Preparation method of medicine-carrying plugging treatment device based on digital photocuring 3D printing technology

Abstract

The invention relates to the field of biological medicine, and discloses a preparation method of a medicine-carrying plugging treatment device based on a digital photocuring 3D printing technology, which comprises the following steps: step 1, importing an initial structure of the plugging treatment device based on oral cavity three-dimensional scanning data into three-dimensional design software, dividing a space region of the initial structure of the plugging treatment device into a plurality of discrete points, and forming a plurality of discrete points; constructing a Thiessen polygonal porous structure based on the discrete points; 2, converting the Thiessen polygonal porous structure into a slice file adaptive to photocuring 3D printing, and importing the slice file into a photocuring 3D printer for layer-by-layer printing to obtain a porous plugging device blank; and step 3, cleaning the porous plugging treatment device green bodies in sequence. Personalized modeling based on oral cavity three-dimensional scanning data, parameterized topological optimization of a Thiessen polygonal porous structure and a digital photocuring 3D printing technology are fused, and pore filling of drug-loaded hydrogel is combined, so that personalized fitting of the plugging treatment device, an alveolar ridge and periodontal tissue is achieved.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of biological medicine, in particular to a drug-loaded plug appliance preparation method based on digital light-cured 3D printing technology. BACKGROUND

[0002] In the field of biological medicine, in the clinical treatment of oral diseases (such as periodontitis and dry socket), the plug appliance as an important auxiliary instrument is mainly used for isolating the wound surface, protecting the tissue and reducing external stimulation, so as to promote the healing of the wound surface. The additive manufacturing (3D printing) technology has become one of the core technologies for the preparation of personalized medical devices due to its advantages of not requiring a mold and being capable of directly manufacturing a complex three-dimensional structure. The digital light-cured 3D printing technology is widely used in the preparation of oral prosthetic instruments due to its characteristics of micron-level forming precision, easy regulation of material biocompatibility and strong realizability of complex topological structures, and provides technical support for the personalized design and function integration of the plug appliance.

[0003] Traditional plug appliances are mostly prepared in a solid structure by using mold pressing or mechanical processing technology, and the preparation process relies on a preformed mold, so that the plug appliance has poor fitting with the alveolar ridge and periodontal tissue and cannot meet the long-term local treatment requirements. SUMMARY

[0004] In view of the deficiencies of the prior art, the application provides a drug-loaded plug appliance preparation method based on digital light-cured 3D printing technology, which solves the problem that the traditional plug appliance relies on a preformed mold in the preparation process, has poor fitting with the alveolar ridge and periodontal tissue and cannot meet the long-term local treatment requirements.

[0005] To achieve the above object, the application is implemented by the following technical scheme: a drug-loaded plug appliance preparation method based on digital light-cured 3D printing technology, comprising the following steps: Step 1: importing a plug appliance initial structure based on oral three-dimensional scanning data into a three-dimensional design software, dividing the space region of the plug appliance initial structure into a plurality of discrete points, and constructing a Voronoi polygon porous structure based on the discrete points; Step 2: converting the Voronoi polygon porous structure into a slice file suitable for light-cured 3D printing, importing the slice file into a light-cured 3D printer for layer-by-layer printing, and obtaining a porous plug appliance blank; Step 3: sequentially performing cleaning, secondary solidification and drying treatment on the porous plug appliance blank, and obtaining a formed porous plug appliance; Step 4: immersing the formed porous plug appliance in a drug-loaded hydrogel, so that the drug-loaded hydrogel fills the pores of the formed porous plug appliance, and obtaining a drug-loaded plug appliance.

[0006] By adopting the technical scheme, through the fusion of the personalized modeling based on the oral cavity three-dimensional scanning data, the parametric topological optimization of the Voronoi polygon porous structure and the digital light curing 3D printing technology, combined with the pore filling of the drug-loaded hydrogel, the personalized fitting of the plugger and the alveolar ridge and periodontal tissue is realized, and through the drug loading and slow release of the porous structure, the preparation of the drug-loaded plugger with personalized adaptability and long-term local treatment function is realized, and the problem that the traditional plugger depends on the prefabricated mold in the preparation process, so that the fitting with the alveolar ridge and periodontal tissue is poor, and the long-term local treatment demand cannot be met.

[0007] Preferably, in step one, the number of discrete points is 2000-5000.

[0008] Preferably, in step one, in the Voronoi polygon porous structure, the diameter of the rod constituting the polygon is 0.245mm-0.329mm.

[0009] Preferably, in step one, the porosity of the Voronoi polygon porous structure is 60%, and the porosity is controlled by adjusting the number of discrete points and the diameter of the rod.

[0010] Preferably, in step two, the layer thickness of the slice file is 0.05mm, and the biocompatible photosensitive resin is used for layer-by-layer printing.

[0011] Preferably, in step two, the exposure time of the first layer of the light curing 3D printing is 60s, the exposure time of the non-first layer is 6s, and the ultraviolet light wavelength is 365-405nm.

[0012] Preferably, in step three, the cleaning is ultrasonic cleaning of the porous plugger blank in anhydrous ethanol, and the cleaning time is 5-10min.

[0013] Preferably, in step three, the secondary curing is to place the cleaned porous plugger blank in an ultraviolet curing box for curing treatment with an ultraviolet light intensity of 20mW / cm² and a treatment time of 10-15min.

[0014] Preferably, in step three, the drying is to place the secondary cured porous plugger blank in a vacuum drying box for drying treatment at a drying temperature of 38-60℃ and a drying time of 2-4h.

[0015] Preferably, in step four, the immersion time is 10-15min, and the excess drug-loaded hydrogel on the surface of the formed porous plugger is removed after immersion.

[0016] The application provides a drug-loaded plugger preparation method based on digital light curing 3D printing technology. 1. The application realizes the personalized fitting of the plugger and the alveolar ridge and periodontal tissue by fusing the personalized modeling based on the three-dimensional scanning data of the oral cavity, the parametric topological optimization of the Voronoi polygon porous structure and the digital light-cured 3D printing technology, and filling the pores of the drug-loaded hydrogel, and realizes the preparation of the drug-loaded plugger with personalized adaptability and long-term local treatment function by drug loading and slow release of the porous structure, solves the problem that the traditional plugger relies on the prefabricated mold in the preparation process, resulting in poor fitting with the alveolar ridge and periodontal tissue, and cannot meet the long-term local treatment demand.

[0017] 2. The application realizes the parametric regulation of the Voronoi polygon porous structure, controls the porosity stably, and cooperates with the rod diameter and the number of discrete points to ensure that the structure has sufficient support strength to withstand the mastication force in the oral cavity, while reducing the weight of the instrument, and improves the wearing comfort and long-term use compliance of the patient.

[0018] 3. The connected pore network formed by the Voronoi polygon porous structure provides sufficient and uniform filling space for the drug-loaded hydrogel, and the cooperation of the porous structure and the hydrogel can delay the drug release rate, avoid the situation of initial burst release and insufficient release in the later period, and provide a reliable delivery platform for long-term local drug treatment of periodontitis, dry socket and other diseases. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 The plugger design drawing of the Voronoi polygon topological structure of the application; Figure 2 The plugger design drawing of the Voronoi polygon topological structure of the application; Figure 3 The plugger design drawing of the Voronoi polygon topological structure of the application; Figure 4 The plugger design drawing of the Voronoi polygon topological structure of the application; DETAILED DESCRIPTION

[0020] The technical solutions of the application will be described clearly and completely below with reference to the drawings of the application. Obviously, the described embodiments are only part of the embodiments of the application, not all. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative labor belong to the scope of protection of the application.

[0021] Please refer to the drawings of the application Figure 1 - the drawings of the application Figure 4 The application embodiment provides a drug-loaded plugger preparation method based on digital light-cured 3D printing technology, which comprises the following steps: Step one: import the initial structure of the occlusal guard based on the three-dimensional scanning data of the oral cavity into the three-dimensional design software, divide the spatial region of the initial structure of the occlusal guard into a plurality of discrete points, and construct a Voronoi polygon porous structure based on the discrete points; Further, in step one, the number of discrete points is 2000-5000.

[0022] Further, in step one, in the Voronoi polygon porous structure, the diameter of the rod constituting the polygon is 0.245-0.329 mm.

[0023] Further, in step one, the porosity of the Voronoi polygon porous structure is 60%, and the porosity is controlled by adjusting the number of discrete points and the diameter of the rod.

[0024] Specifically, step one converts the initial structure of the occlusal guard based on the anatomical features of the patient's oral cavity into a Voronoi polygon porous structure with personalized adaptability and drug loading function through parametric topological optimization design, laying a structural foundation for subsequent light-cured 3D printing and drug loading.

[0025] Generally, first, the three-dimensional scanning data of the patient's oral cavity is obtained, which is usually collected by oral cone beam computed tomography or intraoral scanning equipment, and can reflect the morphological features of the patient's alveolar ridge and periodontal tissue and other oral anatomical structures. The initial structure of the occlusal guard reconstructed based on this scanning data can ensure that the final prepared occlusal guard has good fit with the patient's oral tissue and meets the needs of personalized treatment.

[0026] The above-mentioned initial structure of the occlusal guard is imported into the three-dimensional design software. In the three-dimensional design software, first, the spatial region of the initial structure of the occlusal guard needs to be discretized, that is, a plurality of discrete points are divided. The uniformity of the distribution of the discrete points will affect the uniformity and stability of the Voronoi polygon porous structure constructed subsequently, and generally needs to be set according to the size and morphological features of the occlusal guard. In some embodiments, the number of discrete points is 2000-5000. As an option, for a smaller anterior tooth area occlusal guard, 2000-3000 discrete points can be selected; for a larger posterior tooth area occlusal guard, 3000-5000 discrete points can be selected to adapt to the structural requirements of different areas.

[0027] After the discrete points are divided, a Voronoi polygon porous structure is constructed based on these discrete points. The Voronoi polygon structure is a Voronoi diagram generated based on a set of discrete points, which is characterized by containing only one discrete point in each polygon, and the edge of the polygon is the perpendicular bisector of the connecting line of the two adjacent discrete points, which can form a uniform and connected porous network, which is conducive to the penetration and filling of the subsequent drug carrier.

[0028] The diameter of the rods that make up the Thiessen polygons ranges from 0.245mm to 0.329mm. Rod diameter is a parameter that influences the mechanical properties of the structure. In one possible implementation, a rod diameter of 0.300mm to 0.329mm can be selected for the edge of the plug, which requires higher support strength. For the internal area primarily used for drug loading, a rod diameter of 0.245mm to 0.280mm can be selected to maximize drug loading space while ensuring overall strength.

[0029] Generally, the porosity of a Thiessen polygon porous structure must be controlled at 60%, ensuring the structure has sufficient strength to meet the needs of oral clinical use while providing ample space for drug carriers. The porosity is primarily controlled by synergistically adjusting the number of discrete points and the rod diameter. Specifically, as the number of discrete points increases, the rod diameter must be appropriately reduced to maintain a 60% porosity; as the number of discrete points decreases, the rod diameter must be appropriately increased.

[0030] As an option, in the process of constructing the Thiessen polygon porous structure, the mechanical properties of the structure can be pre-evaluated through the simulation function of the three-dimensional design software, such as simulating the structural deformation under the pressure of oral chewing. If it is found that the strength of a local area is insufficient, it can be optimized by increasing the number of discrete points in the area or appropriately increasing the rod diameter of the corresponding area to ensure the reliability of the structure. The constructed Thiessen polygon porous structure must be consistent with the edge contour of the initial structure of the plug to ensure that the product can fit the patient's oral tissue.

[0031] In some embodiments, after constructing the Thiessen polygon porous structure, the structure can also be locally refined. For example, the diameter of the rod can be appropriately reduced in the area in contact with the gums to increase softness and improve wearing comfort, while the diameter of the rod can be appropriately increased in the area that needs to withstand greater bite force to enhance strength, so that the plug can achieve a balance between function and comfort.

[0032] Step 2: Convert the Voronoi polygon porous structure into a slice file suitable for light-curing 3D printing, import the slice file into the light-curing 3D printer for layer-by-layer printing, and obtain a porous plug blank; Furthermore, in step 2, the layer thickness of the slice file is 0.05 mm, and biocompatible photosensitive resin is used for layer-by-layer printing.

[0033] Furthermore, in step 2, the exposure time of the first layer of the light-curing 3D printing is 60 seconds, the exposure time of the non-first layer is 6 seconds, and the wavelength of the ultraviolet light is 365-405 nm.

[0034] Specifically, step two is to convert the Voronoi polygon porous structure constructed in step one into processing instructions that can be recognized by a light-curable 3D printer, and by precisely controlling the printing parameters, the biocompatible photosensitive resin is used to solidify layer by layer to obtain a pre-set porous structure of the plugger blank, providing a basic entity for subsequent post-processing and drug loading process.

[0035] The constructed Voronoi polygon porous structure model is exported in a general three-dimensional model format for import into slicing software for processing. After importing the Voronoi polygon porous structure model into the slicing software, slicing processing is required to generate a slicing file suitable for light-curable 3D printing. The slicing process cuts the three-dimensional model layer by layer along the height direction, and each layer corresponds to one forming operation of the printer. The slicing file contains the contour information and printing parameters of each layer.

[0036] In some embodiments, the layer thickness of the slicing file is set to 0.05 mm. The diameter of the rods in the Voronoi polygon porous structure is relatively small, usually between 0.245 mm and 0.329 mm, and a smaller layer thickness can better restore the cylindricality and structural details of the rods.

[0037] After generating the slicing file, it is imported into the light-curable 3D printer. Generally, biocompatible photosensitive resin is used for layer-by-layer printing. It needs to meet the biological safety requirements for use in the oral cavity and can be quickly solidified under ultraviolet light, as an option, the biocompatible photosensitive resin can be selected from acrylate resins.

[0038] In one possible implementation, the light-curable 3D printing process, the ultraviolet light wavelength is set to 365-405 nm, which can excite the photoinitiator in the resin to promote rapid crosslinking and solidification of the resin monomer. In some embodiments, the first layer exposure time is 60 s, which ensures that the resin and the forming platform of the printer can be firmly combined to avoid the whole structure from falling off due to the self-weight or solidification shrinkage during the subsequent printing process; the non-first layer exposure time is 6 s, which can ensure sufficient solidification and reduce material shrinkage and energy consumption, improving printing efficiency.

[0039] As an option, during the printing process, a sufficient amount of biocompatible photosensitive resin needs to be pre-injected into the tank of the printer to ensure that there is enough resin for solidification and formation during each layer printing. After the printing starts, the ultraviolet light irradiates the corresponding area according to the contour information of the slicing file, causing the resin in that area to solidify and form a layer of structure; then, the forming platform rises by a certain height (i.e. layer thickness), new resin flows into the area to be printed, and the above process is repeated until the entire porous plugger blank is printed.

[0040] Through the above slicing processing and printing, the reduction of the tessellation porous structure can be ensured, and the printed porous plug appliance blank has both the porosity and the rod diameter consistent with the design and good structural integrity, thereby providing a reliable entity basis for subsequent post-processing and drug loading.

[0041] Step three: sequentially performing cleaning, secondary curing and drying treatment on the porous plug appliance blank to obtain a formed porous plug appliance; Further, in step three, the cleaning is ultrasonic cleaning of the porous plug appliance blank in anhydrous ethanol, and the cleaning time is 5-10 min.

[0042] Further, in step three, the secondary curing is curing treatment of the cleaned porous plug appliance blank in a UV curing box with a UV light intensity of 20 mW / cm² and a treatment time of 10-15 min.

[0043] Further, in step three, the drying is drying treatment of the secondarily cured porous plug appliance blank in a vacuum drying box at a drying temperature of 38-60°C and a drying time of 2-4 h.

[0044] Specifically, step three removes impurities remaining in the printing process, enhances the cross-linking degree of the material, and removes excess moisture by post-processing of the porous plug appliance blank, thereby obtaining a formed porous plug appliance with stable structure and reliable performance, and providing a qualified substrate for subsequent drug loading.

[0045] Generally, the surface and internal pores of the printed porous plug appliance blank will have residual uncured photosensitive resin, and the porous plug appliance blank needs to be cleaned. Specifically, the cleaning operation adopts the method of placing the porous plug appliance blank in anhydrous ethanol for ultrasonic cleaning. The ultrasonic cleaning method can use the vibration effect of ultrasonic waves to promote ethanol to penetrate into the fine pores of the porous structure, more thoroughly dissolve and remove the residual uncured resin.

[0046] The cleaned porous plug appliance blank has removed the surface residues, but the cross-linking degree of the resin may not have reached the optimal state, and therefore, the next secondary curing treatment is needed. Generally, the secondary curing is performed in a UV curing box. Through the re-irradiation of ultraviolet light, the resin molecules are further cross-linked, thereby enhancing the structural strength and stability of the plug appliance and reducing the risk of deformation or fracture during use. Specifically, the secondary curing parameter is set to a UV light intensity of 20 mW / cm² and a treatment time of 10-15 min. During secondary curing, the porous plug appliance blank can be uniformly placed to avoid mutual stacking and ensure the consistency of curing.

[0047] After the secondary solidification is completed, a small amount of ethanol brought in during the cleaning process and a trace amount of moisture generated by the solidification reaction may remain in the porous plug appliance blank, and drying treatment is needed to remove these liquids. Specifically, the drying operation is performed on the porous plug appliance blank after secondary solidification in a vacuum drying box. The reason for using a vacuum drying box is that a vacuum environment can lower the boiling point of the liquid, accelerate the volatilization of ethanol and moisture, and at the same time avoid the pollution of impurities in the air to the plug appliance. In some embodiments, the drying temperature is set to 38-60°C, and the drying time is 2-4h. To ensure that the moisture is fully removed.

[0048] Through the sequential treatment of cleaning, secondary solidification and drying, the performance of the porous plug appliance blank is optimized, potential contaminants are removed, and the structural stability is improved, laying a solid foundation for the subsequent effective combination with the drug-loaded hydrogel.

[0049] Step four: immerse the shaped porous plug appliance in the drug-loaded hydrogel, so that the drug-loaded hydrogel fills the pores of the shaped porous plug appliance, and obtain the drug-loaded plug appliance.

[0050] Further, in step four, the immersion time is 10-15min, and after immersion, the excess drug-loaded hydrogel on the surface of the shaped porous plug appliance is removed.

[0051] Specifically, step four utilizes the porous structure characteristics of the shaped porous plug appliance to realize the combination of the drug-loaded hydrogel and the structure through immersion, so that the drug carrier is uniformly filled into the pores, and a plug appliance with drug loading function is obtained, providing a drug delivery platform for oral local treatment.

[0052] The drug-loaded hydrogel needs to be selected from medical-grade hydrogels with good biocompatibility, fluidity and drug compatibility. Such hydrogels not only can stably load drugs (such as antibacterial drugs, anti-inflammatory drugs, etc.), but also can adapt to the humid environment in the oral cavity, avoiding the premature release of drugs due to rapid degradation.

[0053] When the shaped porous plug appliance is immersed in the drug-loaded hydrogel, the capillary action and pore connectivity of the porous structure promote the penetration of the hydrogel. The pores inside the shaped porous plug appliance provide accommodation space and penetration channels for the hydrogel, so that the hydrogel can gradually diffuse from the surface to the inside. In some embodiments, the immersion time is set to 10-15min. After immersion is completed, the excess drug-loaded hydrogel on the surface of the shaped porous plug appliance needs to be removed, which can be removed by gently wiping the surface with sterile filter paper. The operation needs to be gentle to avoid damaging the hydrogel that has been filled into the pores.

[0054] Through the above impregnation and surface treatment, the drug-loaded hydrogel can be stably filled in the pores of the shaped porous plug appliance, forming a drug-loaded plug appliance integrated with the structure-drug carrier, which not only retains good adhesion to the oral tissue, but also realizes slow release of the drug through the hydrogel in the pores, meeting the demand of drug delivery for oral local treatment.

[0055] Through the fusion of personalized modeling based on oral three-dimensional scanning data, parameterized topological optimization of the tessellation polygon porous structure, and digital light curing 3D printing technology, combined with the pore filling of drug-loaded hydrogel, the personalized adhesion of the plug appliance to the alveolar ridge and periodontal tissue is realized, and the preparation of the drug-loaded plug appliance with personalized adaptability and long-term local treatment function is realized through the drug loading and slow release of the porous structure, solving the problem that the traditional plug appliance relies on a pre-made mold in the preparation process, resulting in poor adhesion to the alveolar ridge and periodontal tissue, and failing to meet the long-term local treatment needs.

[0056] The following will be further described in conjunction with specific embodiments: Example 1

[0057] The drug-loaded plug appliance preparation method based on digital light curing 3D printing technology has the following specific steps: (1) A computer-aided design (CAD) software is used to construct a plug appliance three-dimensional model, and a parameterized topological optimization algorithm is used to convert a traditional solid cylindrical structure into a biomimetic tessellation polygon porous structure, referring to Figure 1 a. By adjusting the number of discrete points (2000), the porosity (60%), and the diameter of the rod (0.329 mm), the mechanical properties of the structure are optimized.

[0058] (2) A biocompatible photosensitive resin is selected as the base material, the design model is imported into a high-precision digital light curing 3D printer, and the printing parameters are set as follows: ultraviolet light wavelength 405 nm, light intensity 3800 μW / cm², single-layer exposure time 8 s, and layer thickness 50 μm. The appliance is formed by layer-by-layer curing, referring to Figure 2 a. After printing, ethanol ultrasonic cleaning (10 min), secondary curing (ultraviolet light intensity 20 mW / cm², 15 min), and 38°C vacuum drying treatment are performed in sequence.

[0059] (3) The shaped and post-processed porous plug appliance is immersed in hydrogel, and the hydrogel is used as a model drug to simulate the actual drug loading process, referring to Figure 3 a. It can be seen that the porous structure can absorb and contain hydrogel, indicating that it has drug loading potential. Example 2

[0060] The drug-loaded plug appliance preparation method based on digital light curing 3D printing technology has the following specific steps: (1) Construct the three-dimensional model of the plug by computer-aided design (CAD) software, and convert the traditional solid cylindrical structure into a biomimetic tessellation polygonal porous structure by a parameterized topological optimization algorithm, refer to Figure 1 b. By adjusting the number of discrete points (3000), porosity (60%) and the diameter of the rod (0.289 mm), the mechanical properties of the structure are optimized.

[0061] (2) Select biocompatible photosensitive resin as the matrix material, import the design model into a high-precision digital light-cured 3D printer, and set the printing parameters as follows: ultraviolet light wavelength 405 nm, light intensity 3800 μW / cm², single-layer exposure time 8 s, and layer thickness 50 μm. The instrument is formed by layer-by-layer curing, refer to Figure 2 b. After printing, sequentially perform ethanol ultrasonic cleaning (10 min), secondary curing (ultraviolet light intensity 20 mW / cm², 15 min) and 38°C vacuum drying treatment.

[0062] (3) Immerse the formed and post-processed porous plug in the hydrogel, use the hydrogel as the model drug to simulate the actual drug loading process, refer to Figure 3 b. It can be seen that the porous structure can absorb and accommodate the hydrogel, which indicates that it has drug loading potential. Example 3

[0063] The drug-loaded plug preparation method based on digital light-cured 3D printing technology has the following specific steps: (1) Construct the three-dimensional model of the plug by computer-aided design (CAD) software, and convert the traditional solid cylindrical structure into a biomimetic tessellation polygonal porous structure by a parameterized topological optimization algorithm, refer to Figure 1 c. By adjusting the number of discrete points (4000), porosity (60%) and the diameter of the rod (0.263 mm), the mechanical properties of the structure are optimized.

[0064] (2) Select biocompatible photosensitive resin as the matrix material, import the design model into a high-precision digital light-cured 3D printer, and set the printing parameters as follows: ultraviolet light wavelength 405 nm, light intensity 3800 μW / cm², single-layer exposure time 8 s, and layer thickness 50 μm. The instrument is formed by layer-by-layer curing, refer to Figure 2 c. After printing, sequentially perform ethanol ultrasonic cleaning (10 min), secondary curing (ultraviolet light intensity 20 mW / cm², 15 min) and 38°C vacuum drying treatment.

[0065] (3) Immerse the formed and post-processed porous plug in the hydrogel, use the hydrogel as the model drug to simulate the actual drug loading process, refer to Figure 3c.It can be seen that the porous structure can absorb and accommodate hydrogel, which can indicate its drug loading potential. Example 4

[0066] The drug-loaded plug appliance preparation method based on digital light-cured 3D printing technology comprises the following specific steps: (1) A computer-aided design (CAD) software is used to construct a plug appliance three-dimensional model, a parametric topological optimization algorithm is used to convert a traditional solid cylindrical structure into a biomimetic tessellation polygon porous structure, and a reference is made to Figure 1 d. The mechanical properties of the structure are optimized by adjusting the number of discrete points (5000), the porosity (60%) and the diameter of the rod (0.245 mm).

[0067] (2) A biocompatible photosensitive resin is selected as a base material, the design model is imported into a high-precision digital light-cured 3D printer, and the printing parameters are set as follows: the ultraviolet light wavelength is 405 nm, the light intensity is 3800 μW / cm², the single-layer exposure time is 8 s, and the layer thickness is 50 μm. The appliance is formed by layer-by-layer curing, and a reference is made to Figure 2 d. After printing, ethanol ultrasonic cleaning (10 min), secondary curing (ultraviolet light intensity 20 mW / cm², 15 min) and 38℃ vacuum drying treatment are sequentially performed.

[0068] (3) The formed and post-processed porous plug appliance is immersed in hydrogel, and the hydrogel is used as a model drug to simulate the actual drug loading process, and a reference is made to Figure 3 d. It can be seen that the porous structure can absorb and accommodate hydrogel, which can indicate its drug loading potential.

[0069] As can be seen from the above, the present application uses design and manufacturing technology (topological optimization + 3D printing) to develop a new type of functional (drug-loaded) medical appliance, and provides an ideal carrier platform for drug loading.

[0070] Although embodiments of the present application have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made therein without departing from the principles and spirit of the present application, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for preparing a drug-loaded plug appliance based on digital light solidification 3D printing technology, characterized in that, The method comprises the following steps: Step 1: importing the initial structure of the plugger based on the three-dimensional scanning data of the oral cavity into a three-dimensional design software, dividing the space region of the initial structure of the plugger into a plurality of discrete points, and constructing a Voronoi polygon porous structure based on the discrete points; Step 2: converting the Voronoi polygon porous structure into a slice file suitable for light-cured 3D printing, importing the slice file into a light-cured 3D printer for layer-by-layer printing to obtain a porous plugger blank; Step 3: sequentially performing cleaning, secondary curing and drying treatment on the porous plugger blank to obtain a formed porous plugger; Step 4: immersing the formed porous plugger in a drug-loaded hydrogel to fill the drug-loaded hydrogel into the pores of the formed porous plugger to obtain a drug-loaded plugger.

2. The method of claim 1, wherein the method is a method of fabricating a drug- loaded insert appliance based on digital light processing (DLP) 3D printing technology. In step 1, the number of discrete points is 2000-5000.

3. The method of claim 1, wherein the method is a method of fabricating a drug- loaded insert appliance based on digital light processing (DLP) 3D printing technology. In step 1, the diameter of the rod constituting the polygon in the Voronoi polygon porous structure is 0.245-0.329 mm.

4. The method of claim 1, wherein the method is a method of fabricating a drug- loaded insert appliance based on digital light processing (DLP) 3D printing technology. In step 1, the porosity of the Voronoi polygon porous structure is 60%, and the porosity is controlled by adjusting the number of discrete points and the diameter of the rod.

5. The method of claim 1, wherein the method is a method of fabricating a drug- loaded insert appliance based on digital light processing (DLP) 3D printing technology. In step 2, the layer thickness of the slice file is 0.05 mm, and the layer-by-layer printing is performed using biocompatible photosensitive resin.

6. The method of claim 1, wherein the method is a method of fabricating a drug- loaded insert appliance based on digital light processing (DLP) 3D printing technology. In step 2, the first layer exposure time of the light-cured 3D printing is 60 s, the non-first layer exposure time is 6 s, and the ultraviolet light wavelength is 365-405 nm.

7. The method of claim 1, wherein the method is a method of fabricating a drug- loaded insert appliance based on digital light processing (DLP) 3D printing technology. In step 3, the cleaning is ultrasonic cleaning of the porous plugger blank in anhydrous ethanol, and the cleaning time is 5-10 min.

8. The method of claim 1, wherein the method is a method of fabricating a drug- loaded insert appliance based on digital light processing (DLP) 3D printing technology. In step 3, the secondary curing is placing the cleaned porous plugger blank in an ultraviolet curing box for curing treatment with an ultraviolet light intensity of 20 mW / cm2 and a treatment time of 10-15 min.

9. The method of claim 1, wherein the method is a method of fabricating a drug- loaded insert appliance based on digital light processing (DLP) 3D printing technology. In step 3, the drying is placing the secondary-cured porous plugger blank in a vacuum drying box for drying treatment at a drying temperature of 38-60°C and a drying time of 2-4 h.

10. The method of claim 1, wherein the method is a method of fabricating a drug- loaded insert appliance based on digital light processing (DLP) 3D printing technology. In step 4, the immersion time is 10-15 min, and the excess drug-loaded hydrogel on the surface of the formed porous plugger is removed after immersion.

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