aldehydes are used for crosslinking on the basis, the temperature sensitivity is realized while the performance of chitosan is kept, the material can absorb blood instantly, after blood clots are formed, gelation is carried out, gel sealing hemostasis is formed, meanwhile, temperature sensitivity is realized, stable gel is formed, hydroxyapatite is wrapped, a stable bone forming space is formed, and a good shape of the tooth extraction pit is kept; form nanometer fibrous structure through electrostatic spinning, effectively guide new bone regeneration, promote the formation of drawing out alveolar bone in the tooth nest, mechanical crushing obtains the nanofiber granule, not only helps increasing the area of contact of material and wound department, improves imbibition efficiency, can keep filling shutoff state simultaneously, realizes that no dead angle is filled, is convenient for draw out the tooth nest and fills.

In order to ensure the performance of the hemostatic filling material for extracting the tooth sockets, the deacetylation degree of chitosan is preferably 80-94%, and the molecular weight is 5000-2000000 Da.

Preferably, step S1 of the present application includes the following steps:

s11: preparing alkalized chitosan by taking alkali liquor and chitosan as raw materials;

s13: adding an etherifying agent into the chitosan precatalyst solution, heating to 50-80 ℃, and reacting to obtain a crude N-hydroxybutyl chitosan product;

s15: and washing and dialyzing the primary product of the N-hydroxybutyl chitosan, and then drying the primary product of the N-hydroxybutyl chitosan in vacuum at the temperature of between 50 and 80 ℃ to obtain the N-hydroxybutyl chitosan.

Specifically, preferably, step S11 includes: dissolving NaOH in water, cooling to 15-30 ℃ in ice water bath, adding chitosan, fully stirring, preferably for 3-12 hours, fluffing the chitosan, and filtering to obtain the alkalized chitosan; preferably, the mass ratio of NaOH, water and chitosan in the step is 1:1:1.

further performing precatalysis on the chitosan, specifically, adding isopropanol and water into the alkalized chitosan, preferably, the mass ratio of the alkalized chitosan to the isopropanol to the water in the step S12 is 1: (2-10): (2-15), fully stirring until the alkalized chitosan is uniformly dispersed, adding a phase transfer catalyst, preferably sodium dodecyl sulfate, into the mixture, heating the mixture in a water bath at the temperature of between 50 and 85 ℃, fully stirring, preferably stirring for 3 to 18 hours, and thus obtaining the chitosan pre-catalytic solution.

Further preparing hydroxyalkylated chitosan, adding an etherifying agent to the chitosan precatalyst solution, preferably the etherifying agent in step S13 is 1, 2-epoxybutaneAlkyl, preferably dropwise adding etherifying agent at the speed of 20-80 drops/s, heating to 50-80 ℃, carrying out etherification reaction, controlling the reaction time to 12-36 h, and reacting at C ₂ -NH ₂ Introducing a hydroxybutyl group to obtain a crude product of the N-hydroxybutyl chitosan.

In order to stop the reaction, the crude product of the N-hydroxybutyl chitosan is washed by ethanol (preferably 75 to 100 mass percent), and the pH value is adjusted to 6.5 to 7.5 by 0.1 to 1mol/L hydrochloric acid, so as to obtain the initial product of the N-hydroxybutyl chitosan.

Purifying the product, preferably performing centrifugal washing on the product for 3-5 times by using absolute ethyl alcohol or acetone, dialyzing the product for 24-72 hours in deionized water by using a dialysis bag with the molecular weight cutoff of 3000, and performing vacuum drying on the product at the temperature of 50-80 ℃ after the dialysis is finished to obtain the N-hydroxybutyl chitosan.

The application further carries out weak crosslinking on hydroxyl groups of the N-hydroxybutyl chitosan and aldehydes so as to achieve the purposes of instantaneous blood suction, blood clot stabilization and complete gelation, sealing and hemostasis of the material, and in addition, stable osteogenic space is formed by the temperature-sensitive wrapping of nano-hydroxyapatite by the N-hydroxybutyl chitosan; specifically, in the present application, preferably, step S2 includes:

s21: mixing N-hydroxybutyl chitosan with ethanol to obtain a suspension, wherein the mass concentration of the N-hydroxybutyl chitosan is 1% -30%;

s22: adding a cross-linking agent into the suspension, stirring for cross-linking, and performing suction filtration to obtain a cured substance; preferably, the cross-linking agent is glyoxal, and the stirring and cross-linking time is 1-6 h;

s23: mixing and cleaning the condensate with alcohol, filtering, and drying to obtain cross-linked N-hydroxybutyl chitosan; the condensate is preferably mixed with an alcohol in a ratio of 1: mixing and cleaning for 2-5 times at a ratio of 1-5, adsorbing excessive cross-linking agent, filtering to remove cleaning solution, and drying at 30-55 deg.C or vacuum drying to obtain cross-linked N-hydroxybutyl chitosan.

To promote alveolar bone regeneration, step S3 of the present application preferably includes: dissolving the cross-linked N-hydroxybutyl chitosan in dichloromethane, and adding hydroxyapatite, wherein the mass ratio of the cross-linked N-hydroxybutyl chitosan to the hydroxyapatite is (5-20): (0.1-3), stirring to obtain the electrostatic spinning solution.

The preferred process conditions for electrostatic spinning in step S4 in the present application are: the voltage intensity is 25kV, the flow rate is 1.0mL/h, the receiving material is aluminum foil paper, and the distance between the spinning needle and the receiving position is 5 cm-10 cm.

The nanofiber structure formed through electrostatic spinning can effectively guide new bone regeneration and promote the formation of alveolar bone in the tooth extraction socket.

The hemostatic filling material for extracting the dental alveolus provided by the invention selects a natural polymer material subjected to derivatization treatment, performs gradient weak crosslinking, realizes instantaneous hemostasis, forms blood clots, then gels, and seals hemostasis; meanwhile, hydroxyapatite is wrapped by the temperature-sensitive characteristic of the derivative high polymer material, so that an osteogenic space is stabilized; the nano-scale fiber structure is formed through electrostatic spinning, so that new bone regeneration is effectively guided, alveolar bone formation in the tooth extraction socket is promoted, nano-particles are obtained through mechanical crushing, and the tooth extraction socket can be conveniently filled without dead angles.

Specifically, the application is realized by adding chitosan C ₂ -NH ₂ The substitution is carried out, a hydroxybutyl group is introduced to obtain the N-hydroxybutyl chitosan rich in hydroxybutyl, the hydroxyl group of the N-hydroxybutyl chitosan and aldehydes are subjected to weak crosslinking to achieve the purposes of instantaneous blood absorption, blood clot stabilization, material full gelation, sealing and hemostasis, and in addition, a stable osteogenic space is formed by the temperature-sensitive wrapping of nano-scale hydroxyapatite of the N-hydroxybutyl chitosan; in the aspect of practicability, the nano microfilament structure capable of guiding bone regeneration is obtained through an electrostatic spinning process, and after mechanical crushing, the contact area is increased, so that the material can be molded randomly, and the performance of filling without dead angles is met.

The hemostatic material for filling the tooth extraction socket provided by the invention can stop bleeding and has the function of guiding bone regeneration; the hemostatic effect not only plugs the wound to achieve the effect of exogenous hemostasis, but also can gather the effective components such as platelets, leucocytes and the like in the blood, promote the formation of blood clots at the injury part and stimulate endogenous hemostasis; the blood clot and the hemostatic material form a stable structure at the wound, so that the effects of quickly coagulating blood, stabilizing the blood clot and protecting the wound of the tooth extraction pit are achieved; meanwhile, the hemostatic filling material can promote cell growth, osteoblast differentiation and formation of bone trabecula, further realize filling of the tooth extraction socket, prevent gingival atrophy at the tooth extraction position, and is an ideal hemostatic filling material for the tooth extraction socket.

Example 1

S11: dissolving NaOH in purified water with equal mass, cooling to 20 ℃ in an ice water bath, adding chitosan with equal mass, fully stirring for 5 hours, and fluffing the chitosan to obtain alkalized chitosan; wherein the chitosan has deacetylation degree of 85% and molecular weight of 1200000Da;

s12: adding 10g of isopropanol and 40g of purified water (the ratio of the alkalized chitosan to the isopropanol: the purified water =1: 2) into 5g of alkalized chitosan, heating in a water bath at 60 ℃, fully stirring for 5h, adding 0.1g of sodium dodecyl sulfate, and continuously stirring for 3h to obtain a chitosan precatalyst solution;

s13: dropwise adding 100mL of 1, 2-epoxybutane into the chitosan precatalyst solution, wherein the dropwise adding speed is 50 drops/s, and carrying out etherification reaction at 60 ℃ for 12 hours to obtain a crude product of the N-hydroxybutyl chitosan;

s14: washing the crude product of the N-hydroxybutyl chitosan by using absolute ethyl alcohol, and then adjusting the pH to 7 by using a 0.5M hydrochloric acid solution to obtain a primary product of the N-hydroxybutyl chitosan;

s15: washing the primary product of N-hydroxybutyl chitosan with anhydrous ethanol for 3 times, dialyzing with a dialysis bag with molecular weight cutoff of 3000 in deionized water for 48h, and vacuum drying at 50 deg.C to obtain N-hydroxybutyl chitosan;

s21: dispersing N-hydroxybutyl chitosan in absolute ethyl alcohol, wherein the mass concentration of the N-hydroxybutyl chitosan is 15%, and stirring for 30min to obtain a suspension;

s22: adding glyoxal with the mass fraction of 0.03% into the suspension, stirring and crosslinking for 3 hours, and performing suction filtration to obtain a cured substance;

s23: adding ethanol with the weight 3 times of that of the condensate, washing for 3 times, removing the redundant cross-linking agent, washing, filtering to remove absolute ethanol, and drying in vacuum at 50 ℃ to obtain the cross-linked N-hydroxybutyl chitosan;

s3: dissolving crosslinked N-hydroxybutyl chitosan in 50mL of dichloromethane, adding 1g of hydroxyapatite, and stirring to obtain an electrostatic spinning solution;

s4: carrying out electrostatic spinning by using electrostatic spinning solution, adjusting voltage and spinning distance, carrying out electrostatic spinning under the conditions of voltage intensity of 25kV and flow rate of 1.0mL/h, and receiving by using aluminum foil paper to obtain an electrostatic spinning film;

s5: and (3) drying the electrostatic spinning film in vacuum at 35 ℃, and mechanically crushing the electrostatic spinning film to obtain nano fiber particles so as to obtain the hemostatic filling material for extracting the dental alveolus.

The scanning electron microscope image of the hemostatic filling material for tooth extraction socket prepared in this example is shown in FIG. 1.

Example 2

S11: dissolving NaOH in purified water with equal mass, cooling to 15 ℃ in an ice water bath, adding chitosan with equal mass, fully stirring for 3 hours, and fluffing the chitosan to obtain alkalized chitosan; wherein the deacetylation degree of chitosan is 85%, and the molecular weight is 50000Da;

s12: adding 25g of isopropanol and 60g of purified water (alkalized chitosan: isopropanol: purified water =1: 12) to 5g of alkalized chitosan, heating in a water bath at 75 ℃, adding 0.1g of sodium dodecyl sulfate after stirring sufficiently for 2h, and continuing stirring for 5h to obtain a chitosan precatalyst solution;

s13: dropwise adding 80mL of 1, 2-epoxybutane into the chitosan precatalyst solution at the dropping speed of 20 drops/s, and carrying out etherification reaction for 15h at the temperature of 80 ℃ to obtain a crude product of the N-hydroxybutyl chitosan;

s14: washing the crude product of the N-hydroxybutyl chitosan by using 95% ethanol, and then adjusting the pH to 7 by using a 0.5M hydrochloric acid solution to obtain a primary product of the N-hydroxybutyl chitosan;

s15: washing the primary product of N-hydroxybutyl chitosan with anhydrous ethanol for 3 times, dialyzing in deionized water for 65h with a dialysis bag with molecular weight cutoff of 3000, and vacuum drying the product at 70 ℃ after dialysis to obtain N-hydroxybutyl chitosan;

s21: dispersing N-hydroxybutyl chitosan in absolute ethyl alcohol, wherein the mass concentration of the N-hydroxybutyl chitosan is 15%, and stirring for 50min to obtain a suspension;

s22: adding glyoxal with the mass fraction of 0.05% into the suspension, stirring and crosslinking for 2 hours, and performing suction filtration to obtain a cured substance;

s23: adding ethanol with the weight 5 times of that of the condensate, cleaning for 3 times, removing the redundant cross-linking agent, cleaning, then performing suction filtration to remove absolute ethanol, and performing vacuum drying at 50 ℃ to obtain the cross-linked N-hydroxybutyl chitosan;

s5: and (3) drying the electrostatic spinning membrane in vacuum at 40 ℃, and mechanically crushing the electrostatic spinning membrane to obtain nano fiber particles to obtain the hemostatic filling material for extracting the dental alveolus.

Example 3

S11: dissolving NaOH in purified water with equal mass, cooling to 30 ℃ in an ice water bath, adding chitosan with equal mass, fully stirring for 12 hours, and fluffing the chitosan to obtain alkalized chitosan; wherein the chitosan has deacetylation degree of 90% and molecular weight of 300000Da;

s12: adding 50g of isopropanol and 10g of purified water (the alkalized chitosan: isopropanol: purified water =1: 10) into 5g of alkalized chitosan, heating in a water bath at 50 ℃, fully stirring for 2h, adding 0.1g of sodium dodecyl sulfate, and continuously stirring for 18h to obtain a chitosan precatalyst solution;

s13: dropwise adding 80mL of 1, 2-epoxybutane into the chitosan precatalysis solution at a dropping speed of 80 drops/s, and carrying out etherification reaction at 50 ℃ for 36h to obtain a crude product of N-hydroxybutyl chitosan;

s15: washing the primary product of N-hydroxybutyl chitosan with anhydrous ethanol for 3 times, dialyzing in deionized water for 12h with a dialysis bag with molecular weight cutoff of 3000, and vacuum drying the product at 80 deg.C to obtain N-hydroxybutyl chitosan;

s3: dissolving crosslinked N-hydroxybutyl chitosan in 40mL of dichloromethane, adding 0.5g of hydroxyapatite, and stirring to obtain an electrostatic spinning solution;

Comparative example 1

S1: dissolving chitosan in 50mL of dichloromethane, adding 1g of hydroxyapatite, and stirring to obtain an electrostatic spinning solution;

Comparative example 2

s3: dissolving crosslinked N-hydroxybutyl chitosan in 50mL of dichloromethane to obtain an electrostatic spinning solution;

s5: and (3) drying the electrostatic spinning membrane in vacuum at 35 ℃, and mechanically crushing the electrostatic spinning membrane to obtain nano fiber particles to obtain the hemostatic filling material for extracting the dental alveolus.

Test example 1

The absorption rate, absorption time, elastic modulus and viscous modulus of the hemostatic materials of the examples and the comparative examples are respectively detected and compared, and the test data are shown in table 1:

TABLE 1

From the data, the hemostatic filling material prepared by the embodiments of the invention has better liquid absorption performance; the gel formed after the material stanchs can be firmly filled in the tooth extraction pit through the elastic modulus and the viscous modulus, so that the hemostatic filling material provided by the invention can instantly absorb blood to form gel sealing hemostasis, and meanwhile, the temperature is sensitive to form stable gel to wrap hydroxyapatite to form a stable osteogenic space.

Compared with the hemostatic filling material in the example 1, the hemostatic filling material provided in the comparative example 1 does not chemically modify chitosan, and the prepared hemostatic filling material only maintains the liquid absorption performance of the chitosan, and cannot play a role in sealing the tooth extraction socket without support.

Compared with the hemostatic filling material in example 1, the hemostatic filling material provided in comparative example 2 has no obvious difference in liquid absorption capacity, support property and blocking effect because hydroxyapatite is not added, but cannot play a role in guiding bone regeneration because hydroxyapatite is not added.

Test example 2: cytotoxicity assay

Each of the examples, comparative examples, negative controls (polyethylene, 1mL of cell culture medium per 6cm2 of negative control, extracted at 37 ℃ for 24h at 60 rpm), positive controls (10% DMSO solution, ready to use), leachate and vehicle controls were placed in wells of L929 mouse fibroblast cells (MEF) and cultured in 5% CO2, 37 ℃ cell culture lines, and evaluated by MTT, as shown in Table 2.

Under the experimental conditions, the cell survival rate of the test sample group exceeds 90%, and the test sample group has low cytotoxicity and no potential cytotoxicity.

TABLE 2

Test example 3: infrared characterization

The chitosan and the N-hydroxybutyl chitosan sample of example 1 were ground and then made into thin film disks by KBr sheeting, and the samples were analyzed by fourier transform infrared spectrometer at a wavelength of 400-4000cm "1 to obtain an infrared spectrum, as shown in fig. 2.

As can be seen from FIG. 2, after chitosan modification, 3363cm ^-1 The strong peak is still remained, which belongs to the superposition of the stretching vibration absorption peak of-OH and the stretching vibration absorption peak of N-H; at 2890cm ^-1 And 1461cm ^-1 Obvious new absorption peaks appear at the positions, namely C-H stretching vibration and asymmetric deformation respectively, which shows that-CH is added after modification ₃ 、-CH ₂ I.e. introduction of hydroxybutyl groups, in the range of 1000-1200cm ^-1 No significant change in absorption peaks within the range is due to C ₆ -OH and C ₄ the-OH is not substituted, the absorption peak is not obviously enhanced or reduced, and the chitosan is at 1461cm ^-1 The absorption peak of C-N is changed, which indicates that the reaction is carried out at C ₂ -NH ₂ The above.

Although the present disclosure has been described above, the scope of the present disclosure is not limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present disclosure, and such changes and modifications will fall within the scope of the present invention.

Claims

1. A preparation method of a hemostatic filling material for extracting a dental cavity is characterized by comprising the following steps:

s1: preparing N-hydroxybutyl chitosan by taking chitosan as a raw material;

2. The method for preparing a hemostatic filling material for tooth extraction cavity as claimed in claim 1, wherein the degree of deacetylation of chitosan is 80-94%, and the molecular weight is 5000-2000000 Da.

3. The method for preparing the hemostatic filling material for tooth extraction sockets as claimed in claim 1, wherein the step S1 comprises the following steps:

s13: adding an etherifying agent into the chitosan precatalyst solution, heating to 50-80 ℃, and reacting to obtain a crude product of the N-hydroxybutyl chitosan;

4. The method for preparing hemostatic filling material for extracting dental fossa according to claim 3, wherein the step S11 comprises: dissolving NaOH in water, cooling to 15-30 ℃ in ice water bath, adding chitosan, stirring, and filtering to obtain the alkalized chitosan.

5. The method for preparing a hemostatic filling material for a dental extraction socket as claimed in claim 3, wherein the mass ratio of the alkalized chitosan, the isopropanol and the water in the step S12 is 1: (2-10): (2-15).

6. The method for preparing a hemostatic filling material for dental extraction sockets as claimed in claim 3, wherein the etherifying agent in the step S13 is 1, 2-butylene oxide.

7. The method for preparing a hemostatic filling material for a dental extraction socket according to any one of claims 1 to 6, wherein the step S2 comprises:

8. The method for preparing a hemostatic filling material for dental extraction sockets as claimed in claim 7, wherein the step S3 comprises: dissolving the crosslinked N-hydroxybutyl chitosan in dichloromethane, and adding hydroxyapatite, wherein the mass ratio of the crosslinked N-hydroxybutyl chitosan to the hydroxyapatite is (5-20): (0.1-3), stirring to obtain the electrostatic spinning solution.

9. The method for preparing the hemostatic filling material for tooth extraction socket according to claim 7, wherein the electrostatic spinning in step S4 comprises the following process conditions: the voltage intensity is 25kV, the flow rate is 1.0mL/h, the receiving material is aluminum foil paper, and the distance between the spinning needle and the receiving position is 5 cm-10 cm.

10. An extracted dental pit hemostatic filling material, which is prepared by the method for preparing an extracted dental pit hemostatic filling material according to any one of claims 1 to 9.