CN114306718A - Self-adhesive composite patch for repairing wound of dental extraction cavity and preparation method thereof - Google Patents
Self-adhesive composite patch for repairing wound of dental extraction cavity and preparation method thereof Download PDFInfo
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- CN114306718A CN114306718A CN202111587261.4A CN202111587261A CN114306718A CN 114306718 A CN114306718 A CN 114306718A CN 202111587261 A CN202111587261 A CN 202111587261A CN 114306718 A CN114306718 A CN 114306718A
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Abstract
The invention relates to a self-adhesive composite patch for repairing a wound of a dental extraction cavity and a preparation method thereof. The self-adhesive composite patch for the wound repair of the dental cavity comprises a wound filling layer and an adhesive blocking layer which are sequentially and compositely connected; the wound filling layer is made of a biological sponge material; the adhesive barrier layer includes a polymer fiber layer and a biogum layer. The self-adhesion composite patch has the functions of filling and stopping bleeding of the tooth extraction pit and closing the wound, can quickly suck blood in the tooth extraction pit by a wound filling layer consisting of biological sponge and realize the function of stopping bleeding after the tooth extraction operation in a mode of promoting the formation of blood clots of a human body, can effectively isolate the tooth extraction pit from the oral cavity to form a relatively closed wound healing environment, and prevents food residues or fine foreign matters in the oral cavity from entering the tooth extraction pit.
Description
Technical Field
The invention belongs to the field of medical materials, and particularly relates to a self-adhesive composite patch for repairing a wound of a dental extraction cavity and a preparation method thereof.
Background
The materials for extracting the dental socket and repairing the dental socket on the market at present are mainly divided into a filling type material and a covering type material in action forms. The filling material usually exerts the hemostatic effect by mechanically pressing the bleeding part, for example, for conventional dental extraction, a tampon or gauze is usually used for clinical treatment by pressing or clenching to stop bleeding. Iodoform gauze is another commonly used hemostatic material for dental extraction cavity filling. The iodoform sliver has the characteristics of soft texture, strong plasticity and the like, and is easy to fill the whole tooth extraction socket after tooth extraction. The free iodide ion dissolved out from the sliver after filling also has certain sterilization and anti-infection capability. In addition, at present, a sponge plug material is also applied to the filling repair of the tooth extraction socket, and the components of the sponge plug material mainly comprise gelatin, oxidized cellulose, chitosan and collagen
And the like. The sponge plug-shaped filling material generally has a porous structure, can quickly absorb blood in the tooth extraction socket, promotes the absorption and aggregation of platelets, and achieves the aim of stopping bleeding. The covering material does not usually have the function of hemostasis, and the main function of the covering material is to prevent foreign matters such as food residues from falling into the tooth extraction socket and prevent local discomfort or inflammation caused by the foreign matters in the tooth extraction socket. The main components of the covering material are mostly natural resin, silicon rubber or other composite materials, and the covering material has certain adhesion capability and plays a role in closing the wound of tooth extraction in a covering mode.
In the prior art, the hemostatic filling material represented by cotton strips, gauze and iodoform yarns is not degradable in the tooth extraction cavity, and needs to be taken out by a secondary operation, and even needs to be taken out in several times under the condition of tooth extraction cavity with serious bleeding or undefined hemostatic effect, so that the wound healing of the tooth extraction cavity is greatly delayed. Particularly for the iodoform sliver, although the addition of the iodide is beneficial to improving the anti-infection performance of the sliver, the iodine-containing sliver has irritation to the oral cavity after being filled, and is not easy to be accepted by doctors and patients. Sponge plug-like filling materials containing gelatin, oxidized cellulose, chitosan, collagen and the like as main components need to be filled in a large amount to fill the tooth extraction socket, but because such materials often have imbibition expansibility, wound healing can be affected after filling expansion. Overfilling of the sponge plug-like material also causes local abnormalities resulting from nerve compression when a portion of the affected teeth are in close relationship with the mandibular nerve canal. Sponge plug-like filling materials tend to maintain the stability of the material in the extraction socket by increasing the degree of cross-linking of the material, but this can prolong the in vivo degradation time of the filling material and affect the alveolar bone repair process. Meanwhile, the introduction of the chemical cross-linking agent also brings uncertainty to the healing process of the wound. In addition, the covering material prepared by natural resin, silicon rubber or other composite materials can only play a role in closing the tooth extraction wound generally, and almost has no hemostatic and repairing effect on the tooth extraction socket.
Disclosure of Invention
In order to solve the problems in the prior art, the invention provides a self-adhesive composite patch for repairing a wound of a dental extraction socket and a preparation method thereof. The self-adhesive composite patch for repairing the wound of the dental alveolus not only realizes multiple functions of hemostasis, repair and obstruction, but also has good biological safety, degradability and operability in operation.
The invention provides a self-adhesive composite patch for repairing a wound of a dental alveolus, which comprises a wound filling layer and an adhesive blocking layer which are sequentially and compositely connected.
Preferably, the wound packing layer is made of a bio-sponge material.
Preferably, the adhesive barrier layer comprises a polymeric fiber layer and a biogum layer; the wound filling layer, the biological adhesive layer and the polymer fiber layer are sequentially and compositely connected.
Specifically, the wound filling layer is made of a biological sponge material, is cylindrical (or in other shapes), has a height of 3-5 mm and a diameter of 1-1.5 cm; the sticky blocking layer is composed of polymer fibers and biological glue, is rectangular, and has the length of 4cm, the width of 1.5-2 cm and the thickness of 1-3 mm. The wound filling layer is positioned in the middle of the sticky blocking layer. The biological glue has the same components as the biological sponge material and is crosslinked gelatin, and the biological glue has the function of adhering the wound filling layer and the polymer fiber layer.
Based on the same technical concept, the invention also provides a preparation method of the self-adhesive composite patch for the wound repair of the dental extraction cavity, which comprises the following steps:
(I) preparing a wound packing layer, comprising the following steps:
(1) dissolving biomedical gelatin in reverse osmosis water to obtain gelatin solution;
(2) adding sodium hydroxide into the gelatin solution to adjust the pH, then adding tannic acid, keeping the temperature and stirring to obtain a cross-linked gelatin solution;
(3) freezing and drying the crosslinked gelatin to obtain the wound filling layer;
(II) preparing a polymer fiber layer comprising the steps of:
(S1) dissolving polycaprolactone in ethyl acetate to obtain a polycaprolactone solution;
(S2) carrying out electrostatic spinning on the polycaprolactone solution to obtain a polymer fiber layer;
(III) preparing a self-adhesive composite patch for dental cavity wound repair, comprising the following steps:
(SS 1) coating the crosslinked gelatin on the adhesive barrier layer to cool the gelatin, and adhering the gelatin with the wound filling layer to obtain a semi-finished product;
(SS 2) drying the semi-finished product in vacuum to obtain the self-adhesive composite patch for the wound repair of the dental extraction pit.
It is emphasized that the wound filling layer can be replaced or mixed by components with water absorption and hemostasis performances such as oxidized cellulose, chitosan, starch, polyethylene glycol, polyvinyl alcohol and collagen according to the actual requirements of the oral health condition, the prior history condition, the depth of the extracted tooth socket and the like of the patient, so that the personalized treatment of the patient is realized.
Similarly, the polymer fiber layer material can be replaced by one or more materials of polylactic acid (PLA), polylactic acid-glycolic acid copolymer (PLGA), polyethylene glycol-caprolactone copolymer (PEG-PCL), polyamino acid (PAA), Polyurethane (PU) and the like which have certain hydrophobicity, good biocompatibility and degradability according to the needed hardness, air permeability and practical processing difficulty of the patch.
Preferably, in the step (1), the dissolving temperature is 55-60%oC, the concentration of the gelatin is 1-8 wt.%.
Preferably, in the step (2), the pH is adjusted to 10, the weight ratio of the tannic acid to the gelatin is 0.06-0.08: 1, and the heat preservation is 43-45oAnd C, stirring for 50-60 min.
Preferably, in the step (3), the freezing temperature is-20 to-18oAnd C, drying for 22-24 hours.
Preferably, in the step (S1), the concentration of the polycaprolactone solution is 18-20 wt.%.
Preferably, in the step (S2), the electrospinning conditions are: the external high voltage is 10-20 kV, the receiving distance is 13-15 cm, and the liquid inlet speed is 0.8-1.0 mL/h. The basic principle of the step is analyzed as follows: a strong electrostatic field is generated between the spinning nozzle and the receiving device, liquid drops at the outlet of the spraying nozzle are acted by coulomb force in the electrostatic field, and the surface charges are repelled. The polycaprolactone solution of 18-20 wt.% is pulled to form polymer fibers with lengths distributed between 100-500 nm due to the fact that the polycaprolactone solution is high in viscosity and entanglement exists among molecular chains. The fibers are formed into a polymer fiber layer on the receiving device in a free-stacking mode, and the polymer fiber layer can be cut into corresponding sizes in subsequent processes according to needs.
The invention has the beneficial effects that:
1. the self-adhesive composite patch for repairing the wound of the tooth extraction pit has the functions of filling and stopping bleeding of the tooth extraction pit and closing the wound, and the wound filling layer consisting of the biological sponge can quickly suck blood in the tooth extraction pit and realize the function of stopping bleeding after tooth extraction in a mode of promoting the formation of blood clots of a human body. The biological sponge used by the wound filling layer is cross-linked gelatin aerogel, and the hemostatic function can be realized under the condition of a small amount of filling due to the strong water absorption effect caused by the ultrahigh porosity of the biological sponge. And the biological sponge can be separated from the patch-adhered barrier layer within a week and completely degraded without taking out the biological sponge after a secondary operation. The reduction of the filling amount and the excellent degradation property do not influence the wound healing.
2. The sticky blocking layer polymer has strong hydrophobicity, and can effectively isolate the alveolar fossa from the oral cavity to form a relatively closed wound healing environment after being processed into a compact stacked network structure formed by nano-scale fibers and attached to the surface of a wound for tooth extraction, so that food residues or fine foreign matters in the oral cavity are prevented from entering the alveolar fossa, and further, the inflammation in the postoperative alveolar fossa is prevented to a certain extent. The nanometer fiber compact network processed by the polymer surpasses the existing covering type resin, silicon rubber and other materials in the market in flexibility, barrier property and air permeability.
3. Compared with the existing pure filling type or covering type materials in the market, the self-adhesive composite patch for repairing the wound of the dental alveolus not only realizes multiple functions of hemostasis, repair and obstruction, but also has good biological safety, degradability and operability in operation.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.
Fig. 1 is a schematic structural view of the self-adhesive composite patch for extraction wound repair according to the present invention.
Fig. 2 is a schematic view of the use of the self-adhesive composite patch for extraction wound repair of the dental socket according to the present invention.
Fig. 3 is a photograph of the wound packing layer (bio-sponge material) of the present invention taken up water for 1s and 10 s.
Reference numbers in the figures:
1-a wound packing layer; 2-sticking the barrier layer; 21-a biological glue layer; 22-polymer fiber layer.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention will be described in detail below. It is to be understood that the described embodiments are merely exemplary of the invention, and not restrictive of the full scope of the invention. All other embodiments, which can be derived by a person skilled in the art from the examples given herein without any inventive step, are within the scope of the present invention.
Example 1
The embodiment provides a from gluing compound paster for drawing out dental cavity wound repair, including wound filling layer 1 and the gluing barrier layer 2 of compound connection in proper order.
As an alternative embodiment, the wound packing layer 1 is made of a bio-sponge material.
As an alternative embodiment, the adhesive barrier layer 2 comprises a bio-glue layer 21 and a polymer fiber layer 22; the wound filling layer 1, the biological adhesive layer 21 and the polymer fiber layer 22 are sequentially and compositely connected.
Example 2
The embodiment provides a preparation method of a self-adhesive composite patch for dental cavity extraction wound repair, which comprises the following steps:
(I) preparing a wound packing layer, comprising the following steps:
(1) at 60oDissolving biomedical gelatin in reverse osmosis water under the water bath condition to obtain a gelatin solution with the concentration of 1 wt.%;
(2) adding sodium hydroxide to the gelatin solution, adjusting the pH of the solution to 10, adding tannic acid (tannic acid to gelatin weight ratio of 0.06: 1) at 43oC, stirring for 60min under heat preservation to obtain a cross-linked gelatin solution;
(3) the crosslinked gelatin was placed in a mold (mold is a cylindrical cavity with a radius of 0.75 cm and a height of 0.5 cm) and cooled toAfter room temperature, the mixture was placed at-20 deg.CoC, freezing and finally drying for 24 hours to obtain the wound filling layer;
(II) preparing a polymer fiber layer comprising the steps of:
(S1) dissolving polycaprolactone in ethyl acetate to obtain a polycaprolactone solution with the concentration of 20 wt.%;
(S2) under the conditions that the external high voltage is 10 kV, the receiving distance is 13 cm and the liquid inlet speed is 0.8 mL/h, carrying out electrostatic spinning on the polycaprolactone solution to obtain a polymer fiber layer;
(III) preparing a self-adhesive composite patch for dental cavity wound repair, comprising the following steps:
(SS 1) applying the cross-linked gelatin to the tacky barrier layer at 4oC, cooling the gel to generate adhesiveness, and adhering the gel to the wound filling layer to obtain a semi-finished product;
(SS 2) drying the semi-finished product in vacuum for 12h to obtain the self-adhesive composite patch for the wound repair of the dental extraction pit.
Example 3
The embodiment provides a preparation method of a self-adhesive composite patch for dental cavity extraction wound repair, which comprises the following steps:
(I) preparing a wound packing layer, comprising the following steps:
(1) at 55oDissolving biomedical gelatin in reverse osmosis water under the water bath condition to obtain gelatin solution with the concentration of 8 wt.%;
(2) adding sodium hydroxide to the gelatin solution, adjusting the pH of the solution to 10, adding tannic acid (tannic acid to gelatin weight ratio of 0.08: 1) at 45oC, stirring for 50min under heat preservation to obtain a cross-linked gelatin solution;
(3) placing the crosslinked gelatin into a mold (the mold is a cylindrical cavity with a radius of 0.75 cm and a height of 0.5 cm), cooling to room temperature, and placing at-18 deg.CoC, freezing and finally drying for 22 hours to obtain the wound filling layer;
(II) preparing a polymer fiber layer comprising the steps of:
(S1) dissolving polycaprolactone in ethyl acetate to obtain a polycaprolactone solution with the concentration of 18 wt%;
(S2) under the conditions that the external high voltage is 20 kV, the receiving distance is 15 cm and the liquid inlet speed is 1.0 mL/h, carrying out electrostatic spinning on the polycaprolactone solution to obtain a polymer fiber layer;
(III) preparing a self-adhesive composite patch for dental cavity wound repair, comprising the following steps:
(SS 1) applying the cross-linked gelatin to the tacky barrier layer at 4oC, cooling the gel to generate adhesiveness, and adhering the gel to the wound filling layer to obtain a semi-finished product;
(SS 2) drying the semi-finished product in vacuum for 12h to obtain the self-adhesive composite patch for the wound repair of the dental extraction pit.
Finally, the invention also verifies the water absorption performance of the biological sponge material used as the wound filling layer for 1s and 10s, and the following figure 3 shows that: the biological sponge can quickly adsorb aqueous solution and has excellent hydrophilicity; the gel is in a gel state after absorbing water, which is beneficial to forming good blood clots for drawing the tooth sockets at the same level.
The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present invention, and all the changes or substitutions should be covered within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the appended claims.
Claims (9)
1. A self-adhesive composite patch for repairing a wound of a dental cavity is characterized by comprising a wound filling layer and an adhesive blocking layer which are sequentially and compositely connected.
2. The self-adhesive composite patch for extraction socket wound repair of claim 1, wherein the wound filling layer is made of a bio-sponge material.
3. The self-adhesive composite patch for extraction wound repair of a dental socket according to claim 1, wherein the adhesive barrier layer comprises a polymer fiber layer and a bio-adhesive layer; the wound filling layer, the biological adhesive layer and the polymer fiber layer are sequentially and compositely connected.
4. The method for preparing the self-adhesive composite patch for wound repair of the dental extraction socket according to claim 3, comprising the steps of:
(I) preparing a wound packing layer, comprising the following steps:
(1) dissolving biomedical gelatin in reverse osmosis water to obtain gelatin solution;
(2) adding sodium hydroxide into the gelatin solution to adjust the pH, then adding tannic acid, keeping the temperature and stirring to obtain a cross-linked gelatin solution;
(3) freezing and drying the crosslinked gelatin to obtain the wound filling layer;
(II) preparing a polymer fiber layer comprising the steps of:
(S1) dissolving polycaprolactone in ethyl acetate to obtain a polycaprolactone solution;
(S2) carrying out electrostatic spinning on the polycaprolactone solution to obtain a polymer fiber layer;
(III) preparing a self-adhesive composite patch for dental cavity wound repair, comprising the following steps:
(SS 1) coating the crosslinked gelatin on the adhesive barrier layer to cool the gelatin, and adhering the gelatin with the wound filling layer to obtain a semi-finished product;
(SS 2) drying the semi-finished product in vacuum to obtain the self-adhesive composite patch for the wound repair of the dental extraction pit.
5. The preparation method of the self-adhesive composite patch for wound healing of the dental extraction socket according to claim 4, wherein in the step (1), the dissolving temperature is 55-60%oC, the concentration of the gelatin is 1-8 wt.%.
6. According toThe preparation method of the self-adhesive composite patch for wound repair of the dental caries-out wound, according to the claim 4, is characterized in that in the step (2), the pH is adjusted to 10, the weight ratio of the tannic acid to the gelatin is 0.06-0.08: 1, and the heat preservation is 43-45oAnd C, stirring for 50-60 min.
7. The preparation method of the self-adhesive composite patch for the wound healing of the dental socket according to claim 4, wherein in the step (3), the freezing temperature is-20 to-18%oAnd C, drying for 22-24 hours.
8. The method for preparing a self-adhesive composite patch for wound repair of dental caries according to claim 4, wherein in the step (S1), the concentration of the polycaprolactone solution is 18-20 wt.%.
9. The method for preparing a self-adhesive composite patch for wound repair of extraction sockets according to claim 4, wherein in the step (S2), the electrospinning conditions are as follows: the external high voltage is 10-20 kV, the receiving distance is 13-15 cm, and the liquid inlet speed is 0.8-1.0 mL/h.
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| CN109513046A (en) * | 2018-12-18 | 2019-03-26 | 诺迈尔（苏州）医学科技有限公司 | A kind of absorbable oral restoration film and preparation method thereof |
| CN214231722U (en) * | 2020-12-14 | 2021-09-21 | 江苏省苏北人民医院 | Dental postoperative hemostatic piece |
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2021
- 2021-12-23 CN CN202111587261.4A patent/CN114306718A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN103736153A (en) * | 2013-12-30 | 2014-04-23 | 北京市创伤骨科研究所 | Single-layer and double-layer polycaprolactone-based guided tissue regeneration membranes and preparation method thereof |
| US20150273119A1 (en) * | 2014-03-26 | 2015-10-01 | Snu R&Db Foundation | Formulation comprising anti-scarring agents and biocompatible polymers for medical device coating |
| JP2015189710A (en) * | 2014-03-28 | 2015-11-02 | 国立研究開発法人国立長寿医療研究センター | implant body |
| CN105688274A (en) * | 2016-01-20 | 2016-06-22 | 江苏省人民医院 | Preparation technology of PCL/GE (polycaprolactone/gelatin) electrospinning composite stent |
| CN109513046A (en) * | 2018-12-18 | 2019-03-26 | 诺迈尔（苏州）医学科技有限公司 | A kind of absorbable oral restoration film and preparation method thereof |
| CN214231722U (en) * | 2020-12-14 | 2021-09-21 | 江苏省苏北人民医院 | Dental postoperative hemostatic piece |
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