Infectious bone defects represent a substantial challenge in clinical practice,necessitating the deployment of advanced therapeutic strategies.This study presents a treatment modality that merges a mild photothermal t...Infectious bone defects represent a substantial challenge in clinical practice,necessitating the deployment of advanced therapeutic strategies.This study presents a treatment modality that merges a mild photothermal therapy hydrogel with a pulsed drug delivery mechanism.The system is predicated on a hydrogel matrix that is thermally responsive,characteristic of bone defect sites,facilitating controlled and site-specific drug release.The cornerstone of this system is the incorporation of mild photothermal nanoparticles,which are activated within the temperature range of 40–43°C,thereby enhancing the precision and efficacy of drug delivery.Our findings demonstrate that the photothermal response significantly augments the localized delivery of therapeutic agents,mitigating systemic side effects and bolstering efficacy at the defect site.The synchronized pulsed release,cooperated with mild photothermal therapy,effectively addresses infection control,and promotes bone regeneration.This approach signifies a considerable advancement in the management of infectious bone defects,offering an effective and patient-centric alternative to traditional methods.Our research endeavors to extend its applicability to a wider spectrum of tissue regeneration scenarios,underscoring its transformative potential in the realm of regenerative medicine.展开更多
The regeneration of infected bone defects is still challenging and time-consuming,due to the adverse osteogenic microenvironment caused by bacterial contamination and pronounced ischemia.Biodegradable magnesium(Mg)-ba...The regeneration of infected bone defects is still challenging and time-consuming,due to the adverse osteogenic microenvironment caused by bacterial contamination and pronounced ischemia.Biodegradable magnesium(Mg)-based alloys are desirable for orthopedic implants due to the mechanical properties approximating those of human bone and the released Mg^(2+)ions essential to osteogenic activity.However,the fast and uncontrolled self-degradation of Mg alloy,along with the inadequate antimicrobial activity,limit their strength in the osteogenic microenvironment.Inspired by the structural and physiological characteristics of“fish scales,”two-dimensional(2D)nanomaterials,black phosphorus(BP)and graphene oxide(GO),were assembled together under the action of pulsed electric field.The bionic 2D layered BP/GO nano-coating was constructed for infection resistance,osteogenic microenvironment optimization,and biodegradation control.In the early stage of implantation,it exerted a photothermal effect to ablate bacterial biofilms and avoid contaminating the microenvironment.The blocking effect of the“nano fish scales”-2D material superposition regulated the degradation of implants.In the later stage,it attracted the migration of vascular endothelial cells(VECs)and released phosphate slowly for in situ mineralization to create the microenvironment favoring vascularized bone formation.It is indicated that the enhancement of microtubule deacetylation and cytoskeletal reorganization played a key role in the effect of VEC migration and angiogenesis.This study provided a promising bionic strategy for creating osteogenic microenvironments that match the sequential healing process of infected bone defects.展开更多
As the global population ages,osteoporotic bone fractures leading to bone defects are increasingly becoming a significant challenge in the field of public health.Treating this disease faces many challenges,especially ...As the global population ages,osteoporotic bone fractures leading to bone defects are increasingly becoming a significant challenge in the field of public health.Treating this disease faces many challenges,especially in the context of an imbalance between osteoblast and osteoclast activities.Therefore,the development of new biomaterials has become the key.This article reviews various design strategies and their advantages and disadvantages for biomaterials aimed at osteoporotic bone defects.Overall,current research progress indicates that innovative design,functionalization,and targeting of materials can significantly enhance bone regeneration under osteoporotic conditions.By comprehensively considering biocompatibility,mechanical properties,and bioactivity,these biomaterials can be further optimized,offering a range of choices and strategies for the repair of osteoporotic bone defects.展开更多
Large bone defects in load-bearing bone can result from tumor resection,osteomyelitis,trauma,and other factors.Although bone has the intrinsic potential to self-repair and regenerate,the repair of large bone defects w...Large bone defects in load-bearing bone can result from tumor resection,osteomyelitis,trauma,and other factors.Although bone has the intrinsic potential to self-repair and regenerate,the repair of large bone defects which exceed a certain critical size remains a substantial clinical challenge.Traditionally,repair methods involve using autologous or allogeneic bone tissue to replace the lost bone tissue at defect sites,and autogenous bone grafting remains the“gold standard”treatment.However,the application of traditional bone grafts is limited by drawbacks such as the quantity of extractable bone,donor-site morbidities,and the risk of rejection.In recent years,the clinical demand for alternatives to traditional bone grafts has promoted the development of novel bone-grafting substitutes.In addition to osteoconductivity and osteoinductivity,optimal mechanical properties have recently been the focus of efforts to improve the treatment success of novel bone-grafting alternatives in load-bearing bone defects,but most biomaterial synthetic scaffolds cannot provide sufficient mechanical strength.A fundamental challenge is to find an appropriate balance between mechanical and tissue-regeneration requirements.In this review,the use of traditional bone grafts in load-bearing bone defects,as well as their advantages and disadvantages,is summarized and reviewed.Furthermore,we highlight recent development strategies for novel bone grafts appropriate for load-bearing bone defects based on substance,structural,and functional bionics to provide ideas and directions for future research.展开更多
The technology of three dimensional(3D) printing,also known as additive manufacturing,is a cuttingedge type of fabrication method that utilizes a computer-aided design platform and employs layer-bylayer stacking to co...The technology of three dimensional(3D) printing,also known as additive manufacturing,is a cuttingedge type of fabrication method that utilizes a computer-aided design platform and employs layer-bylayer stacking to construct objects with exceptional flexibility.Due to its capacity to produce a substantial quantity of products within a short period of time,3D printing has emerged as one of the most significant manufacturing technology.Over the past two decades,remarkable advancements have been made in the application of 3D printing technology in the realm of bone tissue engineering.This review presents an innovative and systematic discussion on the potential application of 3D printing technology in bone tissue engineering,particularly in the treatment of infected bone defects.It comprehensively evaluates the materials utilized in 3D printing,highlights the interplay between cells and bone regeneration,and addresses and resolves challenges associated with current 3D printing technology.These challenges include material selection,fabrication of intricate 3D structures,integration of different cell types,streamlining design processes and material selection procedures,enhancing the clinical translational potential of 3D printing technology,and ultimately exploring future applications of four dimensional(4D) printing technology.The 3D printing technology has demonstrated significant potential in the synthesis of bone substitutes,offering consistent mechanical properties and ease of use.It has found extensive applications in personalized implant customization,prosthetic limb manufacturing,surgical tool production,tissue engineering,biological modeling,and cell diagnostics.Simultaneously,3D bioprinting provides an effective solution to address the issue of organ donor shortage.However,challenges still exist in material selection,management of structural complexity,integration of different cell types,and construction of functionally mature tissues.With advancements in multi-material printing techniques as well as bioprinting and 4D printing technologies emerging on the horizon;3D printing holds immense prospects for revolutionizing the means by which infectious bone defects are repaired.展开更多
Objective:To investigate the clinical effect of the guided bone regeneration(GBR)technique combined with temporary bridgework-guided gingival contouring in treating upper anterior tooth loss with labial bone defects.M...Objective:To investigate the clinical effect of the guided bone regeneration(GBR)technique combined with temporary bridgework-guided gingival contouring in treating upper anterior tooth loss with labial bone defects.Methods:From July 2023 to April 2024,80 patients with upper anterior tooth loss and labial bone defects were admitted to the hospital and selected as evaluation samples.They were divided into an observation group(n=40)and a control group(n=40)using a numerical table lottery scheme.The control group received treatment with the GBR technique,while the observation group received treatment with the GBR technique combined with temporary bridges to guide gingival contouring.The two groups were compared in terms of clinical red aesthetic scores(PES),labial alveolar bone density,labial bone wall thickness,gingival papillae,gingival margin levels,and patient satisfaction.Results:The PES scores of patients in the observation group were higher than those in the control group after surgery(P<0.05).The bone density of the labial alveolar bone and the thickness of the labial bone wall in the observation group were higher than those in the control group.The levels of gingival papillae and gingival margins were lower in the observation group after surgery(P<0.05).Additionally,patient satisfaction in the observation group was higher than in the control group(P<0.05).Conclusion:The GBR technique combined with temporary bridge-guided gingival contouring for treating upper anterior tooth loss with labial bone defects can improve the aesthetic effect of gingival soft tissue,increase alveolar bone density and the thickness of the labial bone wall,and enhance patient satisfaction.This approach is suitable for widespread application in healthcare institutions.展开更多
Additive manufacturing(AM)has revolutionized the design and manufacturing of patient-specific,three-dimensional(3D),complex porous structures known as scaffolds for tissue engineering applications.The use of advanced ...Additive manufacturing(AM)has revolutionized the design and manufacturing of patient-specific,three-dimensional(3D),complex porous structures known as scaffolds for tissue engineering applications.The use of advanced image acquisition techniques,image processing,and computer-aided design methods has enabled the precise design and additive manufacturing of anatomically correct and patient-specific implants and scaffolds.However,these sophisticated techniques can be timeconsuming,labor-intensive,and expensive.Moreover,the necessary imaging and manufacturing equipment may not be readily available when urgent treatment is needed for trauma patients.In this study,a novel design and AM methods are proposed for the development of modular and customizable scaffold blocks that can be adapted to fit the bone defect area of a patient.These modular scaffold blocks can be combined to quickly form any patient-specific scaffold directly from two-dimensional(2D)medical images when the surgeon lacks access to a 3D printer or cannot wait for lengthy 3D imaging,modeling,and 3D printing during surgery.The proposed method begins with developing a bone surface-modeling algorithm that reconstructs a model of the patient’s bone from 2D medical image measurements without the need for expensive 3D medical imaging or segmentation.This algorithm can generate both patient-specific and average bone models.Additionally,a biomimetic continuous path planning method is developed for the additive manufacturing of scaffolds,allowing porous scaffold blocks with the desired biomechanical properties to be manufactured directly from 2D data or images.The algorithms are implemented,and the designed scaffold blocks are 3D printed using an extrusion-based AM process.Guidelines and instructions are also provided to assist surgeons in assembling scaffold blocks for the self-repair of patient-specific large bone defects.展开更多
To investigate the feasibility of implanting the biocomposite of calcium phosphate cement(CPC)/polylactic acid-polyglycolic acid(PLGA) into animals for bone defects repairing,the biocomposite of CPC/PLGA was prepared ...To investigate the feasibility of implanting the biocomposite of calcium phosphate cement(CPC)/polylactic acid-polyglycolic acid(PLGA) into animals for bone defects repairing,the biocomposite of CPC/PLGA was prepared and its setting time,compressive strength,elastic modulus,pH values,phase composition of the samples,degradability and biocompatibility in vitro were tested.The above-mentioned composite implanted with bone marrow stromal cells was used to repair defects of the radius in rabbits.Osteogenesis was histomorphologically observed by using an electron-microscope.The results show that compared with the CPC,the physical and chemical properties of CPC/PLGA composite have some differences in which CPC/PLGA composite has better biological properties.The CPC/PLGA composite combined with seed cells is superior to the control in terms of the amount of new bones formed after CPC/PLGA composite is implanted into the rabbits,as well as the speed of repairing bone defects.The results suggest that the constructed CPC/PLGA composite basically meets the requirements of tissue engineering scaffold materials and that the CPC/PLGA composite implanted with bone marrow stromal cells may be a new artificial bone material for repairing bone defects because it can promote the growth of bone tissues.展开更多
TGF-β is a multifunctional cytokine that regulates many aspects of cellular function, including periosteal mesenchymal cell proliferation, differentiation. This experiment is to study its effects on bone defect repai...TGF-β is a multifunctional cytokine that regulates many aspects of cellular function, including periosteal mesenchymal cell proliferation, differentiation. This experiment is to study its effects on bone defect repair. A rabbit radial bone defect model was used to evaluate the effect of TGF-β, which was extracted and purified from bovine blood platelets, on the healing of a large segmental osteoperiosteal defect. A 1. 5-centimeter segmental defect was created in the mid-upper part of the radial shaft of adult rabbits. The defect was filled with implant containing TGF-β that consisted of carrier and bovine TGF-β. Limbs served as controls received carrier alone. The defectswere examined radiographically and histologically at 4, 8,12 , 16 and 20 weeks after implantation. The results showed that in TGF-β implant group . the defect areas at 12 weeks post operation were bridged by uniform new bone and the cut ends of cortex could not be seen;while in control group, the defects remained clear. Only a small amount of new bone formed as a cap on the cut bone ends. In the experimental group, new lamellar and woven bone formed in continuity with the cut ends of the cortex. An early medullar canal appears to be forming and contained normal-appearancing marrow elements; while the control group displayed entirely fibrous tissue within the defect site. Remnants of the cancellous bone carrier were observed in the control specimen. These data demonstrate that exogenous TGF-β initiate osteogenesis and stimulate the bone defects repair in animal model.展开更多
Objective:To report the clinical outcome of repairing massive bone defects biologically in limbs by homeochronous using structural bone allografts with intramedullary vascularized fibular autografts. Methods: From Jan...Objective:To report the clinical outcome of repairing massive bone defects biologically in limbs by homeochronous using structural bone allografts with intramedullary vascularized fibular autografts. Methods: From January 2001 to December 2005, large bone defects in 19 patients (11 men and 8 women, aged 6 to 35 years) were repaired by structural bone allografts with intramedullary vascularized fibular autografts in the homeochronous period. The range of the length of bone defects was 11 to 25 cm (mean 17.6 cm), length of vascularized free fibular was 15 to 29 cm (mean 19.2 cm), length of massive bone allografts was 11 to 24 cm (mean 17.1 cm). Location of massive bone defects was in humerus(n=1), in femur(n=9) and in tibia(n=9), respectively. Results: After 9 to 69 months (mean 38.2 months) follow-up, wounds of donor and recipient sites were healed inⅠstage, monitoring-flaps were alive, eject reaction of massive bone allografts were slight, no complications in donor limbs. Fifteen patients had the evidence of radiographic union 3 to 6 months after surgery, 3 cases united 8 months later, and the remained one case of malignant synovioma in distal femur recurred and amputated the leg 2.5 months, postoperatively. Five patients had been removed internal fixation, complete bone unions were found one year postoperatively. None of massive bone allografts were absorbed or collapsed at last follow-up. Conclusion: The homeochronous usage of structural bone allograft with an intramedullary vascularized fibular autograft can biologically obtain a structure with the immediate mechanical strength of the allograft, a potential result of revascularization through the vascularized fibula, and accelerate bone union not only between fibular autograft and the host but also between massive bone allograft and the host.展开更多
BACKGROUND Ilizarov non-free bone plasty is a method of distraction osteogenesis using the Ilizarov apparatus for external fixation which originated in Russia and was disseminated across the world. It has been used in...BACKGROUND Ilizarov non-free bone plasty is a method of distraction osteogenesis using the Ilizarov apparatus for external fixation which originated in Russia and was disseminated across the world. It has been used in long bone defect and nonunion management along with free vascularized grafting and induced membrane technique. However, the shortcomings and problems of these methods still remain the issues which restrict their overall use.AIM To study the recent available literature on the role of Ilizarov non-free bone plasty in long bone defect and nonunion management, its problems and the solutions to these problems in order to achieve better treatment outcomes.METHODS Three databases(Pub Med, Scopus, and Web of Science) were searched for literature sources on distraction osteogenesis, free vascularized grafting and induced membrane technique used in long bone defect and nonunion treatment within a five-year period(2015-2019). Full-text clinical articles in the English language were selected for analysis only if they contained treatment results,complications and described large patient samples(not less than ten cases for congenital, post-tumor resection cases or rare conditions, and more than 20 cases for the rest). Case reports were excluded.RESULTS Fifty full-text articles and reviews on distraction osteogenesis were chosen.Thirty-five clinical studies containing large series of patients treated with this method and problems with its outcome were analyzed. It was found that distraction osteogenesis techniques provide treatment for segmental bone defects and nonunion of the lower extremity in many clinical situations, especially in complex problems. The Ilizarov techniques treat the triad of problems simultaneously(bone loss, soft-tissue loss and infection). Management of tibial defects mostly utilizes the Ilizarov circular fixator. Monolateral fixators are preferable in the femur. The use of a ring fixator is recommended in patients with an infected tibial bone gap of more than 6 cm. High rates of successful treatment were reported by the authors that ranged from 77% to 100% and depended on the pathology and the type of Ilizarov technique used. Hybrid fixation and autogenous grafting are the most applicable solutions to avoid after-frame regenerate fracture or deformity and docking site nonunion.CONCLUSION The role of Ilizarov non-free bone plasty has not lost its significance in the treatment of segmental bone defects despite the shortcomings and treatment problems encountered.展开更多
Objective：To study the possibility of natural hydroxyapatite/chitosan composite on repairing bone defects. Methods：We developed a natural hydroxyapatite/chitosan composite that could be molded into any desired shape...Objective：To study the possibility of natural hydroxyapatite/chitosan composite on repairing bone defects. Methods：We developed a natural hydroxyapatite/chitosan composite that could be molded into any desired shape. The powder component consists of natural hydroxyapatite, which is epurated from bone of pigs. The liquid component consists of malic acid and chitosan. Operations were performed on the left tibias of 15 white rabbits to create two square bone defects. One of the defects was reconstructed with the composite, while the other was not repaired and used as a blank control. Three of the animals were killed at the end of 2 weeks, 4 weeks, 8 weeks, 12 weeks and 16 weeks respectively and implants were evaluated anatomically and histologically. Results：No apparent rejection reaction was found, except for a mild inflammatory infiltration observed 2 weeks after surgery. Fibrous tissue became thinner 2 -8 weeks after surgery and bony connections were detected 12 weeks after surgery. The new bone was the same as the recipient bone by the 16th postoperative week. Conclusion：The hydroxyapatite/chitosan composite has good biocompatibility and osteoconduction. It is a potential repairing material for clinical application.展开更多
The stability parameters of implants （ITV, ISQ ＆ PTV） according to different sizes of controlled bone defects made in implant osteotomies were analyzed and the correlation among the three kinds of implant stability...The stability parameters of implants （ITV, ISQ ＆ PTV） according to different sizes of controlled bone defects made in implant osteotomies were analyzed and the correlation among the three kinds of implant stability parameters was tested in this study. 45 tapped screw-type dental implants were inserted in three types of implant osteotomies made in 8 fresh-frozen pig femoral bones： Typel - without coronal bone defect, Type2 - with 3 mm coronal bone defects, and Type3 - with 6 mm coronal bone defects. The insertion torque values, ISQ ＆ PTV of implants were measured and analyzed statistically. It is concluded that the circumferential coronal bone defects statistically influence the primary stability of implants; ITV, ISQ and PTV are suitable and available to detect the peri-implant coronal bone defects in 3 mm increments, and ITV and PTV are more sensitive to coronal cortical bone loss. There was a strong correlation between ITV and ISQ.展开更多
In order to evaluate the efficacy of low intensity ultrasound and tissue engineering technique to repair segmental bone defects, the rabbit models of 1.5-cm long rabbit radial segmental osteoperiosteum defects were es...In order to evaluate the efficacy of low intensity ultrasound and tissue engineering technique to repair segmental bone defects, the rabbit models of 1.5-cm long rabbit radial segmental osteoperiosteum defects were established and randomly divided into 2 groups. All defects were implanted with the composite of calcium phosphate cement and bone mesenchymal stem cells, and ad- ditionally those in experimental group were subjected to low intensity ultrasound exposure, while those in control group to sham exposure. The animals were killed on the postoperative week 4, 8 and 12 respectively, and specimens were harvested. By using radiography and the methods of biomechanics, histomorphology and bone density detection, new bone formation and material degradation were observed. The results showed that with the prolongation of time after operation, serum alkaline phosphatase （AKP） levels in both groups were gradually increased, especially in experimental group, reached the peak at 6th week （experimental group： 1,26 mmol/L; control group： 0.58 mmol/L）, suggesting the new bone formation in both two group, but the amount of new bone formation was greater and bone repairing capacity stronger in experimental group than in control group. On the 4th week in experimental group, chondrocytes differentiated into woven bone, and on the 12th week, remodeling of new lamellar bone and absorption of the composite material were observed. The mechanical strength of composite material and new born density in experimental group were significantly higher than in control group, indicating that low intensity ultrasound could not only effectively increase the formation of new bone, but also accelerate the calcification of new bone. It was concluded that low intensity ultrasound could evidently accelerate the healing of bone defects repaired by bone tissue engineering.展开更多
Irregular craniofacial bone defects caused by craniofacial fractures always result in craniofacial bone and contour asymmetry and should therefore be reconstructed.Polyetheretherketone(PEEK)is an ideal substitute for ...Irregular craniofacial bone defects caused by craniofacial fractures always result in craniofacial bone and contour asymmetry and should therefore be reconstructed.Polyetheretherketone(PEEK)is an ideal substitute for autologous bone grafts and has been widely used in craniofacial bone defect reconstruction.The precise design of custom-made PEEK implants is particularly important to optimise reconstruction.Herein,the workflow and principles for the design and manufacture of PEEK implants are summarised,and a protocol for the precise design of an irregular craniofacial bone defect PEEK implant is presented.According to the method and principles,the design flow was efficient and could be standardised,and design errors could be avoided as much as possible.展开更多
Objective: To systematically evaluate the clinical efficacy and safety of Masquelet technology and Llizarov group technology in the treatment of infectious bone defects by meta-analysis. Methods: The computer searched...Objective: To systematically evaluate the clinical efficacy and safety of Masquelet technology and Llizarov group technology in the treatment of infectious bone defects by meta-analysis. Methods: The computer searched China Knowledge Network (CNKI), Wanfang, VIP, Chinese Biomedical Literature Database (CBM), Pubmed, Medline, Cochrane Llibrary databases. The retrieval time was from the time of the establishment of the database to January 2020. According to the inclusion and exclusion criteria, randomized controlled trials on the treatment of infectious bone defects using Masquelet technology and Llizarov technology were collected, and the retrieved literature was independently screened, evaluated, and data extracted by two researchers, and then RevMan5.3 software was used so for meta-analysis. Results: A total of 10 RCT documents were included, with a total of 496 patients, including 242 in the Masquelet group and 254 in the Llizarov group. The results of the meta-analysis showed that: in terms of bone defect healing time, total weight bearing time, treatment cost, and complication rate, the Masquelet group was significantly different from the Llizarov group, and the Masquelet group was better than the Llizarov group (P <0.05);In terms of knee joint Lowa score and SF-36 score, Masquelet group has significant differences compared with Llizarov group, Llizarov group is better than Masquelet group (P <0.05);in excellent rate, number of operations, ankle Lowa score, infection control rate In terms of excellent rate of affected limb function, there was no significant difference between Masquelet group and Llizarov group (P> 0.05). Conclusion:Compared with Llizarov technology, Masquelet technology has obvious advantages in the treatment of infectious bone defects in terms of bone defect healing time, total weight-bearing time, treatment cost, and complication rate. In terms of scoring, it has advantages over Masquelet technology, but in terms of excellent treatment rate, number of operations, and ankle lowa score. In terms of infection control rate and excellent function of affected limbs, there was no significant difference between Masquelet technology and Llizarov technology,However, due to the low quality of the included studies and the small sample size, the exact efficacy still needs to be confirmed by higher quality RCT studies.展开更多
Repair of osteoporotic bone defects(OBD)remains a clinical challenge due to dysregulated bone homeostasis,characterized by impaired osteogenesis and excessive osteoclast activity.While drug-loaded 3D-printed scaffolds...Repair of osteoporotic bone defects(OBD)remains a clinical challenge due to dysregulated bone homeostasis,characterized by impaired osteogenesis and excessive osteoclast activity.While drug-loaded 3D-printed scaffolds hold great potential in the restoration of bone homeostasis for enhanced OBD repair,achieving the controlled release and targeted delivery of drugs in a 3D-printed scaffold is still unmet.Herein,we developed an electrostatic encapsulation strategy to motivate 3D-printed polyelectrolyte scaffolds(APS@P)with bone-targeting liposome formulation of salvianolic acid B(SAB-BTL).Benefiting from this strategy,SAB,an unstable and untargetable plant-derived osteogenic compound,was effectively encapsulated in APS@P,demonstrating stable and precise delivery with improved therapeutic efficacy.Owing to SAB-mediated bone homeostasis,APS@P significantly promoted angiogenesis and new bone formation while suppressing bone resorption,resulting in a significant 146%increase in bone mass and improved microstructure compared to the OBD group.It was confirmed that the encapsulation of SAB into APS@P could promote the osteogenic differentiation of MSCs by stimulating Tph2/Wnt/β-catenin signaling axis,coupled with the stimulation of type H angiogenesis and the suppression of RANKL-mediate bone resorption,thereby enhance OBD repair.This study provides a universal platform for enhancing the bioactivity of tissue-engineered scaffolds,offering an effective solution for the efficient regeneration of osteoporotic bone.展开更多
The impact of orthopedic scaffolds on bone defect healing,particularly the late-stage bone remodeling process,is pivotal for the therapeutic outcome.This study applies fadditively manufactured scaffolds composed of hy...The impact of orthopedic scaffolds on bone defect healing,particularly the late-stage bone remodeling process,is pivotal for the therapeutic outcome.This study applies fadditively manufactured scaffolds composed of hydroxyapatite-doped poly(lactide-co-glycolide)-b-poly(ethylene glycol)-b-poly(lactide-co-glycolide)(HAPELGA)with varying properties to treat rat calvarial defects,elucidating their significant role in bone remodeling by modulating physiological responses.We engineered two scaffolds with different polylactic acid(PLA)to polyglycolic acid(PGA)ratio(9/1 and 18/1)to vary in hydrophobicity,degradation rate,mechanical properties,and structural stability.These variations influenced physiological responses,including osteogenesis,angiogen-esis,and immune reactions,thereby guiding bone remodeling.Our findings show that the HA-PELGA(18/1)scaffold,with a slower degradation rate,supported bulk bone formation due to a stable microenvironment.Conversely,the HA-PELGA(9/1)scaffold,with a faster degradation rate and more active interfaces,facilitated the formation of a thin bone layer and higher bone infiltration.This study demonstrates these degradable scaffolds help to promote bone healing and reveals how scaffold properties influence the bone remodeling process,offering a potential strategy to optimize scaffold design aiming at late-stage bone defect healing.展开更多
Addressing the challenge of eliminating bacteria and stimulating osteogenesis in infectious bone defects,where cells and bacteria coexist within the microenvironment,presents a significant hurdle.In this study,a strat...Addressing the challenge of eliminating bacteria and stimulating osteogenesis in infectious bone defects,where cells and bacteria coexist within the microenvironment,presents a significant hurdle.In this study,a strategy of targeting bacteria is proposed to address this challenge.For this purpose,a methacrylated gelatin composite hydrogel containing zinc ion and D-type cysteine-modified polydopamine nanoparticles(PZC)is developed.The D-cysteine,involved in the metabolism of the bacterial peptidoglycan chain,allows PZC to specifically target bacteria,exhibiting a form of“disguise strategy”.Through the targeting effect,this composite hydrogel can selectively kill bacteria and promote osteogenesis combing photothermal therapy with Zn^(2+)release,which showcases spatial controllability.Moreover,the antibacterial ability will be further improved after Near-infrared light irradiation.The multifunctional hydrogel containing Zn^(2+)modified nanoparticles can also promote osteogenic differentiation of bone marrow stem cells.Animal studies have revealed that the multifunctional hydrogel can inhibit bacteria growth and promote repair of infectious bone defects in rats.Findings from this study imply that endowing the nanoparticles with bacteria-targeting function can precisely control the events in cells and bacteria in the complex microenvironment,which can provide insights for the treatment of complex diseases with antibacterial requirements.展开更多
基金supported by the National Natural Science Foundation of China(32171354,82222015,82171001)The National Key Research and Development Program of China2023YFC2413600Research Funding from West China School/Hospital of Stomatology,Sichuan University(No.RCDWIS2023-1).
文摘Infectious bone defects represent a substantial challenge in clinical practice,necessitating the deployment of advanced therapeutic strategies.This study presents a treatment modality that merges a mild photothermal therapy hydrogel with a pulsed drug delivery mechanism.The system is predicated on a hydrogel matrix that is thermally responsive,characteristic of bone defect sites,facilitating controlled and site-specific drug release.The cornerstone of this system is the incorporation of mild photothermal nanoparticles,which are activated within the temperature range of 40–43°C,thereby enhancing the precision and efficacy of drug delivery.Our findings demonstrate that the photothermal response significantly augments the localized delivery of therapeutic agents,mitigating systemic side effects and bolstering efficacy at the defect site.The synchronized pulsed release,cooperated with mild photothermal therapy,effectively addresses infection control,and promotes bone regeneration.This approach signifies a considerable advancement in the management of infectious bone defects,offering an effective and patient-centric alternative to traditional methods.Our research endeavors to extend its applicability to a wider spectrum of tissue regeneration scenarios,underscoring its transformative potential in the realm of regenerative medicine.
基金supported by the National Natural Science Foundation of China[81801007]the Traditional Chinese Medicine Bureau of Guangdong Province[20242062]+2 种基金the Major of Basic and Applied Basic Research Project of Guangzhou City[202201011601]the Science and Cultivation Foundation of Stomatological Hospital of Southern Medical University[PY2021016]the Guangdong Province Clinical Teaching Base Teaching Reform Research Project[2023JD054].
文摘The regeneration of infected bone defects is still challenging and time-consuming,due to the adverse osteogenic microenvironment caused by bacterial contamination and pronounced ischemia.Biodegradable magnesium(Mg)-based alloys are desirable for orthopedic implants due to the mechanical properties approximating those of human bone and the released Mg^(2+)ions essential to osteogenic activity.However,the fast and uncontrolled self-degradation of Mg alloy,along with the inadequate antimicrobial activity,limit their strength in the osteogenic microenvironment.Inspired by the structural and physiological characteristics of“fish scales,”two-dimensional(2D)nanomaterials,black phosphorus(BP)and graphene oxide(GO),were assembled together under the action of pulsed electric field.The bionic 2D layered BP/GO nano-coating was constructed for infection resistance,osteogenic microenvironment optimization,and biodegradation control.In the early stage of implantation,it exerted a photothermal effect to ablate bacterial biofilms and avoid contaminating the microenvironment.The blocking effect of the“nano fish scales”-2D material superposition regulated the degradation of implants.In the later stage,it attracted the migration of vascular endothelial cells(VECs)and released phosphate slowly for in situ mineralization to create the microenvironment favoring vascularized bone formation.It is indicated that the enhancement of microtubule deacetylation and cytoskeletal reorganization played a key role in the effect of VEC migration and angiogenesis.This study provided a promising bionic strategy for creating osteogenic microenvironments that match the sequential healing process of infected bone defects.
基金supported by the National Natural Science Foundation of China(Nos.82160419 and 82302772)Guizhou Basic Research Project(No.ZK[2023]General 201)。
文摘As the global population ages,osteoporotic bone fractures leading to bone defects are increasingly becoming a significant challenge in the field of public health.Treating this disease faces many challenges,especially in the context of an imbalance between osteoblast and osteoclast activities.Therefore,the development of new biomaterials has become the key.This article reviews various design strategies and their advantages and disadvantages for biomaterials aimed at osteoporotic bone defects.Overall,current research progress indicates that innovative design,functionalization,and targeting of materials can significantly enhance bone regeneration under osteoporotic conditions.By comprehensively considering biocompatibility,mechanical properties,and bioactivity,these biomaterials can be further optimized,offering a range of choices and strategies for the repair of osteoporotic bone defects.
基金supported by the National Natural Science Foundation of China(No.82202450).
文摘Large bone defects in load-bearing bone can result from tumor resection,osteomyelitis,trauma,and other factors.Although bone has the intrinsic potential to self-repair and regenerate,the repair of large bone defects which exceed a certain critical size remains a substantial clinical challenge.Traditionally,repair methods involve using autologous or allogeneic bone tissue to replace the lost bone tissue at defect sites,and autogenous bone grafting remains the“gold standard”treatment.However,the application of traditional bone grafts is limited by drawbacks such as the quantity of extractable bone,donor-site morbidities,and the risk of rejection.In recent years,the clinical demand for alternatives to traditional bone grafts has promoted the development of novel bone-grafting substitutes.In addition to osteoconductivity and osteoinductivity,optimal mechanical properties have recently been the focus of efforts to improve the treatment success of novel bone-grafting alternatives in load-bearing bone defects,but most biomaterial synthetic scaffolds cannot provide sufficient mechanical strength.A fundamental challenge is to find an appropriate balance between mechanical and tissue-regeneration requirements.In this review,the use of traditional bone grafts in load-bearing bone defects,as well as their advantages and disadvantages,is summarized and reviewed.Furthermore,we highlight recent development strategies for novel bone grafts appropriate for load-bearing bone defects based on substance,structural,and functional bionics to provide ideas and directions for future research.
基金supported by the National Natural Science Fund of China(Nos.82202726,82370929)the National Clinical Research Center for Geriatrics,West China Hospital,Sichuan University(No.Z20192013)+5 种基金Key research and development project of Sichuan Science and Technology Department(No.2023YFG0219)"Zeroto One" Innovation Research Project of Sichuan University(No.2022SCUH0014)Frontiers Medical Center,Tianfu Jincheng Laboratory Foundation(No.TFJC2023010001)Sichuan Science and Technology Program(No.2022NSFSC0002)Sichuan Province Youth Science and Technology Innovation Team(No.2022JDTD0021)Research and Develop Program,West China Hospital of Stomatology Sichuan University(Nos.RD03202302,RCDWJS2024-1)。
文摘The technology of three dimensional(3D) printing,also known as additive manufacturing,is a cuttingedge type of fabrication method that utilizes a computer-aided design platform and employs layer-bylayer stacking to construct objects with exceptional flexibility.Due to its capacity to produce a substantial quantity of products within a short period of time,3D printing has emerged as one of the most significant manufacturing technology.Over the past two decades,remarkable advancements have been made in the application of 3D printing technology in the realm of bone tissue engineering.This review presents an innovative and systematic discussion on the potential application of 3D printing technology in bone tissue engineering,particularly in the treatment of infected bone defects.It comprehensively evaluates the materials utilized in 3D printing,highlights the interplay between cells and bone regeneration,and addresses and resolves challenges associated with current 3D printing technology.These challenges include material selection,fabrication of intricate 3D structures,integration of different cell types,streamlining design processes and material selection procedures,enhancing the clinical translational potential of 3D printing technology,and ultimately exploring future applications of four dimensional(4D) printing technology.The 3D printing technology has demonstrated significant potential in the synthesis of bone substitutes,offering consistent mechanical properties and ease of use.It has found extensive applications in personalized implant customization,prosthetic limb manufacturing,surgical tool production,tissue engineering,biological modeling,and cell diagnostics.Simultaneously,3D bioprinting provides an effective solution to address the issue of organ donor shortage.However,challenges still exist in material selection,management of structural complexity,integration of different cell types,and construction of functionally mature tissues.With advancements in multi-material printing techniques as well as bioprinting and 4D printing technologies emerging on the horizon;3D printing holds immense prospects for revolutionizing the means by which infectious bone defects are repaired.
文摘Objective:To investigate the clinical effect of the guided bone regeneration(GBR)technique combined with temporary bridgework-guided gingival contouring in treating upper anterior tooth loss with labial bone defects.Methods:From July 2023 to April 2024,80 patients with upper anterior tooth loss and labial bone defects were admitted to the hospital and selected as evaluation samples.They were divided into an observation group(n=40)and a control group(n=40)using a numerical table lottery scheme.The control group received treatment with the GBR technique,while the observation group received treatment with the GBR technique combined with temporary bridges to guide gingival contouring.The two groups were compared in terms of clinical red aesthetic scores(PES),labial alveolar bone density,labial bone wall thickness,gingival papillae,gingival margin levels,and patient satisfaction.Results:The PES scores of patients in the observation group were higher than those in the control group after surgery(P<0.05).The bone density of the labial alveolar bone and the thickness of the labial bone wall in the observation group were higher than those in the control group.The levels of gingival papillae and gingival margins were lower in the observation group after surgery(P<0.05).Additionally,patient satisfaction in the observation group was higher than in the control group(P<0.05).Conclusion:The GBR technique combined with temporary bridge-guided gingival contouring for treating upper anterior tooth loss with labial bone defects can improve the aesthetic effect of gingival soft tissue,increase alveolar bone density and the thickness of the labial bone wall,and enhance patient satisfaction.This approach is suitable for widespread application in healthcare institutions.
文摘Additive manufacturing(AM)has revolutionized the design and manufacturing of patient-specific,three-dimensional(3D),complex porous structures known as scaffolds for tissue engineering applications.The use of advanced image acquisition techniques,image processing,and computer-aided design methods has enabled the precise design and additive manufacturing of anatomically correct and patient-specific implants and scaffolds.However,these sophisticated techniques can be timeconsuming,labor-intensive,and expensive.Moreover,the necessary imaging and manufacturing equipment may not be readily available when urgent treatment is needed for trauma patients.In this study,a novel design and AM methods are proposed for the development of modular and customizable scaffold blocks that can be adapted to fit the bone defect area of a patient.These modular scaffold blocks can be combined to quickly form any patient-specific scaffold directly from two-dimensional(2D)medical images when the surgeon lacks access to a 3D printer or cannot wait for lengthy 3D imaging,modeling,and 3D printing during surgery.The proposed method begins with developing a bone surface-modeling algorithm that reconstructs a model of the patient’s bone from 2D medical image measurements without the need for expensive 3D medical imaging or segmentation.This algorithm can generate both patient-specific and average bone models.Additionally,a biomimetic continuous path planning method is developed for the additive manufacturing of scaffolds,allowing porous scaffold blocks with the desired biomechanical properties to be manufactured directly from 2D data or images.The algorithms are implemented,and the designed scaffold blocks are 3D printed using an extrusion-based AM process.Guidelines and instructions are also provided to assist surgeons in assembling scaffold blocks for the self-repair of patient-specific large bone defects.
基金Projects(30370412, 30670558) supported by the National Natural Science Foundation of China
文摘To investigate the feasibility of implanting the biocomposite of calcium phosphate cement(CPC)/polylactic acid-polyglycolic acid(PLGA) into animals for bone defects repairing,the biocomposite of CPC/PLGA was prepared and its setting time,compressive strength,elastic modulus,pH values,phase composition of the samples,degradability and biocompatibility in vitro were tested.The above-mentioned composite implanted with bone marrow stromal cells was used to repair defects of the radius in rabbits.Osteogenesis was histomorphologically observed by using an electron-microscope.The results show that compared with the CPC,the physical and chemical properties of CPC/PLGA composite have some differences in which CPC/PLGA composite has better biological properties.The CPC/PLGA composite combined with seed cells is superior to the control in terms of the amount of new bones formed after CPC/PLGA composite is implanted into the rabbits,as well as the speed of repairing bone defects.The results suggest that the constructed CPC/PLGA composite basically meets the requirements of tissue engineering scaffold materials and that the CPC/PLGA composite implanted with bone marrow stromal cells may be a new artificial bone material for repairing bone defects because it can promote the growth of bone tissues.
文摘TGF-β is a multifunctional cytokine that regulates many aspects of cellular function, including periosteal mesenchymal cell proliferation, differentiation. This experiment is to study its effects on bone defect repair. A rabbit radial bone defect model was used to evaluate the effect of TGF-β, which was extracted and purified from bovine blood platelets, on the healing of a large segmental osteoperiosteal defect. A 1. 5-centimeter segmental defect was created in the mid-upper part of the radial shaft of adult rabbits. The defect was filled with implant containing TGF-β that consisted of carrier and bovine TGF-β. Limbs served as controls received carrier alone. The defectswere examined radiographically and histologically at 4, 8,12 , 16 and 20 weeks after implantation. The results showed that in TGF-β implant group . the defect areas at 12 weeks post operation were bridged by uniform new bone and the cut ends of cortex could not be seen;while in control group, the defects remained clear. Only a small amount of new bone formed as a cap on the cut bone ends. In the experimental group, new lamellar and woven bone formed in continuity with the cut ends of the cortex. An early medullar canal appears to be forming and contained normal-appearancing marrow elements; while the control group displayed entirely fibrous tissue within the defect site. Remnants of the cancellous bone carrier were observed in the control specimen. These data demonstrate that exogenous TGF-β initiate osteogenesis and stimulate the bone defects repair in animal model.
文摘Objective:To report the clinical outcome of repairing massive bone defects biologically in limbs by homeochronous using structural bone allografts with intramedullary vascularized fibular autografts. Methods: From January 2001 to December 2005, large bone defects in 19 patients (11 men and 8 women, aged 6 to 35 years) were repaired by structural bone allografts with intramedullary vascularized fibular autografts in the homeochronous period. The range of the length of bone defects was 11 to 25 cm (mean 17.6 cm), length of vascularized free fibular was 15 to 29 cm (mean 19.2 cm), length of massive bone allografts was 11 to 24 cm (mean 17.1 cm). Location of massive bone defects was in humerus(n=1), in femur(n=9) and in tibia(n=9), respectively. Results: After 9 to 69 months (mean 38.2 months) follow-up, wounds of donor and recipient sites were healed inⅠstage, monitoring-flaps were alive, eject reaction of massive bone allografts were slight, no complications in donor limbs. Fifteen patients had the evidence of radiographic union 3 to 6 months after surgery, 3 cases united 8 months later, and the remained one case of malignant synovioma in distal femur recurred and amputated the leg 2.5 months, postoperatively. Five patients had been removed internal fixation, complete bone unions were found one year postoperatively. None of massive bone allografts were absorbed or collapsed at last follow-up. Conclusion: The homeochronous usage of structural bone allograft with an intramedullary vascularized fibular autograft can biologically obtain a structure with the immediate mechanical strength of the allograft, a potential result of revascularization through the vascularized fibula, and accelerate bone union not only between fibular autograft and the host but also between massive bone allograft and the host.
文摘BACKGROUND Ilizarov non-free bone plasty is a method of distraction osteogenesis using the Ilizarov apparatus for external fixation which originated in Russia and was disseminated across the world. It has been used in long bone defect and nonunion management along with free vascularized grafting and induced membrane technique. However, the shortcomings and problems of these methods still remain the issues which restrict their overall use.AIM To study the recent available literature on the role of Ilizarov non-free bone plasty in long bone defect and nonunion management, its problems and the solutions to these problems in order to achieve better treatment outcomes.METHODS Three databases(Pub Med, Scopus, and Web of Science) were searched for literature sources on distraction osteogenesis, free vascularized grafting and induced membrane technique used in long bone defect and nonunion treatment within a five-year period(2015-2019). Full-text clinical articles in the English language were selected for analysis only if they contained treatment results,complications and described large patient samples(not less than ten cases for congenital, post-tumor resection cases or rare conditions, and more than 20 cases for the rest). Case reports were excluded.RESULTS Fifty full-text articles and reviews on distraction osteogenesis were chosen.Thirty-five clinical studies containing large series of patients treated with this method and problems with its outcome were analyzed. It was found that distraction osteogenesis techniques provide treatment for segmental bone defects and nonunion of the lower extremity in many clinical situations, especially in complex problems. The Ilizarov techniques treat the triad of problems simultaneously(bone loss, soft-tissue loss and infection). Management of tibial defects mostly utilizes the Ilizarov circular fixator. Monolateral fixators are preferable in the femur. The use of a ring fixator is recommended in patients with an infected tibial bone gap of more than 6 cm. High rates of successful treatment were reported by the authors that ranged from 77% to 100% and depended on the pathology and the type of Ilizarov technique used. Hybrid fixation and autogenous grafting are the most applicable solutions to avoid after-frame regenerate fracture or deformity and docking site nonunion.CONCLUSION The role of Ilizarov non-free bone plasty has not lost its significance in the treatment of segmental bone defects despite the shortcomings and treatment problems encountered.
基金supported by Science and Technology Projects Fund of Nanjing Medical University(NY0522)
文摘Objective：To study the possibility of natural hydroxyapatite/chitosan composite on repairing bone defects. Methods：We developed a natural hydroxyapatite/chitosan composite that could be molded into any desired shape. The powder component consists of natural hydroxyapatite, which is epurated from bone of pigs. The liquid component consists of malic acid and chitosan. Operations were performed on the left tibias of 15 white rabbits to create two square bone defects. One of the defects was reconstructed with the composite, while the other was not repaired and used as a blank control. Three of the animals were killed at the end of 2 weeks, 4 weeks, 8 weeks, 12 weeks and 16 weeks respectively and implants were evaluated anatomically and histologically. Results：No apparent rejection reaction was found, except for a mild inflammatory infiltration observed 2 weeks after surgery. Fibrous tissue became thinner 2 -8 weeks after surgery and bony connections were detected 12 weeks after surgery. The new bone was the same as the recipient bone by the 16th postoperative week. Conclusion：The hydroxyapatite/chitosan composite has good biocompatibility and osteoconduction. It is a potential repairing material for clinical application.
基金Sponsored by the Scientific Research Foundation for the Returned Overseas Chinese Scholars,Ministry of Education,China
文摘The stability parameters of implants （ITV, ISQ ＆ PTV） according to different sizes of controlled bone defects made in implant osteotomies were analyzed and the correlation among the three kinds of implant stability parameters was tested in this study. 45 tapped screw-type dental implants were inserted in three types of implant osteotomies made in 8 fresh-frozen pig femoral bones： Typel - without coronal bone defect, Type2 - with 3 mm coronal bone defects, and Type3 - with 6 mm coronal bone defects. The insertion torque values, ISQ ＆ PTV of implants were measured and analyzed statistically. It is concluded that the circumferential coronal bone defects statistically influence the primary stability of implants; ITV, ISQ and PTV are suitable and available to detect the peri-implant coronal bone defects in 3 mm increments, and ITV and PTV are more sensitive to coronal cortical bone loss. There was a strong correlation between ITV and ISQ.
文摘In order to evaluate the efficacy of low intensity ultrasound and tissue engineering technique to repair segmental bone defects, the rabbit models of 1.5-cm long rabbit radial segmental osteoperiosteum defects were established and randomly divided into 2 groups. All defects were implanted with the composite of calcium phosphate cement and bone mesenchymal stem cells, and ad- ditionally those in experimental group were subjected to low intensity ultrasound exposure, while those in control group to sham exposure. The animals were killed on the postoperative week 4, 8 and 12 respectively, and specimens were harvested. By using radiography and the methods of biomechanics, histomorphology and bone density detection, new bone formation and material degradation were observed. The results showed that with the prolongation of time after operation, serum alkaline phosphatase （AKP） levels in both groups were gradually increased, especially in experimental group, reached the peak at 6th week （experimental group： 1,26 mmol/L; control group： 0.58 mmol/L）, suggesting the new bone formation in both two group, but the amount of new bone formation was greater and bone repairing capacity stronger in experimental group than in control group. On the 4th week in experimental group, chondrocytes differentiated into woven bone, and on the 12th week, remodeling of new lamellar bone and absorption of the composite material were observed. The mechanical strength of composite material and new born density in experimental group were significantly higher than in control group, indicating that low intensity ultrasound could not only effectively increase the formation of new bone, but also accelerate the calcification of new bone. It was concluded that low intensity ultrasound could evidently accelerate the healing of bone defects repaired by bone tissue engineering.
基金the Program of Shanghai Municipal Commission of Health and Family Planning(No.20194Y0033)。
文摘Irregular craniofacial bone defects caused by craniofacial fractures always result in craniofacial bone and contour asymmetry and should therefore be reconstructed.Polyetheretherketone(PEEK)is an ideal substitute for autologous bone grafts and has been widely used in craniofacial bone defect reconstruction.The precise design of custom-made PEEK implants is particularly important to optimise reconstruction.Herein,the workflow and principles for the design and manufacture of PEEK implants are summarised,and a protocol for the precise design of an irregular craniofacial bone defect PEEK implant is presented.According to the method and principles,the design flow was efficient and could be standardised,and design errors could be avoided as much as possible.
基金The Science and Technology Project of Henan Province (182102310487)
文摘Objective: To systematically evaluate the clinical efficacy and safety of Masquelet technology and Llizarov group technology in the treatment of infectious bone defects by meta-analysis. Methods: The computer searched China Knowledge Network (CNKI), Wanfang, VIP, Chinese Biomedical Literature Database (CBM), Pubmed, Medline, Cochrane Llibrary databases. The retrieval time was from the time of the establishment of the database to January 2020. According to the inclusion and exclusion criteria, randomized controlled trials on the treatment of infectious bone defects using Masquelet technology and Llizarov technology were collected, and the retrieved literature was independently screened, evaluated, and data extracted by two researchers, and then RevMan5.3 software was used so for meta-analysis. Results: A total of 10 RCT documents were included, with a total of 496 patients, including 242 in the Masquelet group and 254 in the Llizarov group. The results of the meta-analysis showed that: in terms of bone defect healing time, total weight bearing time, treatment cost, and complication rate, the Masquelet group was significantly different from the Llizarov group, and the Masquelet group was better than the Llizarov group (P <0.05);In terms of knee joint Lowa score and SF-36 score, Masquelet group has significant differences compared with Llizarov group, Llizarov group is better than Masquelet group (P <0.05);in excellent rate, number of operations, ankle Lowa score, infection control rate In terms of excellent rate of affected limb function, there was no significant difference between Masquelet group and Llizarov group (P> 0.05). Conclusion:Compared with Llizarov technology, Masquelet technology has obvious advantages in the treatment of infectious bone defects in terms of bone defect healing time, total weight-bearing time, treatment cost, and complication rate. In terms of scoring, it has advantages over Masquelet technology, but in terms of excellent treatment rate, number of operations, and ankle lowa score. In terms of infection control rate and excellent function of affected limbs, there was no significant difference between Masquelet technology and Llizarov technology,However, due to the low quality of the included studies and the small sample size, the exact efficacy still needs to be confirmed by higher quality RCT studies.
基金funded by grants from National Key R&D Program(No.2022YFB3804403)the National Natural Science Foundation of China(No.92468106)+6 种基金Guangdong Basic and Applied Basic Research Foundation(Nos.2024B1515040018,2022A1515220166,2023A1515011091,2022A1515140138)the Science and Technology Foundation of Zhanjiang(Nos.2022A01099,2022A01163,2022A01170)the Shenzhen Medical Research Fund(No.A2303016)the Shenzhen Science and Technology Program(No.JSGGKQTD20210831174330015,JCYJ20210324113001005)Disci-pline construction project of Guangdong Medical University(Nos.4SG23002G and CLP2021B012)the Discipline Construction Fund of Central People’s Hospital of Zhanjiang(No.2022A09)Guangdong medical university research fund(No.FYZM001).
文摘Repair of osteoporotic bone defects(OBD)remains a clinical challenge due to dysregulated bone homeostasis,characterized by impaired osteogenesis and excessive osteoclast activity.While drug-loaded 3D-printed scaffolds hold great potential in the restoration of bone homeostasis for enhanced OBD repair,achieving the controlled release and targeted delivery of drugs in a 3D-printed scaffold is still unmet.Herein,we developed an electrostatic encapsulation strategy to motivate 3D-printed polyelectrolyte scaffolds(APS@P)with bone-targeting liposome formulation of salvianolic acid B(SAB-BTL).Benefiting from this strategy,SAB,an unstable and untargetable plant-derived osteogenic compound,was effectively encapsulated in APS@P,demonstrating stable and precise delivery with improved therapeutic efficacy.Owing to SAB-mediated bone homeostasis,APS@P significantly promoted angiogenesis and new bone formation while suppressing bone resorption,resulting in a significant 146%increase in bone mass and improved microstructure compared to the OBD group.It was confirmed that the encapsulation of SAB into APS@P could promote the osteogenic differentiation of MSCs by stimulating Tph2/Wnt/β-catenin signaling axis,coupled with the stimulation of type H angiogenesis and the suppression of RANKL-mediate bone resorption,thereby enhance OBD repair.This study provides a universal platform for enhancing the bioactivity of tissue-engineered scaffolds,offering an effective solution for the efficient regeneration of osteoporotic bone.
文摘The impact of orthopedic scaffolds on bone defect healing,particularly the late-stage bone remodeling process,is pivotal for the therapeutic outcome.This study applies fadditively manufactured scaffolds composed of hydroxyapatite-doped poly(lactide-co-glycolide)-b-poly(ethylene glycol)-b-poly(lactide-co-glycolide)(HAPELGA)with varying properties to treat rat calvarial defects,elucidating their significant role in bone remodeling by modulating physiological responses.We engineered two scaffolds with different polylactic acid(PLA)to polyglycolic acid(PGA)ratio(9/1 and 18/1)to vary in hydrophobicity,degradation rate,mechanical properties,and structural stability.These variations influenced physiological responses,including osteogenesis,angiogen-esis,and immune reactions,thereby guiding bone remodeling.Our findings show that the HA-PELGA(18/1)scaffold,with a slower degradation rate,supported bulk bone formation due to a stable microenvironment.Conversely,the HA-PELGA(9/1)scaffold,with a faster degradation rate and more active interfaces,facilitated the formation of a thin bone layer and higher bone infiltration.This study demonstrates these degradable scaffolds help to promote bone healing and reveals how scaffold properties influence the bone remodeling process,offering a potential strategy to optimize scaffold design aiming at late-stage bone defect healing.
基金funding provided for this study by the National Key R&D Program of China(2023YFB3810200,2023YFB3810201)the National Natural Science Foundation of China(81925027,32171350,32471410)+8 种基金International Cooperation Project of Ningbo City(2023H013)Jiangsu Basic Research Program(Natural Science Foundation)(BK20240020)Medical and Health Science and Technology Innovation Project of Suzhou(SKY2022105)Jiangsu Province Science and Technology Plan Special Fund(BE2022730)Postdoctoral Fellowship Program of CPSF(BX20230253,GZB20230505)Basic cutting-edge innovation cross project of Suzhou Medical College of Soochow University(YXY2302010,YXY2304046,YXY2304053)the China Postdoctoral Science Foundation under Grant Number 2023TQ0235Science and Technology Development Project of Suzhou(SGC202379,SZS2023043)the Priority Academic Program Development(PAPD)of Jiangsu Higher Education Institutions.
文摘Addressing the challenge of eliminating bacteria and stimulating osteogenesis in infectious bone defects,where cells and bacteria coexist within the microenvironment,presents a significant hurdle.In this study,a strategy of targeting bacteria is proposed to address this challenge.For this purpose,a methacrylated gelatin composite hydrogel containing zinc ion and D-type cysteine-modified polydopamine nanoparticles(PZC)is developed.The D-cysteine,involved in the metabolism of the bacterial peptidoglycan chain,allows PZC to specifically target bacteria,exhibiting a form of“disguise strategy”.Through the targeting effect,this composite hydrogel can selectively kill bacteria and promote osteogenesis combing photothermal therapy with Zn^(2+)release,which showcases spatial controllability.Moreover,the antibacterial ability will be further improved after Near-infrared light irradiation.The multifunctional hydrogel containing Zn^(2+)modified nanoparticles can also promote osteogenic differentiation of bone marrow stem cells.Animal studies have revealed that the multifunctional hydrogel can inhibit bacteria growth and promote repair of infectious bone defects in rats.Findings from this study imply that endowing the nanoparticles with bacteria-targeting function can precisely control the events in cells and bacteria in the complex microenvironment,which can provide insights for the treatment of complex diseases with antibacterial requirements.
