Bionic rhizome structure biological ceramic scaffold for bone increment

Abstract

The invention provides a bionic rhizome structure biological ceramic scaffold for bone increment, which is characterized in that the whole scaffold is of a bionic rhizome structure, specifically, the upper structure of the scaffold is of a trunk-imitating conduit structure, the lower structure of the scaffold is of a rhizome-imitating bionic bone trabecula porous structure, and the periphery of the scaffold is wrapped by a solid side wall structure. The upper structure is composed of a conical channel, the capillary effect of the channel is beneficial to retention of blood, the upper limit capable of achieving increment height is increased, and the conical channel has the advantages of being good in biocompatibility, high in mechanical strength, low in clinical technology sensitivity and the like.

Description

Technical Field

[0001] The present application relates to the field of bone grafting materials used for bone augmentation in dental implants, and specifically to a 3D printed bioceramic scaffold used for bone augmentation. Background Art

[0002] After tooth loss, implant restoration has gradually become the preferred restoration option for patients due to its advantages such as good comfort, excellent functional restoration and no damage to the health of other teeth. It is regarded as one of the conventional restoration methods for tooth loss. However, due to certain factors such as severe inflammation, infection, trauma, tumors or long-term tooth loss, the bone mass at the implant site may be insufficient. In order to ensure that the implant can obtain the ideal initial stability and maintain the long-term restoration effect, sufficient bone mass and high-quality bone are indispensable. The loss of bone mass not only affects the scope of indications for implant treatment, but is also directly related to the quality, functional load, aesthetic effect and long-term survival time of the implant in the mouth. Therefore, solving the problem of insufficient bone mass is crucial to improving the success rate of implant restoration.

[0003] Bone augmentation faces unique challenges, such as lack of support from the surrounding bone wall, poor blood supply, connective tissue infiltration, etc. Currently, bone augmentation is mainly performed through surgical methods such as ONLAY bone grafting and GBR combined with bone grafting materials. However, traditional bone grafting materials used for bone augmentation, such as autologous bone and xenogeneic bone implant materials, still have various limitations. Specifically:

[0004] GBR is one of the most commonly used and effective bone augmentation techniques in clinical practice. However, the granular bone substitute material used in the surgery is difficult to shape, easy to shift, and difficult to obtain good support. Therefore, it needs to be combined with a rigid stent or tent nail technology to ensure the expected therapeutic effect.

[0005] Autologous bone grafts are considered the gold standard for bone tissue engineering due to their osteoconductive, osteoinductive, and osteogenic potentials, and they can restore blood supply most quickly, however, autologous bone grafts have a rapid and unpredictable bone resorption pattern. Other issues with the use of autologous grafts include limited supply, invasive surgery, possible donor site morbidity, and postoperative complications;

[0006] The most classic product currently used for xenogeneic bone transplantation is Bio-Oss bone powder, but it is difficult to shape, easy to shift, and difficult to obtain good support;

[0007] 3D printed titanium mesh is gradually being used in bone augmentation due to its good mechanical properties and the ability to accurately control the three-dimensional contour and volume of guided bone regeneration. However, 3D printed titanium mesh can only provide spatial maintenance capabilities and has no bone inductivity. It also has defects such as immune rejection and titanium mesh exposure, and requires a secondary clinical surgery to remove it.

[0008] Therefore, it is imperative to develop bone implant materials that can stably provide spatial support for the bone augmentation area while reducing clinical technical sensitivity and achieving efficient and high-quality augmentation.

[0009] With the continuous development of 3D printing technology and biomaterials, 3D printed bioceramic scaffolds have shown great potential in bone augmentation. Among them, 3D printing technology can realize the innovative design of complex structures, and can be customized according to the specific bone defect conditions of the patient to achieve individualized treatment. Bioceramics can ensure good biocompatibility while providing excellent osteoconduction / osteoinduction properties and space maintenance capabilities. Unfortunately, the structural design and application research of 3D printed bioceramic scaffolds used for bone augmentation is still lacking. Therefore, this application is committed to developing a new type of 3D printed bioceramic scaffold structure to achieve efficient and stable bone augmentation effects. Summary of the invention

[0010] The present invention is committed to developing a novel structure of 3D printed bioceramic scaffold, which satisfies the conditions required for bone augmentation, including early blood supply reconstruction, space maintenance, bone induction, etc., to achieve efficient and stable bone augmentation effect.

[0011] Inspired by the efficient water absorption capacity and stable maintenance of tree roots, the present invention provides a bionic rhizome structured bioceramic scaffold for bone augmentation, characterized in that the overall configuration of the scaffold is a bionic rhizome structure, specifically, its upper structure is a duct structure that simulates a tree trunk, and its lower structure is a bionic trabecular porous structure that simulates a rhizome, and the periphery of the scaffold is wrapped by a solid sidewall structure.

[0012] The conduit structure is a conical channel structure, which is composed of a hexagonal cone channel, and the aperture at the top is larger than the aperture at the bottom.

[0013] Preferably, the upper aperture is 700um, and the lower aperture is 300um. The shape can also be designed to be other shapes such as circle, octagon, etc. The aperture or side length is determined by the area of ​​the bone defect.

[0014] Preferably, the edge of the support is a solid side wall 200-300um thick.

[0015] The present application provides a method for manufacturing a bionic rhizome structure bioceramic scaffold for bone augmentation, specifically:

[0016] Design a three-dimensional digital model of the bioceramic scaffold according to the size range of the defect and the required incremental height;

[0017] Bioceramic scaffolds were prepared using 3D printing equipment under a λ=405nm ultraviolet light source; the photosensitive ceramic-resin composite material was composed of HA / TCP (3:7); the thickness of each slice layer in DLP was set to 30μm, and the exposure time was 5 seconds;

[0018] After printing, the scaffold was separated from the support plate and thoroughly washed with sufficient distilled water to remove the remaining liquid slurry. The sample was then heated to 600°C at a heating rate of 2°C / min and kept warm for 120 min. Subsequently, it was further heated to 1100°C at a heating rate of 1°C / min and kept warm for another 120 min to obtain a sintered bioceramic scaffold with a shrinkage rate of approximately 22%.

[0019] Beneficial effects:

[0020] The present invention is inspired by the excellent water absorption capacity of the root structure during the growth of the tree, and designs a bioceramic scaffold with a biomimetic root structure. The lower structure of the scaffold is a loose and porous trabecular bone structure, which can absorb blood through capillary action. The capillary action of the upper channel helps to retain blood, increase the upper limit of the incremental height that can be achieved, and has the advantages of good biocompatibility, high mechanical strength and low clinical technical sensitivity. Compared with autologous bone blocks, the raw materials of the scaffold are derived from inorganic substances, are extremely easy to obtain, and avoid rapid absorption. Compared with granular bone substitute materials such as bioss bone powder, the scaffold can be directly implanted into the defect area through printing, and provides stable space maintenance ability and is easy to operate, with low clinical technical sensitivity. Compared with 3D printed titanium mesh scaffolds, the scaffold can provide bone induction ability, avoid secondary removal after surgery, and reduce patient pain. In summary, the present invention can avoid the defects of existing bone implant materials for bone augmentation, and at the same time can achieve stable, efficient and high-quality bone augmentation. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 The overall cross-sectional schematic diagram of the bionic rhizome structure bioceramic scaffold used for bone augmentation;

[0022] Figure 2 Schematic diagram of the porous structure of the lower bionic trabecular bone;

[0023] Figure 3 It is a schematic diagram of the cross section of the upper tapered channel structure;

[0024] Figure 4 A top view of a bionic rhizome structured bioceramic scaffold for bone augmentation;

[0025] Figure 5 The blood absorption experimental effect of the bioceramic scaffold of the present invention;

[0026] Figure 6 The results of the angiogenesis ability test;

[0027] Figure 7 The results of the osteogenic capacity test;

[0028] Figure 8These are the animal validation test results of the bioceramic scaffold of the present invention. DETAILED DESCRIPTION

[0029] A bionic rhizome structure bioceramic scaffold for bone augmentation, characterized in that the overall configuration of the scaffold is a bionic rhizome structure. Specifically, the lower structure corresponds to the loose porous medium in the roots for absorbing water and is designed as a porous structure of bionic trabeculae, and the upper structure corresponds to the channel in the trunk and is designed as a conical channel structure.

[0030] The conical channel structure is composed of a hexagonal cone channel, with an upper aperture of 600-800um and a lower aperture of 200-300um. The shape can also be designed to be other shapes such as circle, octagon, etc. The aperture or side length is determined by the area of ​​the bone defect.

[0031] The edge of the bracket is a solid side wall with a width of 200-300um.

[0032] The present application provides a method for preparing a bionic rhizome structure bioceramic scaffold for bone augmentation, specifically:

[0033] According to the size range of the defect and the required incremental height, a three-dimensional digital model of the bioceramic scaffold is designed; the bioceramic scaffold is prepared under a λ=405nm ultraviolet light source using a 3D printing device; the photosensitive ceramic-resin composite material is composed of HA / TCP (3:7); the thickness of each slice layer in the DLP is set to 30μm, and the exposure time is 5 seconds; after printing, the scaffold is separated from the support plate and thoroughly washed with sufficient distilled water to remove the remaining liquid slurry, and then the sample is heated to 600℃ at a heating rate of 2℃ / min and kept warm for 120min, and then it is further heated to 1100℃ at a heating rate of 1℃ / min and kept warm for another 120min to obtain a sintered bioceramic scaffold with a shrinkage rate of about 22%.

[0034] Through the present invention, not only the stable induction ability of enhancing blood vessels and bones is obtained at the cellular level, but also a highly efficient and stable bone augmentation effect is achieved in animals.

[0035] 1. Blood-sucking performance: When the stent is placed in the blood, it can quickly absorb blood within 1 second. Figure 5 .

[0036] 2. Angiogenic ability: The scaffold increases the expression of angiogenic genes in human endothelial cells and enhances the migration ability of cells. Figure 6 .

[0037] 3. Osteogenic ability: Through co-culture with osteoblast precursor cells, the results showed that the scaffold of the invention significantly promoted the osteogenic gene expression of osteoblast precursor cells, see Figure 7 .

[0038] 4. Animal in vivo validation: The scaffold was applied to the New Zealand rabbit bone augmentation model. We found that the scaffold can achieve a bone augmentation of about 4 mm, while the control group only has about 1.5 mm. Figure 8 .

Claims

1. A bionic rhizome structure bioceramic scaffold for bone augmentation, characterized by: The overall configuration of the bracket is a bionic rhizome structure. Specifically, its upper structure is a trunk-mimicking duct structure, and its lower structure is a rhizome-mimicking trabecular porous structure. The periphery of the bracket is wrapped by a solid side wall structure.

2. The bionic rhizome structure bioceramic scaffold for bone augmentation according to claim 1, characterized in that: The conduit structure is a conical channel structure, which is composed of a hexagonal cone channel, and the upper aperture is larger than the lower aperture.

3. The bionic rhizome structure bioceramic scaffold for bone augmentation according to claim 2, characterized in that: The upper aperture is 600-800um, and the lower aperture is 200-300um.

4. The bionic rhizome structure bioceramic scaffold for bone augmentation according to claim 1, characterized in that: The cross-section of the hole in the conduit structure can be hexagonal, circular, triangular or octagonal.

5. The bionic rhizome structure bioceramic scaffold for bone augmentation according to claim 1, characterized in that: The solid side wall has a thickness of 200-300um.

6. A method for manufacturing a bionic rhizome structure bioceramic scaffold for bone augmentation as claimed in any one of claims 1 to 5, comprising: Design a three-dimensional digital model of the bioceramic scaffold according to the size range of the defect and the required incremental height; The bioceramic scaffold was prepared under ultraviolet light using 3D printing equipment. After printing, the scaffold was separated from the support plate and thoroughly cleaned with sufficient distilled water to remove the remaining liquid slurry. The sample was then heated to 600°C at a heating rate of 2°C / min and kept warm for 120 min. Subsequently, it was further heated to 1100°C at a heating rate of 1°C / min and kept warm for another 120 min to obtain a sintered bioceramic scaffold.

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