In recent years,the number of patients with orthopedic diseases such as cervical spondylosis has increased,resulting in an increase in the demand for orthopedic surgery.However,thermal necrosis and bone cracks caused ...In recent years,the number of patients with orthopedic diseases such as cervical spondylosis has increased,resulting in an increase in the demand for orthopedic surgery.However,thermal necrosis and bone cracks caused by surgery severely restrict the development and progression of orthopedic surgery.For the material of cutting tool processing bone in bone surgery of drilling high temperature lead to cell death,easy to produce the problem such as crack cause secondary damage effects to restore,in this paper,a bionic drill was designed based on the micro-structure of the dung beetle's head and back.The microstructure configuration parameters were optimized by numerical analysis,and making use of the optical fiber laser marking machine preparation of bionic bit;through drilling test,the mathematical model of drilling temperature and crack generation based on micro-structure characteristic parameters was established by infrared thermal imaging technology and acoustic emission signal technology,and the cooling mechanism and crack suppression strategy were studied.The experimental results show that when the speed is 60 m/min,the cooling effects of the bionic bit T1 and T2 are 15.31%and 19.78%,respectively,and both kinds of bits show obvious crack suppression effect.The research in this paper provides a new idea for precision and efficient machining of bone materials,and the research results will help to improve the design and manufacturing technology and theoretical research level in the field of bone drilling tools.展开更多
Objective： To evaluate the effect of autologous bone marrow mesenchymal stem cells （BMSCs） seeded bio-derived bone materials （BBM） combined with recombinant human bone morphogenetic protein-2 （rhBMP-2） in repai...Objective： To evaluate the effect of autologous bone marrow mesenchymal stem cells （BMSCs） seeded bio-derived bone materials （BBM） combined with recombinant human bone morphogenetic protein-2 （rhBMP-2） in repairing defect of osteonecrosis of femoral head （ONFH）. Methods： Early-stage osteonecrosis in the left hip was induced in 36 adult New Zealand white rabbits （provided by the Animal Center of Guangxi Medical University, Nanning, China） after core decompression and delivery of liquid nitrogen into the femoral head. Then the animals were divided into three groups according to the type of implants for bone repair： 12 rabbits with nothing （Group Ⅰ, the blank control group）, 12 with BBM combined with rhBMP-2 （Group Ⅱ）, and 12 with BMSCs-seeded BBM combined with rhBMP-2 （Group Ⅲ）. At 4, 8, and 12 weeks after surgery, X-ray of the femoral head of every 4 rabbits in each group was taken, and then they were killed and the femoral heads were collected at each time point, respectively. Gross observation was made on the femoral heads. After hematoxylin and eosin staining, Lane-sandhu scores of X-ray and bone densitometry were calculated and the histomorphometric measurements were made for the new bone trabeculae. Results： At 12 weeks after surgery, two femoral heads collapsed in Group Ⅰ, but none in Group Ⅱ or Group Ⅲ. X-ray examination showed that the femoral heads in Group I had defect shadow or collapsed while those in Group II had a low density and those in Group III presented with a normal density. Histologically, the defects of femoral heads were primarily filled with no new bone but fibrous tissues in Group Ⅰ. In contrast, new bone regeneration and fibrous tissues occurred in Group II and only new bone regeneration occurrd in Group Ⅲ. Lane-sandhu scores of X-ray, bone mineral density and rate of new bone in trabecular area in Group Ⅲ were higher significantly than those of the other two groups. Conclusions： Our findings indicate a superior choice of repairing the experimental defect of OFH with BMSCsseeded BBM combined with rhBMP-2.展开更多
In this study, ultrasonic backscattering signals in cancellous bones were obtained by finite difference time domain （FDTD） simulations, and the effect of trabecular material properties on these signals was analyzed....In this study, ultrasonic backscattering signals in cancellous bones were obtained by finite difference time domain （FDTD） simulations, and the effect of trabecular material properties on these signals was analyzed. The backscatter coefficient （BSC） and integrated backscatter coefficient （IBC） were numerically investigated for varying trabecular bone material properties, including density, Lame coefficients, viscosities, and resistance coefficients. The results show that the BSC is a complex function of trabecular bone density, and the IBC increases as density increases. The BSC and IBC increase with the first and second Lame coefficients. While not very sensitive to the second viscosity of the trabeculae, the BSC and IBC decrease as the first viscosity and resistance coefficients increase. The results demonstrate that, in addition to bone mineral density （BMD） and microarchitecture, trabecular material properties significantly influence ultrasonic backseattering signals in cancellous bones. This research furthers the understanding of ultrasonic backscattering in cancellous bones and the characterization of cancellous bone status.展开更多
BACKGROUND Tibial plateau fractures often require structural support for metaphyseal defects created during articular reduction.While autologous bone grafting has been utilized as the gold standard,bone substitutes of...BACKGROUND Tibial plateau fractures often require structural support for metaphyseal defects created during articular reduction.While autologous bone grafting has been utilized as the gold standard,bone substitutes offer advantages including reduced donor site morbidity.Our meta-analysis evaluated the comparative efficacy of these approaches across clinical and operative outcomes.AIM To conduct a systematic review and meta-analysis of randomized controlled trials comparing autologous bone grafts with bone substitutes for tibial plateau fractures.METHODS We conducted a systematic review and meta-analysis of randomized controlled trials comparing autologous bone grafts with bone substitutes for tibial plateau fractures.Primary outcomes included joint depression,secondary collapse rate,operative time,blood loss,and infection rate.Subgroup analyses were performed by fracture complexity,geographic region,and methodological factors.In addition to that,we also developed a combined outcome score integrating structural,procedural,and complication domains.RESULTS Seven randomized controlled trials with 424 patients(296 bone substitute,128 autograft)were included.No significant differences in joint depression or secondary collapse were observed across fracture complexity categories.Geographic variations were evident,with Western studies showing significantly higher risk of secondary collapse with autografts(risk ratio=1.45,P value=0.02).Both Western and Asian studies have demonstrated significantly reduced blood loss with bone substitutes(70-90 mL less),while operative time reduction was more significant in the Asian studies(23.65 vs 8.00 minutes,P value=0.04 for subgroup difference).The combined outcome score(standardized effect size-0.2481)favored bone substitutes,primarily due to procedural advantages.CONCLUSION Bone substitutes provide similar structural outcomes to autologous bone grafts while having better procedural advantages in tibial plateau fracture management.These findings support bone substitutes as a viable option across fracture patterns.Future studies should focus on specific bone substitute formulations and cost-effectiveness analyses.展开更多
Objective:To prepare a bone repair material with certain mechanical strength and biological activity,this paper used calcium sulfate hemihydrate(CSH)powder compounded with calcium hydroxide(Ca(OH)2)powder to prepare a...Objective:To prepare a bone repair material with certain mechanical strength and biological activity,this paper used calcium sulfate hemihydrate(CSH)powder compounded with calcium hydroxide(Ca(OH)2)powder to prepare a bone repair scaffold material for physicochemical property characterization and testing.Methods:The physical and chemical properties and characterization of the dried and cured bone repair materials were determined by Fourier infrared spectroscopy(FT-IR),X-ray diffraction(XRD),and scanning electron microscopy;Universal material testing machine to determine the mechanical and mechanical strength of composite materials.Results:XRD showed that the structure of the composite material phase at 5%concentration was calcium sulfate hemihydrate and calcium hydroxide after hydration.The FT-IR and XRD analyses were consistent.Scanning electron microscopy(SEM)results showed that calcium hydroxide was uniformly dispersed in the hemihydrate calcium sulfate material.0%,1%,5%,and 10%specimen groups had compressive strengths of 3.86±3.1,5.27±1.28,8.22±0.96,and 14.4±3.28 MPa.10%addition of calcium hydroxide significantly improved the mechanical strength of the composites,but also reduced the the porosity of the material.Conclusion:With the addition of calcium hydroxide,the CSH-Ca(OH)2 composite was improved in terms of mechanical material and is expected to be a new type of bone repair material.展开更多
Tissue engineering aims to offer large-scale replacement of damaged organs using implants with the com-bination of cells,growth factors and scaffolds.However,the intra/peri-implant region is exposed to se-vere hypoxic...Tissue engineering aims to offer large-scale replacement of damaged organs using implants with the com-bination of cells,growth factors and scaffolds.However,the intra/peri-implant region is exposed to se-vere hypoxic stress and oxidative stress during the early stage of implantation with bone graft materials,which endangers the survival,proliferation and differentiation of seed cells within the implants as well as the host cells surrounding the implants.If the bone graft material could spontaneously and intelligently regulate the hypoxic stress and oxidative stress to a moderate level,it will facilitate the vascularization of the implants and the rapid regeneration of the bone tissue.In this review,we will first introduce the signaling pathways of cellular response under hypoxic stress and oxidative stress,then present the clas-sical material designs and examples in response to hypoxic stress and oxidative stress.And finally,we will address the important role of epigenetic mechanisms in the regulation of hypoxic stress and oxida-tive stress and describe the potential applications and prospective smart bone graft materials based on novel epigenetic factors against hypoxic stress and oxidative stress in bone repair.The main content of this review is summarized in the following graphical abstract.展开更多
One of the biggest challenges in the biocompatibility of implantable metals is the prevention of the stress shielding effect,which is related to the coupling of the bone-metal mechanical properties.This stress shieldi...One of the biggest challenges in the biocompatibility of implantable metals is the prevention of the stress shielding effect,which is related to the coupling of the bone-metal mechanical properties.This stress shielding phenomenon provokes bone resorption and the consequent adverse effects on prosthesis fixation.However,it can be inhibited by adapting the stiffness of the implant material.Since the use of titanium(Ti)porous structures is a great alternative not only to inhibit this effect but also to improve the osteointegration of orthopedic and dental implants,a brief description of the techniques used for their manufacturing and a review of the current commercialized implants produced from porous Ti assemblies are compiled in this work.As powder metallurgy(PM)with space holder(SH)is a powerful technology used to produce porous Ti structures,it is here discussed its potential for the fabrication of medical devices from the perspectives of both design and manufacture.The most important parameters of the technique such as the size and shape of the initial metallic particles,the SH and binder type of materials,the compaction pressure of the green form,and in the sintering stage,the temperature,atmosphere,and time are reviewed according to the bibliography reported.Furthermore,the importance of the porosity and its types together with the influence of the mentioned parameters in the final porosity and,consequently,in the ultimate mechanical properties of the structure are discussed.Finally,a few examples of the PM-SH application for the manufacturing of orthopedic implants are presented.展开更多
Porous silicon carbide(SiC)has a specific biomorphous microstructure similar to the trabecular microstructure of human bone.Compared with that of bioactive ceramics,such as calcium phosphate,SiC does not induce sponta...Porous silicon carbide(SiC)has a specific biomorphous microstructure similar to the trabecular microstructure of human bone.Compared with that of bioactive ceramics,such as calcium phosphate,SiC does not induce spontaneous interface bonding to living bone.In this study,bioactive tantalum(Ta)metal deposited on porous SiC scaffolds by chemical vapour deposition was investigated to accelerate osseointegration and improve the bonding to bones.Scanning electron microscopy indicated that the Ta coating evenly covered the entire scaffold structure.Energy-dispersive spectroscopy and X-ray diffraction analysis showed that the coating consisted of Ta phases.The bonding strength between the Ta coating and the SiC substrate is 88.4MPa.The yield strength of porous SiC with a Ta coating(pTa)was 45.862.9MPa,the compressive strength was 61.463.2MPa and the elasticmodulus was4.8GPa.When MG-63 human osteoblasts were co-cultured with pTa,osteoblasts showed good adhesion and spreading on the surface of the pTa and its porous structure,which showed that it has excellent bioactivity and cyto-compatibility.To further study the osseointegration properties of pTa.PTa and porous titanium(pTi)were implanted into the femoral neck of goats for 12weeks,respectively.The Van-Gieson staining of histological sections results that the pTa group had better osseointegration than the pTi group.These results indicate that coating bioactive Ta metal on porous SiC scaffolds could be a potential material for bone substitutes.展开更多
Minimally invasive injectable self-setting materials are useful for bone repairs and for bone tissue regeneration in situ. Due to the potential advantages of these materials, such as causing minimal tissue injury, nea...Minimally invasive injectable self-setting materials are useful for bone repairs and for bone tissue regeneration in situ. Due to the potential advantages of these materials, such as causing minimal tissue injury, nearly no influence on blood supply, easy operation and negligible postoperative pain, they have shown great promises and successes in clinical applications. It has been proposed that an ideal injectable bone repair material should have features similar to that of natural bones, in terms of both the microstructure and the composition, so that it not only provides adequate stimulus to facilitate cell adhesion, proliferation and differentiation but also offers a satisfactory biological environment for new bone to grow at the implantation site. This article reviews the properties and applications of injectable bone repair materials, including those that are based on natural and synthetic polymers, calcium phosphate, calcium phosphate/ polymer composites and calcium sulfate, to orthopedics and bone tissue repairs, as well as the progress made in biomimetic fabrication of injectable bone repair materials.展开更多
The fate of mesenchymal stem cells(MSCs)is regulated by biological,physical and chemical signals.Developments in biotechnology and materials science promoted the occurrence of bioactive materials which can provide phy...The fate of mesenchymal stem cells(MSCs)is regulated by biological,physical and chemical signals.Developments in biotechnology and materials science promoted the occurrence of bioactive materials which can provide physical and chemical signals for MSCs to regulate their fate.In order to design and synthesize materials that can precisely regulate the fate of MSCs,the relationship between the properties of materials and the fate of mesenchymal stem cells need to be clarified,in which the detection of the fate of mesenchymal stem cells plays an important role.In the past 30 years,a series of detection technologies have been developed to detect the fate of MSCs regulated by bioactive materials,among which high-throughput technology has shown great advantages due to its ability to detect large amounts of data at one time.In this review,the latest research progresses of detecting the fate of MSCs regulated by bone bioactive materials(BBMs)are systematically reviewed from traditional technology to high-throughput technology which is emphasized especially.Moreover,current problems and the future development direction of detection technologies of the MSCs fate regulated by BBMs are prospected.The aim of this review is to provide a detection technical framework for researchers to establish the relationship between the properties of BMMs and the fate of MSCs,so as to help researchers to design and synthesize BBMs better which can precisely regulate the fate of MSCs.展开更多
It has been well recognized that the modification of biomaterials with appropriate bioactive peptides could further enhance their functions.Especially,it has been shown that peptide-modified bone repair materials coul...It has been well recognized that the modification of biomaterials with appropriate bioactive peptides could further enhance their functions.Especially,it has been shown that peptide-modified bone repair materials could promote new bone formation more efficiently compared with conventional ones.The purpose of this article is to give a general review of recent studies on bioactive peptide-modified materials for bone tissue repair.Firstly,the main peptides for inducing bone regeneration and commonly used methods to prepare peptide-modified bone repair materials are introduced.Then,current in vitro and in vivo research progress of peptide-modified composites used as potential bone repair materials are reviewed and discussed.Generally speaking,the recent related studies have fully suggested that the modification of bone repair materials with osteogenicrelated peptides provide promising strategies for the development of bioactive materials and substrates for enhanced bone regeneration and the therapy of bone tissue diseases.Furthermore,we have proposed some research trends in the conclusion and perspectives part.展开更多
Bone defects are commonly caused by severe trauma,malignant tumors,or congenital diseases and remain among the toughest clinical problems faced by orthopedic surgeons,especially when of critical size.Biodegradable zin...Bone defects are commonly caused by severe trauma,malignant tumors,or congenital diseases and remain among the toughest clinical problems faced by orthopedic surgeons,especially when of critical size.Biodegradable zinc-based metals have recently gained popularity for their desirable biocompatibility,suitable degradation rate,and favorable osteogenesis-promoting properties.The biphasic activity of Sr promotes osteogenesis and inhibits osteoclastogenesis,which imparts Zn-Sr alloys with the ideal theoretical osteogenic properties.Herein,a biodegradable Zn-Sr binary alloy system was fabricated.The cytocompatibility and osteogenesis of the Zn-Sr alloys were significantly better than those of pure Zn in MC3T3-E1 cells.RNA-sequencing illustrated that the Zn-0.8Sr alloy promoted osteogenesis by activating the wnt/β-catenin,PI3K/Akt,and MAPK/Erk signaling pathways.Furthermore,rat femoral condyle defects were repaired using Zn-0.8Sr alloy scaffolds,with pure Ti as a control.The scaffold-bone integration and bone ingrowth confirmed the favorable in vivo repair properties of the Zn-Sr alloy,which was verified to offer satisfactory biosafety based on the hematoxylin-eosin(H&E)staining and ion concentration testing of important organs.The Zn-0.8Sr alloy was identified as an ideal bone repair material candidate,especially for application in critical-sized defects on load-bearing sites due to its favorable biocompatibility and osteogenic properties in vitro and in vivo.展开更多
It has been well recognized that the development and use of artificial materials with high osteogenic ability is one of the most promising means to replace bone grafting that has exhibited various negative effects.The...It has been well recognized that the development and use of artificial materials with high osteogenic ability is one of the most promising means to replace bone grafting that has exhibited various negative effects.The biomimetic features and unique physiochemical properties of nanomaterials play important roles in stimulating cellular functions and guiding tissue regeneration.But efficacy degree of some nanomaterials to promote specific tissue formation is still not clear.We hereby comparatively studied the osteogenic ability of our treated multiwalled carbon nanotubes(MCNTs)and the main inorganic mineral component of natural bone,nano-hydroxyapatite(nHA)in the same system,and tried to tell the related mechanism.In vitro culture of human adiposederived mesenchymal stem cells(HASCs)on the MCNTs and nHA demonstrated that although there was no significant difference in the cell adhesion amount between on the MCNTs and nHA,the cell attachment strength and proliferation on the MCNTs were better.Most importantly,the MCNTs could induce osteogenic differentiation of the HASCs better than the nHA,the possible mechanism of which was found to be that the MCNTs could activate Notch involved signaling pathways by concentrating more proteins,including specific bone-inducing ones.Moreover,the MCNTs could induce ectopic bone formation in vivo while the nHA could not,which might be because MCNTs could stimulate inducible cells in tissues to form inductive bone better than nHA by concentrating more proteins including specific bone-inducing ones secreted from M2 macrophages.Therefore,MCNTs might be more effective materials for accelerating bone formation even than nHA.展开更多
Objective: To explore the method to repair bone defect with bone-morphogenetic-protein loaded hydroxyapatite/collagen-poly(L-lactic acid) composite. Methods: 18 adult beagle dogs were randomly divided into 3 groups. I...Objective: To explore the method to repair bone defect with bone-morphogenetic-protein loaded hydroxyapatite/collagen-poly(L-lactic acid) composite. Methods: 18 adult beagle dogs were randomly divided into 3 groups. In Group A, bone-morphogenetic-protein (BMP) loaded hydroxyapatite/collagen-poly(L-lactic acid) (HAC-PLA) scaffold was implanted in a 2 cm diaphyseal defect in the radius. In Group B, unloaded pure HAC-PLA scaffold was implanted in the defects. No material was implanted in Group C (control group). The dogs were sacrificed 6 months postoperatively. Features of biocompatibility, biodegradability and osteoinduction were evaluated with histological, radiological examinations and bone mineral density (BMD) measurements. Results: In Group A, the radius defect healed after the treatment with BMP loaded HAC-PLA. BMD at the site of the defect was higher than that of the contralateral radius. Fibrous union developed in the animals of the control group. Conclusions: BMP not only promotes osteogenesis but also accelerates degradation of the biomaterials. Optimized design parameters of a three-dimensional porous biomaterial would give full scope to the role of BMP as an osteoinductive growth factor.展开更多
The objective of this study was to characterize the chemical and physical properties of bioactive ceramics prepared from an aqueous paste containing hydroxyapatite(HA)and beta tri-calcium phosphate(β-TCP).Prior to fo...The objective of this study was to characterize the chemical and physical properties of bioactive ceramics prepared from an aqueous paste containing hydroxyapatite(HA)and beta tri-calcium phosphate(β-TCP).Prior to formulating the paste,HA andβ-TCP were calcined at 800℃and 975℃(11 h),milled,and blended into 15%/85%HA/β-TCP volume-mixed paste.Fabricated cylindrical rods were subsequently sintered to 900℃,1100℃or 1250℃.The sintered specimens were characterized by helium pycnometry,X-ray diffraction(XRD),Fourier transform-infrared(FT-IR),and inductively coupled plasma(ICP)spectroscopy for evaluation of porosity,crystalline phase,functional-groups,and Ca:P ratio,respectively.Mechanical properties were assessed via 3-point bending and diametral compression.Qualitative microstructural evaluation using scanning electron microscopy(SEM)showed larger pores and a broader pore size distribution(PSD)for materials sintered at 900℃and 1100℃,whereas the 1250℃samples showed more uniform PSD.Porosity quantification showed significantly higher porosity for materials sintered to 900℃and 1250℃(p<0.05).XRD indicated substantial deviations from the 15%/85%HA/β-TCP formulation following sintering where lower amounts of HA were observed when sintering temperature was increased.Mechanical testing demonstrated significant differences between calcination temperatures and different sintering regimes(p<0.05).Variation in chemical composition and mechanical properties of bioactive ceramics were direct consequences of calcination and sintering.展开更多
基金Supported by National Natural Science Foundation of China (Grant No.51975496)National Key Research and Development Program (Grant No.2019YFB1704800)+2 种基金Hunan Provincial Innovative Province Construction Special Project of China (Grant No.2020GK2083)Fundamental Research Funds for the Central Universities of China (Grant No.20720200068)Jiangsu Key Laboratory of Precision and Micro-Manufacturing Technology。
文摘In recent years,the number of patients with orthopedic diseases such as cervical spondylosis has increased,resulting in an increase in the demand for orthopedic surgery.However,thermal necrosis and bone cracks caused by surgery severely restrict the development and progression of orthopedic surgery.For the material of cutting tool processing bone in bone surgery of drilling high temperature lead to cell death,easy to produce the problem such as crack cause secondary damage effects to restore,in this paper,a bionic drill was designed based on the micro-structure of the dung beetle's head and back.The microstructure configuration parameters were optimized by numerical analysis,and making use of the optical fiber laser marking machine preparation of bionic bit;through drilling test,the mathematical model of drilling temperature and crack generation based on micro-structure characteristic parameters was established by infrared thermal imaging technology and acoustic emission signal technology,and the cooling mechanism and crack suppression strategy were studied.The experimental results show that when the speed is 60 m/min,the cooling effects of the bionic bit T1 and T2 are 15.31%and 19.78%,respectively,and both kinds of bits show obvious crack suppression effect.The research in this paper provides a new idea for precision and efficient machining of bone materials,and the research results will help to improve the design and manufacturing technology and theoretical research level in the field of bone drilling tools.
基金This study was supported by the Natural Science Foundation of Guangxi Zhuang Autonomous Region （No. 0135044）.
文摘Objective： To evaluate the effect of autologous bone marrow mesenchymal stem cells （BMSCs） seeded bio-derived bone materials （BBM） combined with recombinant human bone morphogenetic protein-2 （rhBMP-2） in repairing defect of osteonecrosis of femoral head （ONFH）. Methods： Early-stage osteonecrosis in the left hip was induced in 36 adult New Zealand white rabbits （provided by the Animal Center of Guangxi Medical University, Nanning, China） after core decompression and delivery of liquid nitrogen into the femoral head. Then the animals were divided into three groups according to the type of implants for bone repair： 12 rabbits with nothing （Group Ⅰ, the blank control group）, 12 with BBM combined with rhBMP-2 （Group Ⅱ）, and 12 with BMSCs-seeded BBM combined with rhBMP-2 （Group Ⅲ）. At 4, 8, and 12 weeks after surgery, X-ray of the femoral head of every 4 rabbits in each group was taken, and then they were killed and the femoral heads were collected at each time point, respectively. Gross observation was made on the femoral heads. After hematoxylin and eosin staining, Lane-sandhu scores of X-ray and bone densitometry were calculated and the histomorphometric measurements were made for the new bone trabeculae. Results： At 12 weeks after surgery, two femoral heads collapsed in Group Ⅰ, but none in Group Ⅱ or Group Ⅲ. X-ray examination showed that the femoral heads in Group I had defect shadow or collapsed while those in Group II had a low density and those in Group III presented with a normal density. Histologically, the defects of femoral heads were primarily filled with no new bone but fibrous tissues in Group Ⅰ. In contrast, new bone regeneration and fibrous tissues occurred in Group II and only new bone regeneration occurrd in Group Ⅲ. Lane-sandhu scores of X-ray, bone mineral density and rate of new bone in trabecular area in Group Ⅲ were higher significantly than those of the other two groups. Conclusions： Our findings indicate a superior choice of repairing the experimental defect of OFH with BMSCsseeded BBM combined with rhBMP-2.
基金supported by the National Natural Science Foundation of China(11174060,11327405)the Ph.D.Programs Foundation of the Ministry of Education of China(20110071130004,20130071110020)+1 种基金the Science and Technology Support Program of Shanghai(13441901900)the Program for New Century Excellent Talents in University(NCET-10-0349)
文摘In this study, ultrasonic backscattering signals in cancellous bones were obtained by finite difference time domain （FDTD） simulations, and the effect of trabecular material properties on these signals was analyzed. The backscatter coefficient （BSC） and integrated backscatter coefficient （IBC） were numerically investigated for varying trabecular bone material properties, including density, Lame coefficients, viscosities, and resistance coefficients. The results show that the BSC is a complex function of trabecular bone density, and the IBC increases as density increases. The BSC and IBC increase with the first and second Lame coefficients. While not very sensitive to the second viscosity of the trabeculae, the BSC and IBC decrease as the first viscosity and resistance coefficients increase. The results demonstrate that, in addition to bone mineral density （BMD） and microarchitecture, trabecular material properties significantly influence ultrasonic backseattering signals in cancellous bones. This research furthers the understanding of ultrasonic backscattering in cancellous bones and the characterization of cancellous bone status.
文摘BACKGROUND Tibial plateau fractures often require structural support for metaphyseal defects created during articular reduction.While autologous bone grafting has been utilized as the gold standard,bone substitutes offer advantages including reduced donor site morbidity.Our meta-analysis evaluated the comparative efficacy of these approaches across clinical and operative outcomes.AIM To conduct a systematic review and meta-analysis of randomized controlled trials comparing autologous bone grafts with bone substitutes for tibial plateau fractures.METHODS We conducted a systematic review and meta-analysis of randomized controlled trials comparing autologous bone grafts with bone substitutes for tibial plateau fractures.Primary outcomes included joint depression,secondary collapse rate,operative time,blood loss,and infection rate.Subgroup analyses were performed by fracture complexity,geographic region,and methodological factors.In addition to that,we also developed a combined outcome score integrating structural,procedural,and complication domains.RESULTS Seven randomized controlled trials with 424 patients(296 bone substitute,128 autograft)were included.No significant differences in joint depression or secondary collapse were observed across fracture complexity categories.Geographic variations were evident,with Western studies showing significantly higher risk of secondary collapse with autografts(risk ratio=1.45,P value=0.02).Both Western and Asian studies have demonstrated significantly reduced blood loss with bone substitutes(70-90 mL less),while operative time reduction was more significant in the Asian studies(23.65 vs 8.00 minutes,P value=0.04 for subgroup difference).The combined outcome score(standardized effect size-0.2481)favored bone substitutes,primarily due to procedural advantages.CONCLUSION Bone substitutes provide similar structural outcomes to autologous bone grafts while having better procedural advantages in tibial plateau fracture management.These findings support bone substitutes as a viable option across fracture patterns.Future studies should focus on specific bone substitute formulations and cost-effectiveness analyses.
基金National Natural Science Foundation of China(No.82060347)Postgraduate innovation research project of Hainan Medical College(No.HYYS2020-38)。
文摘Objective:To prepare a bone repair material with certain mechanical strength and biological activity,this paper used calcium sulfate hemihydrate(CSH)powder compounded with calcium hydroxide(Ca(OH)2)powder to prepare a bone repair scaffold material for physicochemical property characterization and testing.Methods:The physical and chemical properties and characterization of the dried and cured bone repair materials were determined by Fourier infrared spectroscopy(FT-IR),X-ray diffraction(XRD),and scanning electron microscopy;Universal material testing machine to determine the mechanical and mechanical strength of composite materials.Results:XRD showed that the structure of the composite material phase at 5%concentration was calcium sulfate hemihydrate and calcium hydroxide after hydration.The FT-IR and XRD analyses were consistent.Scanning electron microscopy(SEM)results showed that calcium hydroxide was uniformly dispersed in the hemihydrate calcium sulfate material.0%,1%,5%,and 10%specimen groups had compressive strengths of 3.86±3.1,5.27±1.28,8.22±0.96,and 14.4±3.28 MPa.10%addition of calcium hydroxide significantly improved the mechanical strength of the composites,but also reduced the the porosity of the material.Conclusion:With the addition of calcium hydroxide,the CSH-Ca(OH)2 composite was improved in terms of mechanical material and is expected to be a new type of bone repair material.
基金financially supported by the National Nat-ural Science Foundation of China(Nos.32071341,82202741,52003302,31430030,51973021,32201111,and 52202358)the Chinese Postdoctoral Science Foundation(Nos.2021M703710 and 2021M691464)+1 种基金the Guangdong Basic and Applied Basic Re-search Foundation(Nos.2021A1515111040,2019A1515110841 and 2019A1515011935)the Beijing Municipal Health Commis-sion(Nos.BMHC-20216 and PXM 2020_026275_000002)。
文摘Tissue engineering aims to offer large-scale replacement of damaged organs using implants with the com-bination of cells,growth factors and scaffolds.However,the intra/peri-implant region is exposed to se-vere hypoxic stress and oxidative stress during the early stage of implantation with bone graft materials,which endangers the survival,proliferation and differentiation of seed cells within the implants as well as the host cells surrounding the implants.If the bone graft material could spontaneously and intelligently regulate the hypoxic stress and oxidative stress to a moderate level,it will facilitate the vascularization of the implants and the rapid regeneration of the bone tissue.In this review,we will first introduce the signaling pathways of cellular response under hypoxic stress and oxidative stress,then present the clas-sical material designs and examples in response to hypoxic stress and oxidative stress.And finally,we will address the important role of epigenetic mechanisms in the regulation of hypoxic stress and oxida-tive stress and describe the potential applications and prospective smart bone graft materials based on novel epigenetic factors against hypoxic stress and oxidative stress in bone repair.The main content of this review is summarized in the following graphical abstract.
基金the Ministry of Science and Innovation of Spain for financial support(Nos.RTI2018098075-B-C21 and RTI2018-098075-B-C22)the EU through the European Regional Development Funds(No.MINECO-FEDER,EU)+1 种基金Generalitat de Catalunya(No.2017SGR-1165)the KTT Excellence Program,funded by the European Union through the European Regional Development Fund(EDF),the Government of Catalonia and the UPC。
文摘One of the biggest challenges in the biocompatibility of implantable metals is the prevention of the stress shielding effect,which is related to the coupling of the bone-metal mechanical properties.This stress shielding phenomenon provokes bone resorption and the consequent adverse effects on prosthesis fixation.However,it can be inhibited by adapting the stiffness of the implant material.Since the use of titanium(Ti)porous structures is a great alternative not only to inhibit this effect but also to improve the osteointegration of orthopedic and dental implants,a brief description of the techniques used for their manufacturing and a review of the current commercialized implants produced from porous Ti assemblies are compiled in this work.As powder metallurgy(PM)with space holder(SH)is a powerful technology used to produce porous Ti structures,it is here discussed its potential for the fabrication of medical devices from the perspectives of both design and manufacture.The most important parameters of the technique such as the size and shape of the initial metallic particles,the SH and binder type of materials,the compaction pressure of the green form,and in the sintering stage,the temperature,atmosphere,and time are reviewed according to the bibliography reported.Furthermore,the importance of the porosity and its types together with the influence of the mentioned parameters in the final porosity and,consequently,in the ultimate mechanical properties of the structure are discussed.Finally,a few examples of the PM-SH application for the manufacturing of orthopedic implants are presented.
基金supported by the National major research and invention programme of the thirteenth of China(no.2016YFC1102000)the Dalian Science and Technology Innovation Fund Project(no.2018J11CY030).
文摘Porous silicon carbide(SiC)has a specific biomorphous microstructure similar to the trabecular microstructure of human bone.Compared with that of bioactive ceramics,such as calcium phosphate,SiC does not induce spontaneous interface bonding to living bone.In this study,bioactive tantalum(Ta)metal deposited on porous SiC scaffolds by chemical vapour deposition was investigated to accelerate osseointegration and improve the bonding to bones.Scanning electron microscopy indicated that the Ta coating evenly covered the entire scaffold structure.Energy-dispersive spectroscopy and X-ray diffraction analysis showed that the coating consisted of Ta phases.The bonding strength between the Ta coating and the SiC substrate is 88.4MPa.The yield strength of porous SiC with a Ta coating(pTa)was 45.862.9MPa,the compressive strength was 61.463.2MPa and the elasticmodulus was4.8GPa.When MG-63 human osteoblasts were co-cultured with pTa,osteoblasts showed good adhesion and spreading on the surface of the pTa and its porous structure,which showed that it has excellent bioactivity and cyto-compatibility.To further study the osseointegration properties of pTa.PTa and porous titanium(pTi)were implanted into the femoral neck of goats for 12weeks,respectively.The Van-Gieson staining of histological sections results that the pTa group had better osseointegration than the pTi group.These results indicate that coating bioactive Ta metal on porous SiC scaffolds could be a potential material for bone substitutes.
基金Acknowledgements This work was supported by the National Basic Research Program of China （Grant No. 2012CB822102）, the National Major Scientific and Technological Special Project forSignificant New Drags Development＂ （Grant No. 2012ZX09502001-005）, the National High Technology Research and Development Program of China （Grant No. 2012AA021500）, Shandong Province Science and Technology Development Project （Grant No. 2014GSFI 18113）, Shandong Province Natural Science Foundation （Grant No. ZR2012EMM008）, and the Fundamental Research Funds of Shandong University （Grant No. 2015JC004）.
文摘Minimally invasive injectable self-setting materials are useful for bone repairs and for bone tissue regeneration in situ. Due to the potential advantages of these materials, such as causing minimal tissue injury, nearly no influence on blood supply, easy operation and negligible postoperative pain, they have shown great promises and successes in clinical applications. It has been proposed that an ideal injectable bone repair material should have features similar to that of natural bones, in terms of both the microstructure and the composition, so that it not only provides adequate stimulus to facilitate cell adhesion, proliferation and differentiation but also offers a satisfactory biological environment for new bone to grow at the implantation site. This article reviews the properties and applications of injectable bone repair materials, including those that are based on natural and synthetic polymers, calcium phosphate, calcium phosphate/ polymer composites and calcium sulfate, to orthopedics and bone tissue repairs, as well as the progress made in biomimetic fabrication of injectable bone repair materials.
基金supported by the National Key Research and Development Program of China(2016YFB0700802)Natural Sciences Foundation of China(31670991)+3 种基金Major projects of the National Social Science Funding(17ZDA019)the National Natural Science Foundation of China(81671829)Intergovernmental cooperation in science and technology(2016YFE0125300)Tsinghua University Initiative Scientific Research Program(2017THZWYX07).
文摘The fate of mesenchymal stem cells(MSCs)is regulated by biological,physical and chemical signals.Developments in biotechnology and materials science promoted the occurrence of bioactive materials which can provide physical and chemical signals for MSCs to regulate their fate.In order to design and synthesize materials that can precisely regulate the fate of MSCs,the relationship between the properties of materials and the fate of mesenchymal stem cells need to be clarified,in which the detection of the fate of mesenchymal stem cells plays an important role.In the past 30 years,a series of detection technologies have been developed to detect the fate of MSCs regulated by bioactive materials,among which high-throughput technology has shown great advantages due to its ability to detect large amounts of data at one time.In this review,the latest research progresses of detecting the fate of MSCs regulated by bone bioactive materials(BBMs)are systematically reviewed from traditional technology to high-throughput technology which is emphasized especially.Moreover,current problems and the future development direction of detection technologies of the MSCs fate regulated by BBMs are prospected.The aim of this review is to provide a detection technical framework for researchers to establish the relationship between the properties of BMMs and the fate of MSCs,so as to help researchers to design and synthesize BBMs better which can precisely regulate the fate of MSCs.
基金National Natural Science Foundation of China(Nos.31370959,11421202 and 61227902)Fok Ying Tung Education Foundation(No.141039)+1 种基金Beijing Nova Programme Interdisciplinary Cooperation Project(No.xxjc201616)Key Laboratory of Advanced Materials of Ministry of Education of China(Tsinghua University),International Joint Research Center of Aerospace Biotechnology and Medical Engineering,Ministry of Science and Technology of China,and the 111 Project(No.B13003).
文摘It has been well recognized that the modification of biomaterials with appropriate bioactive peptides could further enhance their functions.Especially,it has been shown that peptide-modified bone repair materials could promote new bone formation more efficiently compared with conventional ones.The purpose of this article is to give a general review of recent studies on bioactive peptide-modified materials for bone tissue repair.Firstly,the main peptides for inducing bone regeneration and commonly used methods to prepare peptide-modified bone repair materials are introduced.Then,current in vitro and in vivo research progress of peptide-modified composites used as potential bone repair materials are reviewed and discussed.Generally speaking,the recent related studies have fully suggested that the modification of bone repair materials with osteogenicrelated peptides provide promising strategies for the development of bioactive materials and substrates for enhanced bone regeneration and the therapy of bone tissue diseases.Furthermore,we have proposed some research trends in the conclusion and perspectives part.
基金This work was supported by the National Natural Science Foundation of China[Grant No.51931001].
文摘Bone defects are commonly caused by severe trauma,malignant tumors,or congenital diseases and remain among the toughest clinical problems faced by orthopedic surgeons,especially when of critical size.Biodegradable zinc-based metals have recently gained popularity for their desirable biocompatibility,suitable degradation rate,and favorable osteogenesis-promoting properties.The biphasic activity of Sr promotes osteogenesis and inhibits osteoclastogenesis,which imparts Zn-Sr alloys with the ideal theoretical osteogenic properties.Herein,a biodegradable Zn-Sr binary alloy system was fabricated.The cytocompatibility and osteogenesis of the Zn-Sr alloys were significantly better than those of pure Zn in MC3T3-E1 cells.RNA-sequencing illustrated that the Zn-0.8Sr alloy promoted osteogenesis by activating the wnt/β-catenin,PI3K/Akt,and MAPK/Erk signaling pathways.Furthermore,rat femoral condyle defects were repaired using Zn-0.8Sr alloy scaffolds,with pure Ti as a control.The scaffold-bone integration and bone ingrowth confirmed the favorable in vivo repair properties of the Zn-Sr alloy,which was verified to offer satisfactory biosafety based on the hematoxylin-eosin(H&E)staining and ion concentration testing of important organs.The Zn-0.8Sr alloy was identified as an ideal bone repair material candidate,especially for application in critical-sized defects on load-bearing sites due to its favorable biocompatibility and osteogenic properties in vitro and in vivo.
基金The authors acknowledge the financial supports from the National Natural Science Foundation of China(No.31771042)Fok Ying Tung Education Foundation(No.141039)+1 种基金State Key Laboratory of New Ceramic and Fine Processing Tsinghua University,Fund of Key Laboratory of Advanced Materials of Ministry of Education(No.2020AML10)International Joint Research Center of Aerospace Biotechnology and Medical Engineering,Ministry of Science and Technology of China,and the 111 Project(No.B13003).
文摘It has been well recognized that the development and use of artificial materials with high osteogenic ability is one of the most promising means to replace bone grafting that has exhibited various negative effects.The biomimetic features and unique physiochemical properties of nanomaterials play important roles in stimulating cellular functions and guiding tissue regeneration.But efficacy degree of some nanomaterials to promote specific tissue formation is still not clear.We hereby comparatively studied the osteogenic ability of our treated multiwalled carbon nanotubes(MCNTs)and the main inorganic mineral component of natural bone,nano-hydroxyapatite(nHA)in the same system,and tried to tell the related mechanism.In vitro culture of human adiposederived mesenchymal stem cells(HASCs)on the MCNTs and nHA demonstrated that although there was no significant difference in the cell adhesion amount between on the MCNTs and nHA,the cell attachment strength and proliferation on the MCNTs were better.Most importantly,the MCNTs could induce osteogenic differentiation of the HASCs better than the nHA,the possible mechanism of which was found to be that the MCNTs could activate Notch involved signaling pathways by concentrating more proteins,including specific bone-inducing ones.Moreover,the MCNTs could induce ectopic bone formation in vivo while the nHA could not,which might be because MCNTs could stimulate inducible cells in tissues to form inductive bone better than nHA by concentrating more proteins including specific bone-inducing ones secreted from M2 macrophages.Therefore,MCNTs might be more effective materials for accelerating bone formation even than nHA.
文摘Objective: To explore the method to repair bone defect with bone-morphogenetic-protein loaded hydroxyapatite/collagen-poly(L-lactic acid) composite. Methods: 18 adult beagle dogs were randomly divided into 3 groups. In Group A, bone-morphogenetic-protein (BMP) loaded hydroxyapatite/collagen-poly(L-lactic acid) (HAC-PLA) scaffold was implanted in a 2 cm diaphyseal defect in the radius. In Group B, unloaded pure HAC-PLA scaffold was implanted in the defects. No material was implanted in Group C (control group). The dogs were sacrificed 6 months postoperatively. Features of biocompatibility, biodegradability and osteoinduction were evaluated with histological, radiological examinations and bone mineral density (BMD) measurements. Results: In Group A, the radius defect healed after the treatment with BMP loaded HAC-PLA. BMD at the site of the defect was higher than that of the contralateral radius. Fibrous union developed in the animals of the control group. Conclusions: BMP not only promotes osteogenesis but also accelerates degradation of the biomaterials. Optimized design parameters of a three-dimensional porous biomaterial would give full scope to the role of BMP as an osteoinductive growth factor.
文摘The objective of this study was to characterize the chemical and physical properties of bioactive ceramics prepared from an aqueous paste containing hydroxyapatite(HA)and beta tri-calcium phosphate(β-TCP).Prior to formulating the paste,HA andβ-TCP were calcined at 800℃and 975℃(11 h),milled,and blended into 15%/85%HA/β-TCP volume-mixed paste.Fabricated cylindrical rods were subsequently sintered to 900℃,1100℃or 1250℃.The sintered specimens were characterized by helium pycnometry,X-ray diffraction(XRD),Fourier transform-infrared(FT-IR),and inductively coupled plasma(ICP)spectroscopy for evaluation of porosity,crystalline phase,functional-groups,and Ca:P ratio,respectively.Mechanical properties were assessed via 3-point bending and diametral compression.Qualitative microstructural evaluation using scanning electron microscopy(SEM)showed larger pores and a broader pore size distribution(PSD)for materials sintered at 900℃and 1100℃,whereas the 1250℃samples showed more uniform PSD.Porosity quantification showed significantly higher porosity for materials sintered to 900℃and 1250℃(p<0.05).XRD indicated substantial deviations from the 15%/85%HA/β-TCP formulation following sintering where lower amounts of HA were observed when sintering temperature was increased.Mechanical testing demonstrated significant differences between calcination temperatures and different sintering regimes(p<0.05).Variation in chemical composition and mechanical properties of bioactive ceramics were direct consequences of calcination and sintering.
