Repair Of Bone Defects Research Articles

Collagen silver-doped hydroxyapatite scaffolds reinforced with 3D printed frameworks for infection prevention and enhanced repair of load-bearing bone defects.

Osteomyelitis, a severe bone infection, is an extremely challenging complication in the repair of traumatic bone defects. Furthermore, the use of long-term high-dose antibiotics in standard treatment increases the risks of antibiotic resistance. Herein, an antibiotic-free, collagen silver-doped hydroxyapatite (coll-AgHA) scaffold reinforced with a 3D printed polycaprolactone (PCL) framework was developed with enhanced mechanical properties to be used in the repair of load-bearing defects with antimicrobial properties as a preventative measure against osteomyelitis. The AgHA particles were fabricated in varying Ag doses and loaded within freeze-dried collagen scaffolds at two concentrations. The optimised Ag dose (1.5 mol% Ag) and AgHA concentration (200 wt%) within the collagen scaffold demonstrated in vitro osteogenic and antibacterial properties against Staphylococcus aureus (S. aureus), the main causative pathogen of osteomyelitis. The addition of the PCL framework to the coll-AgHA scaffolds significantly enhanced the compressive modulus from 4 kPa to 12 MPa while maintaining high porosity as well as both pro-osteogenic and antibacterial properties. The reinforced coll-AgHA scaffolds were implanted in vivo and demonstrated enhanced bone repair, significantly greater vessel formation, and calcified tissue in a load-bearing critical sized defect in rats. Taken together, these results confirm the capacity of this novel biomaterial scaffold as a preventative measure against infection in bone repair for use in load-bearing defects, without the use of antibiotics.&#xD.

Oriented Cortical-Bone-Like Silk Protein Lamellae Effectively Repair Large Segmental Bone Defects in Pigs.

Assembling natural proteins into large, strong, bone-mimetic scaffolds for repairing bone defects in large-animal load-bearing sites remain elusive. Here this challenge is tackled by assembling pure silk fibroin (SF) into 3D scaffolds with cortical-bone-like lamellae, superior strength, and biodegradability through freeze-casting. The unique lamellae promote the attachment, migration, and proliferation of tissue-regenerative cells (e.g., mesenchymal stem cells [MSCs] and human umbilical vein endothelial cells) around them, and are capable of developing in vitro into cortical-bone organoids with a high number of MSC-derived osteoblasts. High-SF-content lamellar scaffolds, regardless of MSC inoculation, regenerated more bone than non-lamellar or low-SF-content lamellar scaffolds. They accelerated neovascularization by transforming macrophages from M1 to M2 phenotype, promoting bone regeneration to repair large segmental bone defects (LSBD) in minipigs within three months, even without growth factor supplements. The bone regeneration can be further enhanced by controlling the orientation of the lamella to be parallel to the long axis of bone during implantation. This work demonstrates the power of oriented lamellar bone-like protein scaffolds in repairing LSBD in large animal models.

Evenly Distributed Microporous Structure and E7 Peptide Functionalization Synergistically Accelerate Osteogenesis and Angiogenesis in Engineered Periosteum.

Repairing large bone defects remains a significant clinical challenge. Stem cell is of great importance in bone regeneration, and periosteum is rich in periosteal stem cell, which has a great influence on repairing bone defects. Bioengineered periosteum with excellent biocompatibility and stem cell homing capabilities to promote bone regeneration is of great clinical significance. The E7 peptide (EPLQLKM), which exhibits a specific affinity for mesenchymal stem cells (MSCs), is beneficial for modulating cellular functions. In this study, a unique microporous structured carboxymethyl chitosan/sodium alginate membrane with a proper mass ratio is developed by the addition of Poloxam 407 （P407）, which is then functionalized with the E7 affinitive peptide. This membrane, characterized by its microporous structure and E7 peptide functionalization (CSSA/P/E), not only demonstrated favorable mechanical properties, enhanced hydrophilicity, satisfactory biodegradation profile, and excellent biocompatibility, but also synergistically enhanced MSCs recruitment. It is found to promote the proliferation, spreading, and osteogenic differentiation of MSCs in vitro and to accelerate early periosteal regeneration, bone matrix deposition, and vascularization in vivo, leading to effective regeneration of critical-sized bone defects. Overall, this study presents a robust, cell and growth factor-free strategy for bioengineering periosteum, offering a potential solution for the challenging large size bone defects.

Hyperbaric Oxygen Therapy for the Treatment of Bone-Related Diseases

Abstract: Hyperbaric oxygen therapy (HBOT) is a therapeutic modality that enhances tissue oxygenation by delivering 100% oxygen at pressures greater than 1 absolute atmosphere. In recent years, HBOT has shown considerable potential in the treatment of bone diseases. While excess oxygen was once thought to induce oxidative stress, recent studies indicate that when administered within safe limits, HBOT can notably promote bone healing and repair. Extensive basic research has demonstrated that HBOT can stimulate the proliferation and differentiation of osteoblasts and encourage bone angiogenesis. Furthermore, HBOT has been shown to exert a beneficial influence on bone metabolism by modulating the inflammatory response and redox status. These mechanisms are closely related to core issues of bone biology. Specifically, in the context of fracture healing, bone defect repair, and conditions such as osteoporosis, HBOT targets the key bone signaling pathways involved in bone health, thereby exerting a therapeutic effect. Several clinical studies have demonstrated the efficacy of HBOT in improving bone health. However, the optimal HBOT regimen for treating various bone diseases still requires further definition to expand the indications for its clinical application. This paper outlines the mechanisms of HBOT, focusing on its antioxidant stress, promotion of bone vascularization, and anti-inflammatory properties. The paper also describes the application of HBOT in orthopedic diseases, thereby providing a scientific basis for the development of precise and personalized HBOT treatment regimens in clinical orthopedics.

3D nanocomposites of β-TCP-H3BO3-Cu with improved mechanical and biological performances for bone regeneration applications

Recently, 3-D porous architecture of the composites play a key role in cell proliferation, bone regeneration, and anticancer activities. The osteoinductive and osteoconductive properties of β-TCP allow for the complete repair of numerous bone defects. Herein, β-TCP was synthesized by wet chemical precipitation route, and their 3-D porous composites with H3BO3 and Cu nanoparticles were prepared by the solid-state reaction method with improved mechanical and biological performances. Several characterization techniques have been used to investigate the various characteristics of fabricated porous composites. SEM and TEM studies revealed the porous morphology and hexagonal sheets of the β-TCP for the composite THC8 (82TCP-10H3BO3-8Cu). Moreover, the mechanical study showed excellent compressive strength (188 MPa), a high Young’s modulus (2.84 GPa), and elevated fracture toughness (9.11 MPa.m1/2). An in vitro study by MTT assay on osteoblast (MG-63) cells demonstrated no or minimal cytotoxicity at the higher concentration, 100 µg/ml after 24 h and it was found a more pronounced result at 20 µg/ml on increasing the concentration of Cu nanoparticles after incubating 72 h. The THC12 composite showed the highest antibacterial potency exclusively against B. subtilis. S. pyogene, S. typhi and E. coli. at 10 mg/ml, indicating its potential effectiveness in inhibiting all of these pathogens. Genotoxicity and cytotoxicity tests were also performed on rearing Drosophila melanogaster, and these findings did not detect any trypan blue-positive staining, which further recommended that the existence of composites did not harm the larval gut. Therefore, the fabricated porous composites THC8 and THC12 are suitable for bone regrowth without harming the surrounding cells and protect against bacterial infections.

Anti-aging chitosan/gelatin film crosslinked by α-Arbutin for bone regeneration by free radical scavenging to prevent osteoblast senescence.

Osteoblasts play a critical role in maintaining bone homeostasis. Senescence causes by free radical-mediated oxidative stress may affect the viability and osteogenic differentiation potential of osteoblast during bone formation. To eliminate the impacts of senescent cells by free radical scavenging is an optimal option for bone regeneration in age-related bone disease, such as osteoporosis (OP) and periodontitis. In this study, we fabricated an antioxidant film (CG-ARB) by crosslinking chitosan (C) and gelatin (G) using α-Arbutin (ARB) as a crosslinker. The morphological, physicochemical, and radical scavenging characteristics of the films were investigated. Its antioxidative ability to prevent osteoblast senescence for restoration of osteogenic differentiation was analyzed in vitro. A Sprague- Dawley (SD) rat model with critical size calvarial defect was used to evaluate the bone regeneration and biosafety in vivo. The results demonstrated that CG-ARB formed a dense fiber membrane, allowing for the gradual and sustained release of ARB for at least 10 days. ARB exerted antioxidant effect that prevented osteoblast senescence in vitro and promote bone healing in vivo. Furthermore, CG-ARB did not cause hemolysis or organ toxicity, and was therefore, considered biosafe. These results indicated that CG-ARB film could be an ideal drug delivery system (DDS) for sustained released of ARB in bone defect repair.

Ameliorating macrophage pyroptosis via ANXA1/NLRP3/Caspase-1/GSDMD pathway: Ac2-26/OGP-loaded intelligent hydrogel enhances bone healing in diabetic periodontitis

Craniofacial bone defect healing in periodontitis patients with diabetes background has long been difficult due to increased blood glucose levels which cause overproduction of reactive oxygen species (ROS) and a low pH environment. These conditions negatively affect the function of macrophages, worsen inflammation and oxidative stress, and ultimately, hinder osteoblasts' bone repair potential. In this study, we for the first time found that ANXA1 expression in macrophages was reduced in a diabetic periodontitis environment, with the activation of the NLRP3/Caspase-1/GSDMD signaling pathway, and, eventually, increased macrophage pyroptosis. Next, we have developed a new GPPG intelligent hydrogel system which was ROS and pH responsive, and loaded with Ac2-26, an ANXA1 bioactive peptide, and osteogenic peptide OGP as well. We found that Ac2-26/OGP/GPPG can effectively reduce ROS, mitigates macrophage pyroptosis via the ANXA1/NLRP3/Caspase-1/GSDMD pathway and enhanced osteogenic differentiation. The effect of Ac2-26/OGP/GPPG in regulation of pyroptosis and bone defect repair was also further validated by animal experiments on periodontitis-induced tooth loss model in diabetic rats. To conclude, our study unveils the effect of ANXA1 on macrophage pyroptosis in periodontitis patients with diabetes, based on which we introduced a promising innovative hydrogel system for improvement of bone defects repair in diabetic periodontitis patients via targeting macrophage pyroptosis and enhancing osteogenic potential.

Programmed Transformation of Osteogenesis Microenvironment by a Multifunctional Hydrogel to Enhance Repair of Infectious Bone Defects.

Repair of infectious bone defects remains a serious problem in clinical practice owing to the high risk of infection and excessive reactive oxygen species (ROS) during the early stage, and the residual bacteria and delayed Osseo integrated interface in the later stage, which jointly creates a complex and dynamic microenvironment and leads to bone non-union. The melatonin carbon dots (MCDs) possess antibacterial and osteogenesis abilities, greatly simplifying the composition of a multifunctional material. Therefore, a multifunctional hydrogel containing MCDs (GH-MCD) is developed to meet the multi-stage and complex repair needs of infectious bone injury in this study. The GH-MCD can intelligently release MCDs responding to the acidic microenvironment to scavenge intracellular ROS and exhibit good antibacterial activity by inducing the production of ROS in bacteria and inhibiting the expression of secA2. Moreover, it has high osteogenesis and long-lasting antimicrobial activity during bone repair. RNA-seq results reveal that the hydrogels promote the repair of infected bone healing by enhancing cellular resistance to bacteria, balancing osteogenesis and osteoclastogenesis, and regulating the immune microenvironment. In conclusion, the GH-MCD can promote the repair of infectious bone defects through the programmed transformation of the microenvironment, providing a novel strategy for infectious bone defects.

Masquelet Inspired in Vivo Engineered Extracellular Matrix as Functional Periosteum for Bone Defect Repair and Reconstruction.

The Masquelet technique that combines a foreign body reaction (FBR)-induced vascularized tissue membrane with staged bone grafting for reconstruction of segmental bone defect has gained wide attention in Orthopedic surgery. The success of Masquelet hinges on its ability to promote formation of a "periosteum-like" FBR-induced membrane at the bone defect site. Inspired by Masquelet's technique, here a novel approach is devised to create periosteum mimetics from decellularized extracellular matrix (dECM), engineered in vivo through FBR, for reconstruction of segmental bone defects. The approach involved 3D printing of polylactic acid (PLA) template with desired pattern/architecture, followed by subcutaneous implantation of the template to form tissue, and depolymerization and decellularization to generate dECM with interconnected channels. The dECM matrices produces from the same mice (autologous) or from different mice (allogenic) are used as a functional periosteum for repair of structural bone allograft in a murine segmental bone defect model. This study shows that autologous dECM performed better than allogenic dECM, further permitting local delivery of low dose BMP-2 to enhance allograft incorporation. The success of this current approach can establish a new line of versatile, patient-specific, and periosteum-like autologous dECM for bone regeneration, offering personalized therapeutics to patients with impaired healing.

Youthful Stem Cell Microenvironments: Rejuvenating Aged Bone Repair Through Mitochondrial Homeostasis Remodeling.

Extracellularmatrix (ECM) derived from mesenchymal stem cells regulates antioxidant properties and bone metabolism by providing a favorable extracellular microenvironment. However, its functional role and molecular mechanism in mitochondrial function regulation and aged bone regeneration remain insufficiently elucidated. This proteomic analysis has revealed a greater abundance of proteins supporting mitochondrial function in the young ECM (Y-ECM) secreted by young bone marrow-derived mesenchymal stem cells (BMMSCs) compared to the aged ECM (A-ECM). Further studies demonstrate that Y-ECM significantly rejuvenates mitochondrial energy metabolism in adult BMMSCs (A-BMMSCs) through the promotion of mitochondrial respiratory functions and amelioration of oxidative stress. A-BMMSCs cultured on Y-ECM exhibited enhanced multi-lineage differentiation potentials in vitro and ectopic bone formation in vivo. Mechanistically, silencing of silent information regulator type 3 (SIRT3) gene abolished the protective impact of Y-ECM on A-BMMSCs. Notably, a novel composite biomaterial combining hyaluronic acid methacrylate hydrogel microspheres with Y-ECM is developed, which yielded substantial improvements in the healing of bone defects in an aged rat model. Collectively, these findings underscore the pivotal role of Y-ECM in maintaining mitochondrial redox homeostasis and present a promising therapeutic strategy for the repair of aged bone defects.

The Impact of a Human Bone Morphogenetic Protein-infused Nano-Bone Material Combined With Traditional Chinese Medicine Carthamus tinctorius on the Repair of Oral Bone Defects.

The role of human bone morphogenetic protein-infused in combination with traditional Chinese medicine Carthamus tinctorius in repairing oral bone defects (OBD) was evaluated in this work. An experiment was conducted on a rat OBD model, where rats were randomly rolled into Groups A, B, and C based on their different treatments. Micro-CT was utilized to measure jaw bone volume fraction (BV/TV) and bone mineral density (BMD) in rats, while a biomechanical testing machine assessed compressive strength of the jaw bone. Cell culture technique was employed to measure the osteoblast proliferation rate (PR), and enzyme-linked immunosorbent assay was utilized to detect levels of alkaline phosphatase (ALP), osteocalcin (OCN), tumour necrosis factor-alpha (TNF-α), and interleukin (IL)-6 in the serum. Rats in Groups B and C showed higher jaw bone BV/TV, BMD, compressive strength, osteoblast PR, ALP, and OCN, demonstrating no great differences with Group A (P > .05). TNF-α and IL-6 in Groups B and C were lower in comparison with those in Group A (P > .05). Notably, Groups B and C exhibited statistically obvious differences in jaw bone BV/TV, BMD, osteoblast PR, ALP, OCN, TNF-α, and IL-6 levels (P > .05). The combined application of human bone morphogenetic protein-infused and traditional Chinese medicine C. tinctorius demonstrated positive effects on repair of OBD, reducing inflammatory response and promoting bone tissue repair and formation, thus effectively treating OBD.

Zinc-doped hydroxyapatite loaded chitosan gelatin nanocomposite scaffolds as a promising platform for bone regeneration

The advancement in the arena of bone tissue engineering persuades us to develop novel nanocomposite scaffolds in order to improve antibacterial, osteogenic, and angiogenic properties that show resemblance to natural bone extracellular matrix. Here, we focused on the development of novel zinc-doped hydroxyapatite (ZnHAP) nanoparticles (1, 2 and 3 wt%; size: 50-60 nm) incorporated chitosan-gelatin (CG) nanocomposite scaffold, with an interconnected porous structure. The addition of ZnHAP nanoparticles decreases the pore size (∼30 µm) of the CG scaffolds. It was observed that with the increase in the concentration of ZnHAP nanoparticles (3 wt%) in CG scaffolds, the swelling ratio (1760% ± 2.0%), porosity (71% ± 0.98%) and degradation rate (35%) decreased, whereas mechanical property (1 MPa) increased, which was better as compared to control (CG) samples. Similarly, the high deposition of apatite crystals especially CG-ZnHAP3nanocomposite scaffold revealed the excellent osteoconductive potential among all other scaffolds. MC3T3-E1 osteoblastic cells seeded with CG-ZnHAP nanocomposite scaffolds depicted better cell adhesion, proliferation and differentiation to osteogenic lineages. Finally, the chorioallantoic membrane (CAM) assay revealed better angiogenesis of ZnHAP nanoparticles (3 wt%) loaded CG scaffolds supporting vascularization after 7th day incubation in the CAM area. Overall, the results showed that the CG-ZnHAP3nanocomposite scaffold could be a potential candidate for bone defect repair.

Research progress of bioactive scaffolds in repair and regeneration of osteoporotic bone defects

To summarize the research progress of bioactive scaffolds in the repair and regeneration of osteoporotic bone defects. Recent literature on bioactive scaffolds for the repair of osteoporotic bone defects was reviewed to summarize various types of bioactive scaffolds and their associated repair methods. The application of bioactive scaffolds provides a new idea for the repair and regeneration of osteoporotic bone defects. For example, calcium phosphate ceramics scaffolds, hydrogel scaffolds, three-dimensional (3D)-printed biological scaffolds, metal scaffolds, as well as polymer material scaffolds and bone organoids, have all demonstrated good bone repair-promoting effects. However, in the pathological bone microenvironment of osteoporosis, the function of single-material scaffolds to promote bone regeneration is insufficient. Therefore, the design of bioactive scaffolds must consider multiple factors, including material biocompatibility, mechanical properties, bioactivity, bone conductivity, and osteogenic induction. Furthermore, physical and chemical surface modifications, along with advanced biotechnological approaches, can help to improve the osteogenic microenvironment and promote the differentiation of bone cells. With advancements in technology, the synergistic application of 3D bioprinting, bone organoids technologies, and advanced biotechnologies holds promise for providing more efficient bioactive scaffolds for the repair and regeneration of osteoporotic bone defects.

Posterior lateral perforator flap in lower limb combined with free fibula for maxillary tissue defect repair

To investigate the effectiveness of posterior lateral perforator flap in lower limb combined with free fibula for maxillary tissue defect repair. Between December 2018 and December 2023, 16 patients with the maxillary malignant tumors were admitted. There were 10 males and 6 females, with an average age of 64.3 years (range, 54-75 years). There were 7 cases of maxillary gingival cancer, 5 cases of hard palate cancer, and 4 cases of maxillary sinus cancer. According to the 2017 American Joint Committee on Cancer (AJCC) TNM stage, there were 8 cases of stage Ⅲ, 6 cases of stage Ⅳa, and 2 cases of stage Ⅳb. After resection of the lesion, the remaining maxillary defects were classified into class Ⅱa in 3 cases, class Ⅱb in 5 cases, and class Ⅲb in 8 cases according to Brown's classification. The size of soft tissue defects ranged from 4 cm×3 cm to 8 cm×6 cm. The posterior lateral perforator flap in lower limb in size of 5 cm×4 cm-9 cm×7 cm were harvested to repair soft tissue defects, and free fibula in length of 6-11 cm were used to repair bone defects. The donor sites of the lower limb were sutured directly (6 cases) or repaired with free skin grafting (10 cases). Six patients with positive lymph node pathology were treated with radiotherapy after operation. At 6 and 12 months after operation, the self-assessment was performed by the University of Washington Quality of Survival Questionnaire Form (QUW-4) in five dimensions (facial appearance, swallowing function, chewing function, speech function, and mouth opening), and swallowing function was evaluated by using the Kubota water swallowing test. Postoperative pathological examination showed that all patients were squamous cell carcinoma. One patient who was treated with radiotherapy developed osteomyelitis and 1 patient developed venous crisis of skin flap. The rest of the flaps and all skin grafts survived, and the wounds healed by first intention. All patients were followed up 1-5 years (mean, 2.8 years). Two patients died of local recurrence of the tumor at the 4th and 5th years after operation, respectively. Except for the chewing function score and total score at 6 months after operation, which showed significant differences compared to preoperative scores ( P<0.05), there was no significant difference in other QUW-4 scale scores between different time points ( P>0.05). The patients' swallowing function evaluated by Kubota water swallowing test reached normal in 4 cases, suspicious in 9 cases, and abnormal in 3 cases at 6 months after operation, and 10, 6, and 0 cases at 12 months after operation, respectively. The swallowing function at 12 months was significantly better than that at 6 months ( Z=-2.382, P=0.017). The posterior lateral perforator flap in the lower limb combined with free fibula to repair maxillary tissue defects can repair soft and hard tissue defects at the same time, so that the patient's facial appearance, swallowing function, chewing function, speech function, and mouth opening are satisfactorily restored and the mid-term effectiveness is good.

Cellulose nanofiber reinforced curcumin-infused calcium phosphate silicate cement for various bone-tissue engineering application.

This study utilized a injectable curcumin (Cur)-infused calcium phosphate silicate cement (CPSC) for addressing defects caused by bone cancer, and evaluated its promoting bone regeneration and exerting cytotoxic effects on osteosarcoma cells. The material's physicochemical properties, biocompatibility with osteoblasts, and cytotoxicity toward osteosarcoma cells were rigorously analyzed. The findings demonstrate that CPSC-Cur signicantly prolongs the setting time, which can be optimized by adding silanized cellulose nanober (CNF-SH) to achieve a balance between workability and mechanical strength. Biological assessments reveal a pronounced cytotoxic effect on osteosarcoma cells while maintaining minimal toxicity toward pre-osteoblasts, highlighting CPSC-Cur's potential as a promising material for repairing bone defects following cancer removal. This study lays the groundwork for future investigations into CPSC-Cur's in vivo efficacy and its role in the clinical treatment of bone cancer.

Differential bone and vessel type formation at superior and dura periosteum during cranial bone defect repair

The cranial mesenchyme, originating from both neural crest and mesoderm, imparts remarkable regional specificity and complexity to postnatal calvarial tissue. While the distinct embryonic origins of the superior and dura periosteum of the cranial parietal bone have been described, the extent of their respective contributions to bone and vessel formation during adult bone defect repair remains superficially explored. Utilizing transgenic mouse models in conjunction with high-resolution multiphoton laser scanning microscopy (MPLSM), we have separately evaluated bone and vessel formation in the superior and dura periosteum before and after injury, as well as following intermittent treatment of recombinant peptide of human parathyroid hormone (rhPTH), Teriparatide. Our results show that new bone formation along the dura surface is three times greater than that along the superior periosteal surface following injury, regardless of Teriparatide treatment. Targeted deletion of PTH receptor PTH1R via SMA-CreER and Col 1a (2.3)-CreER results in selective reduction of bone formation, suggesting different progenitor cell pools in the adult superior and dura periosteum. Consistently, analyses of microvasculature show higher vessel density and better organized arterial-venous vessel network associated with a 10-fold more osteoblast clusters at dura periosteum as compared to superior periosteum. Intermittent rhPTH treatment further enhances the arterial vessel ratio at dura periosteum and type H vessel formation in cortical bone marrow space. Taken together, our study demonstrates a site-dependent coordinated osteogenic and angiogenic response, which is determined by regional osteogenic progenitor pool as well as the coupling blood vessel network at the site of cranial defect repair.

Biological Behavior of Bioactive Glasses SinGlass (45S5) and SinGlass High (F18) in the Repair of Critical Bone Defects.

This study evaluated the osteogenic potential of the bioactive glasses SinGlass (45S5) and SinGlass High (F18) in regenerating critical bone defects in rat calvaria. Both biomaterials promoted new bone formation around the particles, with the SinGlass High (F18) group exhibiting a higher rate of bone maturation. Histomorphological and birefringence analyses revealed better organization of the newly formed bone in the biomaterial-treated groups, and immunohistochemistry indicated the expression of osteogenic markers such as osteocalcin, immunostaining for bone morphogenetic protein 2 (BMP 2), and immunostaining for bone morphogenetic protein 4 (BMP 4). Microtomography computadorized (Micro-CT) revealed centripetal bone formation in both groups, with greater integration of the particles into the surrounding bone tissue. The superior performance of SinGlass High (F18) was attributed to its higher potassium and magnesium content, which enhance osteoconductivity. After 42 days, the SinGlass High (F18) group showed the highest percentage of new bone formation, in line with previous studies. Although our results are promising, the limited follow-up period and use of a single animal model highlight the need for further research to validate clinical applicability. SinGlass High (F18) appears to be a viable alternative to autografts in bone repair, with potential to improve tissue integration and accelerate recovery.

Application of Light-Responsive Nanomaterials in Bone Tissue Engineering.

The application of light-responsive nanomaterials (LRNs) in bone tissue engineering shows broad prospects, especially in promoting bone healing and regeneration. With a deeper understanding of the mechanisms of bone defects and healing disorders, LRNs are receiving increasing attention due to their non-invasive, controllable, and efficient properties. These materials can regulate cellular biological reactions and promote bone cell adhesion, proliferation, and differentiation by absorbing specific wavelengths of light and converting them into physical and chemical signals. In addition, the unique surface morphology and biocompatibility of LRNs enable them to effectively load drugs in bone tissue engineering, achieve precise release, and optimize the bone regeneration process. Through photothermal and photodynamic therapy, these materials also possess antibacterial properties and can play an important role in the repair of infectious bone defects. Although LRNs have shown significant advantages in bone tissue regeneration, a series of challenges still need to be overcome to achieve their widespread and effective clinical applications. This article summarizes the basic principles, classification, and potential applications of LRNs in bone tissue regeneration, aiming to provide reference for future research and clinical applications.

Evaluation of osseointegration of plasma treated polyaryletherketone maxillofacial implants

Osseointegration is a crucial property of biomaterials used for bone defect repair. While titanium is the gold standard in craniofacial surgeries, various polymeric biomaterials are being explored as alternatives. However, polymeric materials can be bioinert, hindering integration with surrounding tissues. In this investigation, plasma ion immersion implantation (PIII)-treated polyether ether ketone (PEEK) and polyether ketone (PEK) implants were assessed in a sheep maxilla and mandible model. Defects were filled with PIII-treated PEEK and PEK implants, produced through fused filament fabrication (FFF) and selective laser sintering (SLS), respectively. Positive controls were grade 23 titanium implants via selective laser melting, while untreated PEEK implants served as negative controls. Surface analyses using scanning electron microscopy and atomic force microscopy revealed favorable properties. Osseointegration was qualitatively and quantitatively assessed at 8-, 10-, and 12-weeks post-implantation, showing significantly improved outcomes for both PIII-treated PEEK and PEK implants compared to untreated controls. The study suggests PIII treatment enhances FFF-printed PEEK’s osseointegration, and PIII-treated SLS-printed PEK achieves comparable osseointegration to 3D printed titanium. These findings underscore surface modification strategies’ potential for polymeric biomaterials, offering insights into developing alternative implant materials for craniofacial surgeries, with enhanced biocompatibility and osseointegration capabilities for improved clinical outcomes.

3D printing of different fibres towards HA/PCL scaffolding induces macrophage polarization and promotes osteogenic differentiation of BMSCs.

With the rise of bone tissue engineering (BET), 3D-printed HA/PCL scaffolds for bone defect repair have been extensively studied. However, little research has been conducted on the differences in osteogenic induction and regulation of macrophage (MPs) polarisation properties of HA/PCL scaffolds with different fibre orientations. Here, we applied 3D printing technology to prepare three sets of HA/PCL scaffolds with different fibre orientations (0-90, 0-90-135, and 0-90-45) to study the differences in physicochemical properties and to investigate the response effects of MPs and bone marrow mesenchymal stem cells (BMSCs) on scaffolds with different fibre orientations. The results showed that multi-angle staggered fibres affected the overall porosity and compressive strength of the scaffolds. Compared with the other two groups, the 0-90-45 scaffold induced osteogenic differentiation of BMSCs more significantly, while promoting the polarisation of MPs towards the M2 phenotype to form an osteogenic-friendly immune microenvironment. Unexpectedly, the 0-90-45 scaffold significantly upregulated the expression of angiogenic genes (PDGF, VEGF). Therefore, we conclude that the multi-angle interlaced fibres better mimic the physiological structure of cancellous bone, and that the excellent biomimetic properties reflect the best in vitro osteogenic, immunomodulatory and angiogenic effects. In conclusion, this study is a step forward in the exploration of BET scaffolds and provides a very promising bone filling material.