With continuous developments in additive manufacturing technology, tantalum (Ta) metal has been manufactured into orthopaedic implants with a variety of forms, properties and uses by three-dimensional printing. Based ...With continuous developments in additive manufacturing technology, tantalum (Ta) metal has been manufactured into orthopaedic implants with a variety of forms, properties and uses by three-dimensional printing. Based on extensive research in recent years, the design, processing and performance aspects of this new orthopaedic implant material have been greatly improved. Besides the bionic porous structure and mechanical characteristics that are similar to human bone tissue, porous tantalum is considered to be a viable bone repair material due to its outstanding corrosion resistance, biocompatibility, bone integration and bone conductivity. Numerous in vitro, in vivo, and clinical studies have been carried out in order to analyse the safety and efficacy of these implants in orthopaedic applications. This study reviews the most recent advances in manufacturing, characteristics and clinical application of porous tantalum materials.展开更多
Bone plates play a vital role in bone fracture healing by providing the necessary mechanical fixation for fracture fragments through modulating biomechanical microenvironment adjacent to the fracture site.Good treatme...Bone plates play a vital role in bone fracture healing by providing the necessary mechanical fixation for fracture fragments through modulating biomechanical microenvironment adjacent to the fracture site.Good treatment effect has been achieved for fixation of bone fracture with conventional bone plates,which are made of stainless steel or titanium alloy.However,several limitations still exist with traditional bone plates including loosening and stress shielding due to significant difference in modulus between metal material and bone tissue that impairs optimal fracture healing.Additionally,due to demographic changes and non-physiological loading,the population suffering from refractory fractures,such as osteoporosis fractures and comminuted fractures,is increasing,which imposes a big challenge to traditional bone plates developed for normal bone fracture repair.Therefore,optimal fracture treatment with adequate fixation implants in terms of materials and design relevant to special conditions is desirable.In this review,the complex physiological process of bone healing is introduced,followed by reviewing the development of implant design and biomaterials for bone plates.Finally,we discuss recent development of hybrid bone plates that contains bioactive elements or factors for fracture healing enhancement as a promising direction.This includes biodegradable Mg-based alloy used for designing bone screw-plates that has been proven to be beneficial for fracture healing,an innovative development that attracts more and more attention.This paper also indicates that the tantalum bone plates with porous structure are also emerging as a new fracture internal fixation implants.The reduction of the stress shielding is verified to be useful to accelerate bone fracture healing.Potential application of biodegradable metals may also avoid a second operation for implant removal.Further developments in biometals and their design for orthopedic bone plates are expected to improve the treatment of bone fracture,especially the refractory fractures.展开更多
Metal plates have always been the gold standard in the clinic for internal fracture fixation due to their high strength advantages.However,high elastic modulus can cause stress shielding and lead to bone embrittlement...Metal plates have always been the gold standard in the clinic for internal fracture fixation due to their high strength advantages.However,high elastic modulus can cause stress shielding and lead to bone embrittlement.This study used an electron beam melting method to prepare personalized porous Ti6Al4V(pTi)bone plates.Then,chemical vapor deposition(CVD)technology coats tantalum(Ta)metal on the pTi bone plates.The prepared porous Ta-coated bone plate has an elastic modulus similar to cortical bone,and no stress shielding occurred.In vitro experiments showed that compared with pTi plates,Ta coating significantly enhances the attachment and proliferation of cells on the surface of the scaffold.To better evaluate the function of the Ta-coated bone plate,animal experiments were conducted using a coat tibia fracture model.Our results showed that the Ta-coated bone plate could effectively fix the fracture.Both imaging and histological analysis showed that the Ta-coated bone plate had prominent indirect binding of callus formation.Histological results showed that new bone grew at the interface and formed good osseointegration with the host bone.Therefore,this study provides an alternative to bio-functional Ta-coated bone plates with improved osseointegration and osteogenic functions for orthopaedic applications.展开更多
Spinal fracture is a serious problem impairing life quality,associating with low back pain and many other chronic diseases.Among all the spinal fractures,the rate of thoracolumbar fractures is the highest and accounts...Spinal fracture is a serious problem impairing life quality,associating with low back pain and many other chronic diseases.Among all the spinal fractures,the rate of thoracolumbar fractures is the highest and accounts for approximately 90%.Although surgical treatment is an effective approach,it is still unclear which treatment method performs the best.The aim of the present study was to investigate the biomechanical performance of three spinal implants for treating the thoracolumbar wedge-shaped burst fractures using the finite element(FE)method.FE model of the T12/L1/L2 spinal segment was created from CT images and the thoracolumbar wedge-shaped burst fractures were created by removing some elements in the anterior part of L1.The FE models of the traditional system,the universal spine system(USS)and the cortical bone trajectory(CBT)system were created and their biomechanical performances were evaluated.The results revealed that among the three fixation systems,the highest von-Mises stress occurred in the CBT system.Under all the loading scenarios except for the lateral bending,the maximal von-Mises stress was higher when the USS system rather than the traditional system was applied.The average displacement around the fracture site was the highest in the CBT system.Except for the lateral bending,the average displacement around the fracture site was higher when the USS system rather than the traditional system was applied.For all the fixation approaches,the highest von-Mises stress always occurred at the screw junctions.The present study provided important data for the treatment of thoracolumbar wedge-shaped burst fractures.For example,the traditional spinal system is preferentially selected for the thoracolumbar wedgeshaped burst fracture of L1.展开更多
基金supported by the National Key Research&Development Program of China(2018YFA0606200)Sanming Project of Medicine in Shenzhen of China(SZSM202111001)Wellcome Trust(209734/Z/17/Z)。
基金the General Program of the National Natural Science Foundation of China,No.82172398。
文摘With continuous developments in additive manufacturing technology, tantalum (Ta) metal has been manufactured into orthopaedic implants with a variety of forms, properties and uses by three-dimensional printing. Based on extensive research in recent years, the design, processing and performance aspects of this new orthopaedic implant material have been greatly improved. Besides the bionic porous structure and mechanical characteristics that are similar to human bone tissue, porous tantalum is considered to be a viable bone repair material due to its outstanding corrosion resistance, biocompatibility, bone integration and bone conductivity. Numerous in vitro, in vivo, and clinical studies have been carried out in order to analyse the safety and efficacy of these implants in orthopaedic applications. This study reviews the most recent advances in manufacturing, characteristics and clinical application of porous tantalum materials.
基金supported by the National Key R&D Program of China(Grant No.2016YFC1102000)the National Natural Science Foundation of China(Grant Nos.81672139 and 81702129)+3 种基金the China Postdoctoral Science Foundation(No.171479)Doctor Initial Foundation of Liaoning Province(No.20170520017)Affiliated Zhongshan Hospital of Dalian University(No.DLDXZSYYDK201701)by a grant from the Research Grants Council of the Hong Kong Special Administrative Region,China(Project No.T13-402/17-N)。
文摘Bone plates play a vital role in bone fracture healing by providing the necessary mechanical fixation for fracture fragments through modulating biomechanical microenvironment adjacent to the fracture site.Good treatment effect has been achieved for fixation of bone fracture with conventional bone plates,which are made of stainless steel or titanium alloy.However,several limitations still exist with traditional bone plates including loosening and stress shielding due to significant difference in modulus between metal material and bone tissue that impairs optimal fracture healing.Additionally,due to demographic changes and non-physiological loading,the population suffering from refractory fractures,such as osteoporosis fractures and comminuted fractures,is increasing,which imposes a big challenge to traditional bone plates developed for normal bone fracture repair.Therefore,optimal fracture treatment with adequate fixation implants in terms of materials and design relevant to special conditions is desirable.In this review,the complex physiological process of bone healing is introduced,followed by reviewing the development of implant design and biomaterials for bone plates.Finally,we discuss recent development of hybrid bone plates that contains bioactive elements or factors for fracture healing enhancement as a promising direction.This includes biodegradable Mg-based alloy used for designing bone screw-plates that has been proven to be beneficial for fracture healing,an innovative development that attracts more and more attention.This paper also indicates that the tantalum bone plates with porous structure are also emerging as a new fracture internal fixation implants.The reduction of the stress shielding is verified to be useful to accelerate bone fracture healing.Potential application of biodegradable metals may also avoid a second operation for implant removal.Further developments in biometals and their design for orthopedic bone plates are expected to improve the treatment of bone fracture,especially the refractory fractures.
基金supported by the Dalian Science and Technology Innovation Fund Project(No.2018J11CY030).
文摘Metal plates have always been the gold standard in the clinic for internal fracture fixation due to their high strength advantages.However,high elastic modulus can cause stress shielding and lead to bone embrittlement.This study used an electron beam melting method to prepare personalized porous Ti6Al4V(pTi)bone plates.Then,chemical vapor deposition(CVD)technology coats tantalum(Ta)metal on the pTi bone plates.The prepared porous Ta-coated bone plate has an elastic modulus similar to cortical bone,and no stress shielding occurred.In vitro experiments showed that compared with pTi plates,Ta coating significantly enhances the attachment and proliferation of cells on the surface of the scaffold.To better evaluate the function of the Ta-coated bone plate,animal experiments were conducted using a coat tibia fracture model.Our results showed that the Ta-coated bone plate could effectively fix the fracture.Both imaging and histological analysis showed that the Ta-coated bone plate had prominent indirect binding of callus formation.Histological results showed that new bone grew at the interface and formed good osseointegration with the host bone.Therefore,this study provides an alternative to bio-functional Ta-coated bone plates with improved osseointegration and osteogenic functions for orthopaedic applications.
基金This study was supported by the National Natural Science Foundation of China(12072066)the DUT-BSU grant(ICR2103)the Chinese Fundamental Research Funds for the Central Universities(DUT21LK21).
文摘Spinal fracture is a serious problem impairing life quality,associating with low back pain and many other chronic diseases.Among all the spinal fractures,the rate of thoracolumbar fractures is the highest and accounts for approximately 90%.Although surgical treatment is an effective approach,it is still unclear which treatment method performs the best.The aim of the present study was to investigate the biomechanical performance of three spinal implants for treating the thoracolumbar wedge-shaped burst fractures using the finite element(FE)method.FE model of the T12/L1/L2 spinal segment was created from CT images and the thoracolumbar wedge-shaped burst fractures were created by removing some elements in the anterior part of L1.The FE models of the traditional system,the universal spine system(USS)and the cortical bone trajectory(CBT)system were created and their biomechanical performances were evaluated.The results revealed that among the three fixation systems,the highest von-Mises stress occurred in the CBT system.Under all the loading scenarios except for the lateral bending,the maximal von-Mises stress was higher when the USS system rather than the traditional system was applied.The average displacement around the fracture site was the highest in the CBT system.Except for the lateral bending,the average displacement around the fracture site was higher when the USS system rather than the traditional system was applied.For all the fixation approaches,the highest von-Mises stress always occurred at the screw junctions.The present study provided important data for the treatment of thoracolumbar wedge-shaped burst fractures.For example,the traditional spinal system is preferentially selected for the thoracolumbar wedgeshaped burst fracture of L1.
