摘要：Total temporomandibular joint(TMJ)replacement is recommended only when there is irreversible damage to the joint and no conservative treatment can provide functional *** stock and custom-made TMJ implants have been made available;however,retrospective and comparative studies were unable to find significant differences between the two types of *** introduction of additive manufacturing(AM)techniques in medical practice allows for a greater freedom of design and a higher degree of device *** combination of AM with structural optimisation may streamline development and provide the key for fabricating biomechanic ally enhanced TMJ *** this study,structural optimis ation techniques were applied to develop and numerically validate a patient-specific TMJ *** biomechanical behaviour of each intermediate TMJ design was assessed under four different nominal and maximum biting tasks using finite element *** addition,a new set of metrics were proposed to compare each design regarding biomechanical performance and implant *** results suggest that 55-82%of the natural/intact strain patterns can be recovered with the finally selected TMJ *** represents an increase of 15%in biomechanical performance for incisor biting,15%for right molar biting,17%for left molar biting and a decrease of 2%for left group biting compared with the initial *** results also suggest that load transfer at the proximal ramus reduces the implant’s impact on the mandible’s strain ***,structural optimisation allows for a volume reduction of up to 44%with a minimum loss of implant safety and biomechanical performance.

摘要：Introduction Mandibular segmental defects result in significant cosmetic and functional ***,the reconstruction of both the contour and function of the mandible is a challenging *** present,autologous vascularized fibula transplantation is the most common method to reconstruct a mandible with long-span defects[1].

摘要：Three-dimensional(3D)-printed scaffolds have attracted considerable attention in recent years as they provide a suitable environment for bone cell tissue regeneration and can be customized in *** many other challenges,the material composition and geometric structure have major impacts on the performance of *** and tricalcium phosphate(HA/TCP),as the major constituents of natural bone and teeth,possess attractive biological properties and are widely used in bone scaffold *** fabrication methods have been investigated in attempts to achieve HA/TCP scaffolds with microporous structure enabling cell growth and nutrient ***,current 3D printing methods can only achieve the fabrication of HA/TCP scaffolds with certain range of microporous *** overcome this challenge,we developed a slurry-based microscale mask image projection stereolithography,allowing us to form a HA/TCP-based photocurable suspension with complex geometry including biomimetic features and hierarchical ***,the curing performance and physical properties of the HA/TCP suspension were investigated,and a circular movement process for the fabrication of highly viscous HA/TCP suspension was *** on these investigations,the scaffold composition was *** determined that a 30 wt%HA/TCP scaffold with biomimetic hierarchical structure exhibited superior mechanical properties and *** proliferation was investigated in vitro,and the surgery was conducted in a nude mouse in vivo model of long bone with cranial neural crest cells and bone marrow mesenchymal stem *** results showed our 3D-printed HA/TCP scaffold with biomimetic hierarchical structure is biocompatible and has sufficient mechanical strength for surgery.

摘要：In maxillofacial surgery, there is a significant need for the design and fabrication of porous scaffolds with customizable bionic structures and mechanical properties suitable for bone tissue engineering. In this paper, we characterize the porous Ti6Al4V implant, which is one of the most promising and attractive biomedical applications due to the similarity of its modulus to human bones. We describe the mechanical properties of this implant, which we suggest is capable of providing important biological functions for bone tissue regeneration. We characterize a novel bionic design and fabrication process for porous implants. A design concept of “reducing dimensions and designing layer by layer” was used to construct layered slice and rod-connected mesh structure (LSRCMS) implants. Porous LSRCMS implants with different parameters and porosities were fabricated by selective laser melting (SLM). Printed samples were evaluated by microstructure characterization, specific mechanical properties were analyzed by mechanical tests, and finite element analysis was used to digitally calculate the stress characteristics of the LSRCMS under loading forces. Our results show that the samples fabricated by SLM had good structure printing quality with reasonable pore sizes. The porosity, pore size, and strut thickness of manufactured samples ranged from (60.95± 0.27)% to (81.23±0.32)%,(480±28) to (685±31)μm, and (263±28) to (265±28)μm, respectively. The compression results show that the Young’s modulus and the yield strength ranged from (2.23±0.03) to (6.36±0.06) GPa and (21.36±0.42) to (122.85±3.85) MPa, respectively. We also show that the Young’s modulus and yield strength of the LSRCMS samples can be predicted by the Gibson-Ashby model. Further, we prove the structural stability of our novel design by finite element analysis. Our results illustrate that our novel SLM-fabricated porous Ti6Al4V scaffolds based on an LSRCMS are a promising material for bone implants, and are potential

摘要：Nanofibers can mimic natural tissue structure by creating a more suitable environment for cells to grow,prompting a wide application of nanofiber *** this review,we include relevant studies and characterize the effect of nanofibers on mesenchymal stem cells,as well as factors that affect cell adhesion and osteogenic *** hypothesize that the process of bone regeneration in vitro is similar to bone formation and healing in vivo,and the closer nanofibers or nanofibrous scaffolds are to natural bone tissue,the better the bone regeneration process will *** general,cells cultured on nanofibers have a similar gene expression pattern and osteogenic behavior as cells induced by osteogenic supplements in *** involved in cell adhesion(focal adhesion kinase(FAK)),cytoskeletal organization,and osteogenic pathways(transforming growth factor-β(TGF-β)/bone morphogenic protein(BMP),mitogen-activated protein kinase(MAPK),and Wnt)are upregulated *** adhesion and osteogenesis may be influenced by several *** possess certain physical properties including favorable hydrophilicity,porosity,and swelling properties that promote cell adhesion and ***,nanofiber stiffness plays a vital role in cell fate,as cell recruitment for osteogenesis tends to be better on stiffer scaffolds,with associated signaling pathways of integrin and Yes-associated protein(YAP)/transcriptional co-activator with PDZ-binding motif(TAZ).Also,hierarchically aligned nanofibers,as well as their combination with functional additives(growth factors,HA particles,etc.),contribute to osteogenesis and bone *** summary,previous studies have indicated that upon sensing the stiffness of the nanofibrous environment as well as its other characteristics,stem cells change their shape and tension accordingly,regulating downstream pathways followed by adhesion to nanofibers to contribute to ***,additional experiments are needed to id

摘要：Objective ：To investigate the feasibility of using natural poritos as scaffolds in bone tissue engineering （TE） and repair of caprine mandibular segmental defect with titanium reticulum reinforced. Methods： Natural poritos with a pore of 190-230 μm in size and porosity of about 50 %-65 % was molded into the shape of granules 5 mm × 5 mm × 5 mm in size. Expanded autologous caprine marrow mesenchymal stem cells were induced by recombinant human morphogenetic protein-2 （rhBMP2） to improve osteoblastic phenotype. Then marrow derived osteoblasts were seeded into poritos in density of 4 × 10^7/ml and incubated in vitro for 48 hours prior to implantation. Then osteoblastic cells/poritos complexes were implanted into mandibular defect and the defect was reinforced by titanium reticulum. Implantation of poritos alone acted as the control. Bone regeneration was assessed 4, 8, 16 weeks after implantation using roentgenographie analysis and histological observation was done after 16 weeks. Results： New bone could be observed histologically on the surface and in the pores of natural coral in all specimens in the cell-seeding group, whereas in the control group there was no evidence of osteogenesis process in the center of the construction. The results showed that new bone grafts were successfully restored 16 weeks after implantation. Conclusions： This study suggests the feasibility of using porous coral as scaffold material transplanted with marrow derived osteoblasts by TE method. By means of titanium reticulum reinforcement, mandibular defect could be successfully restored. It shows the potentiality of using this method for the reconstruction of bone defect in cfinic.

摘要：Osteoconductive function is remarkably low in bone disease in the absence of bone tissue surrounding the grafting site,or if the bone tissue is in poor ***,an effective bone graft in terms of both osteoconductivity and osteoinductivity is required for clinical ***,the three-dimensional(3D)kagome structure has been shown to be advantageous for bone tissue regeneration due to its mechanical *** this study,a polycaprolactone(PCL)kagome-structure scaffold containing a hyaluronic acid(HA)-based hydrogel was fabricated using a 3D printing *** retention capacity of the hydrogel in the scaffold was assessed in vivo with a rat calvaria subcutaneous model for 3 weeks,and the results were compared with those obtained with conventional 3D-printed PCL grid-structure scaffolds containing HA-based hydrogel and bulk-type HA-based *** retained hydrogel in the kagome-structure scaffold was further evaluated by in vivo imaging system *** further reinforce the osteoinductivity of the kagome-structure scaffold,a PCL kagome-structure scaffold with bone morphogenetic protein-2(BMP-2)containing HA hydrogel was fabricated and implanted in a calvarial defect model of rabbits for 16 *** bone regeneration characteristics were evaluated with hematoxylin and eosin(H&E),Masson’s trichrome staining,and micro-CT image analysis.

摘要：To the Editor:With great interest,we read the article by Zhou et al[1]entitled“Application of bilateral supraclavicular artery island flaps in the repair of hypopharyngeal and cervical skin defects:a case report.”The authors explored the potential of bilateral supraclavicular artery island(SAI)flaps for reconstructing through-andthrough defects between the hypopharyngeal mucosa and the neck skin resulting from salvage surgery for recurrent laryngeal *** we congratulate the authors on their successful surgical results,we think they should present more details about the surgical method,especially regarding the pre-operative imaging of the SAI flap,which was of crucial importance to the success of the *** would like to take the opportunity to offer some comments and further expand on the topic by presenting our current work involving the SAI flap.

摘要：Craniosynostosis is a rare disease in which one or more of the cranial sutures in an infant skull prematurely fuses by turning into bone,with a prevalence of 1 in 2,000—2,500 individuals from reports in Western countries(Wilkie et al.,2017).It may restrict the growth of the brain,leading to some degree of morphological and functional abnormalities,and may affect the neurocognitive function of infants(Lattanzi et al.,2017).Genetic variants underlying craniosynostosis have been identified in cohort studies in Western populations.

摘要：The vicious cycle between tumor cell proliferation and bone resorption remarkably elevates the progression and metastasis of bone ***,we fabricated polyethylene glycol-conjugated alendronate-functionalized and chloroquine(CQ)-loaded polydopamine nanoparticles(PPA/CQ)for efficient treatment of bone tumors via breaking the vicious *** nanoparticles were efficiently accumulated to the bone tissues,especially the osteolytic lesions around *** released from PPA/CQ inhibited osteoclastogenesis via preventing the degradation of tumor necrosis factor(TNF)receptor-associated receptor 3 to attenuate the osteolysis in bone *** the other hand,CQ blocked the autophagy in cancer cells,resulting in improved photothermal killing of cancer ***,the in vivo experiment revealed that PPA/CQ-associated treatment efficiently inhibited both tumor growth and *** work suggests that autophagy inhibition-associated photothermal therapy could be a promising strategy for treating malignant bone tumors.