A novel reconstructive prosthesis was designed with topological optimization(TO)and a lattice structure to enhance biomechanical and biological properties in the proximal tibia.The biomechanical performance was valida...A novel reconstructive prosthesis was designed with topological optimization(TO)and a lattice structure to enhance biomechanical and biological properties in the proximal tibia.The biomechanical performance was validated through finite element analysis(FEA)and biomechanical tests.The tibia with inhomogeneous material properties was reconstructed according to computed tomography images,and different components were designed to simulate the operation.Minimum compliance TO subject to a volume fraction constraint combined with a graded lattice structure was utilized to redesign the prosthesis.FEA was performed to evaluate the mechanical performances of the tibia and implants after optimization,including stress,micromotion,and strain energy.The results were analyzed by paired-samples t tests,and p<0.05 was considered significant.Biomechanical testing was used to verify the tibial stresses.Compared to the original group(OG),the TO group(TOG)exhibited lower stress on the stem,and the maximum von Mises stresses were 87.2 and 53.1 MPa,respectively,a 39.1%reduction(p<0.05).Conversely,the stress and strain energy on the tibia increased in the TOG.The maximum von Mises stress values were 16.4 MPa in the OG and 22.9 MPa in the TOG with a 39.6%increase(p<0.05),and the maximum SED value was 0.026 MPa in the OG and 0.042 MPa in the TOG,corresponding to an increase of 61.5%(p<0.05).The maximum micromotions in the distal end of the stem were 135μm in the OG and 68μm in the TOG,almost a 50%reduction.The stress curves of the biomechanical test coincided well with the FEA results.The TO approach can effectively reduce the whole weight of the prosthesis and improve the biomechanical environment of the tibia.It could also pave the way for next-generation applications in orthopedics surgery.展开更多
Custom-made pelvic prostheses are normally employed to reconstruct the biomechanics of the pelvis for improving patient＇s life quality. However, due to the large demand of biomechanical performance around the pelvic ...Custom-made pelvic prostheses are normally employed to reconstruct the biomechanics of the pelvis for improving patient＇s life quality. However, due to the large demand of biomechanical performance around the pelvic system, the customized prosthesis needs to be studied for its strength and stability. A hemi-pelvic finite element model, including a custom-made prosthesis and the surrounded main ligaments, was created to study the strength and stability of the system. Based on the developed finite element model, the relationship between the pre-stress of the screws and the biomechanical performance of the reconstructed pelvis was investigated. Results indicate that the pre-stress should not exceed 1000 N during surgery in order to prevent fatigue fractures from happening to screws. Moreover, four screws were removed from the pelvic system without affecting the fixing stability of the system, which provide surgical guidance for surgeons in terms of safety and fixation.展开更多
Ocular trauma is a very common incidence that occurs in up to 67%of patients with maxillofacial trauma.It results in life-long agony of not being like others with two eyes,which can see and admire the nature’s beauty...Ocular trauma is a very common incidence that occurs in up to 67%of patients with maxillofacial trauma.It results in life-long agony of not being like others with two eyes,which can see and admire the nature’s beauty.This article reports on a case of a 23-year-old male patient with phthisis bulbi,resulting from ocular trauma.The patient was rehabilitated aesthetically by fabrication of custom-made ocular prosthesis for his traumatically injured right eye.The patient was pleased with the aesthetic outcome,comfort,and mobility offered by the custom ocular prosthesis.There were no complications with regard to health of underlying residual ocular tissues and there was no need of relining of the prosthesis at 6 month recall appointment.Rehabilitation of patients with ocular trauma requires a multidisciplinary approach involving ophthalmologist,psychologist,and skilled maxillofacial prosthodontist.Custom-made ocular prosthesis fitted over the phthisical globe seems to be a highly positive,logical,noninvasive,and beneficial approach to increase mobility to the prosthesis,improve the cosmetic appearance and psychological well-being of the patient.展开更多
基金National Natural Science Foundation of China[Grant Numbers 81802174,81900726&82072456]Department of Science and Technology of Jilin Province,P.R.C[Grant Numbers 20200404202YY,20200403086SF&20200201453JC]+8 种基金Jilin Province Development and Reform Commission,P.R.C[Grant Number 2018C010]Education Department of Jilin Province,P.R.C[GrantNumber JJKH20180106KJ]Administration of Traditional Chinese Medicine of Jilin Province P.R.C[Grant Number 2018115]10th Youth Project of the First Hospital of Jilin University[Grant Number JDYY102019025]Department of Finance in Jilin Province[Grant Number 2019SCZT046]Undergraduate Teaching Reform Research Project of Jilin University[Grant Number 4Z2000610852]Key training plan for outstanding young teachers of Jilin University[Grant Number 419080520253]Bethune plan of Jilin University[Grant Number 470110000692]The major participant is Qing Han.
文摘A novel reconstructive prosthesis was designed with topological optimization(TO)and a lattice structure to enhance biomechanical and biological properties in the proximal tibia.The biomechanical performance was validated through finite element analysis(FEA)and biomechanical tests.The tibia with inhomogeneous material properties was reconstructed according to computed tomography images,and different components were designed to simulate the operation.Minimum compliance TO subject to a volume fraction constraint combined with a graded lattice structure was utilized to redesign the prosthesis.FEA was performed to evaluate the mechanical performances of the tibia and implants after optimization,including stress,micromotion,and strain energy.The results were analyzed by paired-samples t tests,and p<0.05 was considered significant.Biomechanical testing was used to verify the tibial stresses.Compared to the original group(OG),the TO group(TOG)exhibited lower stress on the stem,and the maximum von Mises stresses were 87.2 and 53.1 MPa,respectively,a 39.1%reduction(p<0.05).Conversely,the stress and strain energy on the tibia increased in the TOG.The maximum von Mises stress values were 16.4 MPa in the OG and 22.9 MPa in the TOG with a 39.6%increase(p<0.05),and the maximum SED value was 0.026 MPa in the OG and 0.042 MPa in the TOG,corresponding to an increase of 61.5%(p<0.05).The maximum micromotions in the distal end of the stem were 135μm in the OG and 68μm in the TOG,almost a 50%reduction.The stress curves of the biomechanical test coincided well with the FEA results.The TO approach can effectively reduce the whole weight of the prosthesis and improve the biomechanical environment of the tibia.It could also pave the way for next-generation applications in orthopedics surgery.
基金This work was supported by the Program of the National Natural Science Foundation of China （Grant Nos. 51205303 and 51323007）, the Fundamental Research Funds for the Central Universities, the Research Fund for the Doctoral Program of Higher Education of China （RFDP）, and the Program of International Scientific ＆ Technological Cooperation and Exchange Planning of Shaanxi Province （Grant No. 2017KW-ZD-02）.
文摘Custom-made pelvic prostheses are normally employed to reconstruct the biomechanics of the pelvis for improving patient＇s life quality. However, due to the large demand of biomechanical performance around the pelvic system, the customized prosthesis needs to be studied for its strength and stability. A hemi-pelvic finite element model, including a custom-made prosthesis and the surrounded main ligaments, was created to study the strength and stability of the system. Based on the developed finite element model, the relationship between the pre-stress of the screws and the biomechanical performance of the reconstructed pelvis was investigated. Results indicate that the pre-stress should not exceed 1000 N during surgery in order to prevent fatigue fractures from happening to screws. Moreover, four screws were removed from the pelvic system without affecting the fixing stability of the system, which provide surgical guidance for surgeons in terms of safety and fixation.
文摘Ocular trauma is a very common incidence that occurs in up to 67%of patients with maxillofacial trauma.It results in life-long agony of not being like others with two eyes,which can see and admire the nature’s beauty.This article reports on a case of a 23-year-old male patient with phthisis bulbi,resulting from ocular trauma.The patient was rehabilitated aesthetically by fabrication of custom-made ocular prosthesis for his traumatically injured right eye.The patient was pleased with the aesthetic outcome,comfort,and mobility offered by the custom ocular prosthesis.There were no complications with regard to health of underlying residual ocular tissues and there was no need of relining of the prosthesis at 6 month recall appointment.Rehabilitation of patients with ocular trauma requires a multidisciplinary approach involving ophthalmologist,psychologist,and skilled maxillofacial prosthodontist.Custom-made ocular prosthesis fitted over the phthisical globe seems to be a highly positive,logical,noninvasive,and beneficial approach to increase mobility to the prosthesis,improve the cosmetic appearance and psychological well-being of the patient.
