Objective To review the research progress of in-situ three dimensional (3D) bio-printing technology in the repair of bone and cartilage injuries. Methods Literature on the application of in-situ 3D bio-printing technology to repair bone and cartilage injuries at home and abroad in recent years was reviewed, analyzed, and summarized. Results As a new tissue engineering technology, in-situ 3D bio-printing technology is mainly applied to repair bone, cartilage, and skin tissue injuries. By combining biomaterials, bioactive substances, and cells, tissue is printed directly at the site of injury or defect. At present, the research on the technology mainly focuses on printing mode, bio-ink, and printing technology; the application research in the field of bone and cartilage mainly focuses on pre-vascularization, adjusting the composition of bio-ink, improving scaffold structure, printing technology, loading drugs, cells, and bioactive factors, so as to promote tissue injury repair. Conclusion Multiple animal experiments have confirmed that in-situ 3D bio-printing technology can construct bone and cartilage tissue grafts in a real-time, rapid, and minimally invasive manner. In the future, it is necessary to continue to develop bio-inks suitable for specific tissue grafts, as well as combine with robotics, fusion imaging, and computer-aided medicine to improve printing efficiency.
Bone tissue regeneration and blood vessel formation are inseparable. How to realize the vascularization of bone repair scaffolds is an urgent problem in bone tissue engineering. The growth and development, mineralization maturity, reconstruction and remodeling, and tissue regeneration of bone are all based on forming an excellent vascularization network. In recent years, more and more researchers have used hydrogels to carry different cells, cytokines, metal ions and small molecules for in vitro vascularization and application in bone regeneration. Based on this background, this article reviews the hydrogel-based vascularization strategies in bone tissue engineering.
ObjectiveTo summarize the clinical application and research status of bioactive glass (BAG) in bone repair.MethodsThe recently published literature concerning BAG in bone repair at home and abroad was reviewed and summarized.ResultsBAG has been widely used in clinical bone repair with a favorable effectiveness. In the experimental aspect, to meet different clinical application needs, BAG has been prepared in different forms, such as particles, prosthetic coating, drug and biological factor delivery system, bone cement, and scaffold. And the significant progress has been made.ConclusionBAG has been well studied in the field of bone repair due to its excellent bone repair performance, and it is expected to become a new generation of bone repair material.
Objective To review the research and application progress of bioactive glass in bone repair. Methods The recently published literature concerning bioactive glass in bone repair was reviewed and summarized. Results Bioactive glass can classified different types, such as bioactive glass particulate, bioactive glass scaffold, bioactive glass coating, injectable bioactive glass cement, and bioactive glass delivery system. Bioactive glass has been well studied in the field of bone repair due to its excellent biological properties. Also, the remarkable progress has been made in various aspects. Conclusion Bioactive glass is a reliable material of bone repair and will play an even more important role in the future.
Objective To review the osteoimmunomodulatory effects and related mechanisms of inorganic biomaterials in the process of bone repair. Methods A wide range of relevant domestic and foreign literature was reviewed, the characteristics of various inorganic biomaterials in the process of bone repair were summarized, and the osteoimmunomodulatory mechanism in the process of bone repair was discussed. Results Immune cells play a very important role in the dynamic balance of bone tissue. Inorganic biomaterials can directly regulate the immune cells in the body by changing their surface roughness, surface wettability, and other physical and chemical properties, constructing a suitable immune microenvironment, and then realizing dynamic regulation of bone repair. Conclusion Inorganic biomaterials are a class of biomaterials that are widely used in bone repair. Fully understanding the role of inorganic biomaterials in immunomodulation during bone repair will help to design novel bone immunomodulatory scaffolds for bone repair.
In recent years, 3D printing technology, as a new material processing technology, can precisely control the macroscopic and microstructure of biological scaffolds and has advantages that traditional manufacturing methods cannot match in the manufacture of complex bone repair scaffolds. Magnesium ion is one of the important trace elements of the human body. It participates in many physiological activities of the body and plays a very important role in maintaining the normal physiological function of the organism. In addition, magnesium ions also have the characteristics of promoting the secretion of osteogenic proteins by osteoblasts and osteogenic differentiation of mesenchymal stem cells. By combining with 3D printing technology, more and more personalized magnesium-based biological scaffolds have been produced and used in bone regeneration research in vivo and in vitro. Therefore, this article reviews the application and research progress of 3D printing magnesium-based biomaterials in the field of bone regeneration and repair.
Infectious bone defects are usually caused by trauma, surgical infections, or chronic osteomyelitis, and represent a complex and intractable clinical challenge in the field of orthopaedics. Biological scaffolds can achieve synergistic repair of defects by loading antibiotics for controlled release to inhibit bacteria, providing support for cell proliferation and differentiation to promote bone regeneration, and carrying factors or stem cells to enhance vascularization. They possess incomparable advantages over traditional treatment methods in the management of infectious bone defects, and the selection of appropriate biological scaffolds in clinical practice needs to be tailored to the type of defect and the severity of infection. Therefore, this article elaborates on the application and research progress of biological scaffolds in the treatment of infectious bone defects.
Objective To review the research progress on bone repair biomaterials with the function of recruiting endogenous mesenchymal stem cells (MSCs). Methods An extensive review of the relevant literature on bone repair biomaterials, particularly those designed to recruit endogenous MSCs, was conducted, encompassing both domestic and international studies from recent years. The construction methods and optimization strategies for these biomaterials were summarized. Additionally, future research directions and focal points concerning this material were proposed. Results With the advancement of tissue engineering technology, bone repair biomaterials have increasingly emerged as an ideal solution for addressing bone defects. MSCs serve as the most critical “seed cells” in bone tissue engineering. Historically, both MSCs and their derived exosomes have been utilized in bone repair biomaterials; however, challenges such as limited sources of MSCs and exosomes, low survival rates, and various other issues have persisted. To address these challenges, researchers are combining growth factors, bioactive peptides, specific aptamers, and other substances with biomaterials to develop constructs that facilitate stem cell recruitment. By optimizing mechanical properties, promoting vascular regeneration, and regulating the microenvironment, it is possible to create effective bone repair biomaterials that enhance stem cell recruitment. Conclusion In comparison to cytokines, phages, and metal ions, bioactive peptides and aptamers obtained through screening exhibit more specific and targeted recruitment functions. Future development directions for bone repair biomaterials will involve the modification of peptides and aptamers with targeted recruitment capabilities in biological materials, as well as the optimization of the mechanical properties of these materials to enhance vascular regeneration and adjust the microenvironment.
Polyetheretherketone is one of the most commonly used materials for the production of orthopaedic implants, but the osseointegration capacity of polyetheretherketone is poor because of its bioinert surface, which greatly limits its clinical application. In recent years, scholars have carried out a lot of research on the modification of polyetheretherketone materials in order to improve its osseointegration capacity. At present, the modification of polyetheretherketone is mainly divided into surface modification and blend modification. Therefore, this paper summarizes the research progress of polyetheretherketone material modification technology and its influence on osseointegration from two aspects of surface modification and blend modification for polyetheretherketone materials used in the field of bone repair, so as to provide a reference for the improvement and transformation of polyetheretherketone materials for bone repair in the future.
Objecitve To investigate the effectiveness of three-dimensional (3D) printing-assisted vascularized fibular graft for repairing metatarsal defects. Methods Between November 2021 and February 2024, 11 patients with varying degrees of metatarsal defects caused by trauma were treated. There were 10 males and 1 female, aged 22-67 years, with a mean age of 51.2 years. The defect locations were as follows: the first metatarsal in 4 cases, the fifth metatarsal in 2 cases, the first and the second metatarsals in 1 case, the first to third metatarsals in 1 case, the third and the fourth metatarsals in 1 case, the third to fifth metatarsals in 1 case, and the first to fifth metatarsals in 1 case. The preoperative American Orthopaedic Foot & Ankle Society (AOFAS) score was 67.0 (48.5, 72.5). Based on 3D-printed bilateral feet models and mirrored healthy-side foot arch angles for preoperative planning and design, the vascularized fibular graft was performed to repair the metatarsal defects. At last follow-up, the medial and lateral longitudinal arches of bilateral feet were measured on weight-bearing X-ray films, and functional assessment was conducted using the AOFAS score.Results All operations were successfully completed, with an operation time ranging from 180 to 465 minutes (mean, 246.8 minutes). All incisions healed by first intention, with no occurrence of osteomyelitis. All patients were followed up 6-22 months (mean, 10 months). X-ray film reviews showed bone graft healing in all cases, with a healing time of 3-6 months (mean, 5 months). All patients underwent internal fixator removal at 6-12 months after operation. At last follow-up, no significant difference was observed in the medial and lateral longitudinal arches between the healthy and affected feet (P>0.05). The AOFAS score of the affected foot was 78.0 (73.5, 84.0), showing a significant improvement compared to the preoperative score (P<0.05). The effectiveness was rated as excellent in 1 case, good in 7 cases, fair in 2 cases, and poor in 1 case. Linear scarring remained at the donor site, with no functional impairment in adjacent joint movement. Conclusion 3D printing-assisted vascularized fibular graft for repairing metatarsal defects can effectively restore the physiological angle of the foot arch, facilitate the recovery of weight-bearing alignment, promote good bone healing, and yield satisfactory clinical outcomes.