Journal of the Mechanical Behavior of Biomedical Materials最新文献

{"title":"Analysis of cutting forces and microdamage during indentation cutting of bone","authors":"Ger Reilly ,&nbsp;David Taylor","doi":"10.1016/j.jmbbm.2024.106870","DOIUrl":"10.1016/j.jmbbm.2024.106870","url":null,"abstract":"<div><div>In surgery, bone can be cut by applying force to a wedge-shaped blade. The published literature is relatively sparse regarding the biomechanics of this type of indentation cutting, especially regarding the relationships between blade geometry, bone quality, cutting force and microdamage. Microdamage created near the cut surfaces can be beneficial, as a trigger for bone remodelling, but it is known that excessive fracture damage can prolong the healing time. In this research, specimens of compact bovine bone were tested by cutting using wedge blades of different geometries. We labelled and measured microdamage occurring during bone cutting for the first time. We found that there were statistically significant effects arising from the variation in wedge angle, edge radius and blade orientation (with respect to bone's anisotropic structure) on both the magnitude of the cutting force and the extent of the microdamage. Interestingly, we found that the amount of damage occurring during cutting is directly correlated to the cutting force which causes the damage, independent of other factors. This work contributes to a better understanding of the biomechanics of this important surgical cutting process.</div></div>","PeriodicalId":380,"journal":{"name":"Journal of the Mechanical Behavior of Biomedical Materials","volume":"163 ","pages":"Article 106870"},"PeriodicalIF":3.3,"publicationDate":"2024-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142901492","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Corrosion fatigue of as-extruded Mg-xGa alloys in simulated bodily fluids with various glucose contents","authors":"Jiebin Zou ,&nbsp;Jia Ma ,&nbsp;Ziyue Zhang ,&nbsp;Lingxiong Sun ,&nbsp;Mohammed R.I. Abueida ,&nbsp;Song Zhang ,&nbsp;Xiaopeng Lu ,&nbsp;Yan Li ,&nbsp;Hongyan Tang ,&nbsp;Qiang Wang","doi":"10.1016/j.jmbbm.2024.106866","DOIUrl":"10.1016/j.jmbbm.2024.106866","url":null,"abstract":"<div><div>The medical devices are subjected to dynamic loads and surrounding physiological condition of the bodily fluids, which will impact the degradation behavior of magnesium (Mg) alloy implants. In this work, the corrosion fatigue (CF) and corrosion behaviors of Mg-<em>x</em>Ga (<em>x</em> = 1, 1.5, and 2 wt%) alloys in Hank's balanced salt solutions (HBSS) with 1 g/L and 3 g/L glucose are thoroughly studied. It is concluded that Mg-2Ga alloy exhibits excellent mechanical and fatigue behaviors. Its ultimate tensile strength (UTS) is 234 MPa, yield strength (YS) is 145 MPa, elongation (EL) is 15%, fatigue limits (<em>σ</em>_<em>f</em>) is 111 MPa in air, 48 MPa in HBSS with 1 g/L glucose, and 66 MPa in HBSS with 3 g/L glucose. The high glucose content in simulated bodily fluids has the function of inhibiting the corrosion reaction of alloy which is favorable to CF.</div></div>","PeriodicalId":380,"journal":{"name":"Journal of the Mechanical Behavior of Biomedical Materials","volume":"163 ","pages":"Article 106866"},"PeriodicalIF":3.3,"publicationDate":"2024-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142857282","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Biodegradability, biocompatibility, and mechanical behavior of additively manufactured zinc scaffolds","authors":"Mahdi Kaveh ,&nbsp;Mohsen Badrossamay ,&nbsp;Ehsan Foroozmehr ,&nbsp;Mahshid Kharaziha","doi":"10.1016/j.jmbbm.2024.106868","DOIUrl":"10.1016/j.jmbbm.2024.106868","url":null,"abstract":"<div><div>Zinc is a promising material for biodegradable scaffolds due to its biocompatible nature and suitable degradation rate. However, its low mechanical strength limits its use in load-bearing applications. This study aims to address this challenge by optimizing the process parameters of pure zinc using laser-based powder bed fusion and designing zinc scaffolds with tailored structures. Scaffolds based on five different unit cell types (Diamond, gyroid, primitive, Fischer-Kock S, and I-WP) were designed and fabricated using the optimized process parameters. The resulting scaffolds were evaluated for mechanical properties, degradation behavior, and cytocompatibility evaluation. Results show that I-WP and primitive scaffolds exhibited superior mechanical properties with compressive yield strength of 36.1 ± 1.2 MPa and 33.5 ± 1.4 MPa, respectively. While all scaffolds displayed a degradation rate within the range of 0.14–0.15 mm/year, the I-WP and primitive design exhibited a slightly higher degradation rate (0.15 mm/year) compared to the gyroid, diamond, and Fischer Koch S scaffolds (0.14 mm/year). Zinc itself demonstrated excellent cytocompatibility, as evidenced by in vitro MTT assay and cell morphology studies. Unit cell morphology also could accelerate proliferation, where MG-63 cells formed bridges between the unit cell walls in Fischer Koch S scaffolds. Considering the targeted application (mandible or jawbone healing) and evaluating all findings, scaffolds with I-WP and primitive designs and wall thicknesses of 500 μm (S01) emerged as the most promising candidates in mandible healing injuries.</div></div>","PeriodicalId":380,"journal":{"name":"Journal of the Mechanical Behavior of Biomedical Materials","volume":"163 ","pages":"Article 106868"},"PeriodicalIF":3.3,"publicationDate":"2024-12-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142866778","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Margin quality, homogeneity, and internal porosity assessment of experimental short fiber-reinforced CAD/CAM composite","authors":"Enas Mangoush ,&nbsp;Sufyan Garoushi ,&nbsp;Jorma Määttä ,&nbsp;Pekka K. Vallittu ,&nbsp;Lippo Lassila ,&nbsp;Eija Säilynoja","doi":"10.1016/j.jmbbm.2024.106867","DOIUrl":"10.1016/j.jmbbm.2024.106867","url":null,"abstract":"<div><h3>Objectives</h3><div>The aim of this study was to evaluate the margin quality of anterior crowns made of experimental short fiber-reinforced CAD/CAM composite (SFRC CAD) block before and after cyclic fatigue aging. Moreover, to investigate the microstructure, homogeneity, and porosity of the SFRC CAD compared with other commercial CAD/CAM materials.</div></div><div><h3>Methods</h3><div>40 anterior crowns were milled from five CAD/CAM blocks divided into five groups (n = 8/group). The first group was made of lithium disilicate ceramic blocks (EM), the second of zirconia-reinforced lithium disilicate blocks (CD), the third of hybrid polymer-infiltrated ceramic network blocks (VE), the fourth of hybrid nanoparticle-filled resin blocks (CS), and the last of SFRC CAD blocks (SFRC). Crowns were inspected with stereomicroscope and margins irregularities were measured using FIJI software. Specimens were scanned using micro-CT to investigate porosity and homogeneity. Crowns were then subjected to cyclic fatigue aging (120,000 cycles, Fmax = 220 N) and margin irregularities were measured again. SEM/EDS and XPS analyses were employed.</div></div><div><h3>Results</h3><div>SFRC CAD group resulted in the least margin irregularity values compared to other groups before and after cyclic fatigue aging, and lithium disilicate group resulted in the highest margin irregularity values (p &lt; 0.05). Micro-CT scanning revealed a homogenous distribution of fillers of tested materials with low internal porosity.</div></div><div><h3>Significance</h3><div>Material type and fatigue aging significantly affect crown margin irregularities. Hybrid and resin-based groups resulted in less margins irregularities than ceramic-based ones. All tested materials have homogenous structures with low internal porosity within the range of imaging resolution.</div></div>","PeriodicalId":380,"journal":{"name":"Journal of the Mechanical Behavior of Biomedical Materials","volume":"163 ","pages":"Article 106867"},"PeriodicalIF":3.3,"publicationDate":"2024-12-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142857313","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhancing magnesium-based materials for biomedical applications using an innovative strategy of combined single point incremental forming and bioactive coating","authors":"Roberta Ruggiero ,&nbsp;Rosa Maria Marano ,&nbsp;Benedetta Marrelli ,&nbsp;Anastasia Facente ,&nbsp;Elisabetta Aiello ,&nbsp;Romina Conte ,&nbsp;Giuseppe Serratore ,&nbsp;Giuseppina Ambrogio ,&nbsp;Francesco Paduano ,&nbsp;Marco Tatullo","doi":"10.1016/j.jmbbm.2024.106858","DOIUrl":"10.1016/j.jmbbm.2024.106858","url":null,"abstract":"<div><h3>Background</h3><div>Magnesium (Mg) and its alloys are promising candidates for biodegradable materials in next-generation bone implants due to their favourable mechanical properties and biodegradability. However, their rapid degradation and corrosion, potentially leading to toxic byproducts, pose significant challenges for widespread use.</div></div><div><h3>Objectives</h3><div>This study aimed to address the challenges associated with Mg-based materials by thoroughly evaluating the biocompatibility, genotoxicity, and mechanical properties of Mg-based devices manufactured via Single Point Incremental Forming (SPIF). Additionally, the study explored the efficacy of a bioactive coating in enhancing the biocompatibility of these devices.</div></div><div><h3>Methods</h3><div>The biocompatibility of six different Mg-SPIF substrates was assessed using an indirect cytotoxicity assay while genotoxicity was evaluated using the Ames test. Mg-based implants were subjected to roughness and thickness tests, as well as metallographic observations. To enhance biocompatibility, a coating comprising sodium hydroxide (NaOH), ascorbic acid (AA), and bovine serum albumin (BSA) was applied to the most promising Mg-SPIF devices.</div></div><div><h3>Results</h3><div>None of the Mg-SPIF devices demonstrated genotoxicity. Out of the six devices evaluated, only two, which had lower surface roughness, exhibited the most favourable biocompatibility responses. Additionally, the surface functionalization strategy significantly enhanced the biocompatibility of these Mg-SPIF devices, demonstrating up to 70% improvement in cell viability compared to unmodified substrates, indicating substantial enhancement in biological performance.</div></div><div><h3>Conclusions</h3><div>These results underscore the potential of SPIF Mg-based materials, particularly when enhanced with a bioactive OH-AA-BSA coating, to revolutionize medical implant technology by providing a safer and more effective option for a wide range of biomedical applications. While these <em>in vitro</em> findings are very promising, translation to clinical applications requires comprehensive <em>in vivo</em> validation, focusing on degradation kinetics, local tissue response, and mechanical integrity under physiological conditions.</div></div>","PeriodicalId":380,"journal":{"name":"Journal of the Mechanical Behavior of Biomedical Materials","volume":"163 ","pages":"Article 106858"},"PeriodicalIF":3.3,"publicationDate":"2024-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142808972","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Developing porous hip implants implementing topology optimization based on the bone remodelling model and fatigue failure","authors":"Babak Ziaie ,&nbsp;Xavier Velay ,&nbsp;Waqas Saleem","doi":"10.1016/j.jmbbm.2024.106864","DOIUrl":"10.1016/j.jmbbm.2024.106864","url":null,"abstract":"<div><div>In contemporary orthopaedic practice, total hip arthroplasty (THA) is a reliable surgical technique for hip joint replacement. However, introducing solid implants into human bone tissue can lead to complications, notably stress shielding and cortical hypertrophy. These issues often stem from mechanical mismatches, particularly stiffness disparities, between the solid implants and the bone tissue. A potential solution lies in adopting porous implant structures with lower stiffness and tuneable mechanical properties based on morphological parameters such as porosity, relative density, and unit cell sizes. This study, which is of significant importance to orthopaedic implant development, aims to develop porous implants that meet biological and manufacturing requirements, employing topology optimization methods to address the challenges associated with conventional solid implants. To achieve this objective, we conducted finite element analyses to compare the stress distribution within healthy bones with solid and newly developed porous implants under real-life loading conditions. The porous implants were designed with triply periodic minimal surface structures, featuring uniform relative density and gradient relative density mapping derived from topology optimization results considering additive manufacturing capabilities and biological constraints. Our findings provide critical insights into the impact on the bone's mechanical environment about the choice of implant. Specifically, solid implants significantly decrease applied stress within the cortical bone, leading to stress shielding and subsequent bone resorption, consistent with bone remodelling principles and Wolff's law. However, replacing the solid implant with uniform porosity with maximum compliance and employing gradient porous implants based on topology optimization methods significantly increases the strain energy density ratio. Specifically, the uniform gyroid, uniform diamond, gradient gyroid, and gradient diamond stems exhibited increases of 43%, 39%, 27%, and 25%, respectively, compared to the solid stem, effectively mitigating the stress shielding effect. However, amongst porous stems, only gradient designs could meet the mechanical strength requirements with a safety factor greater than one, rendering them suitable replacements for solid implants aimed at addressing associated complications. These results hold promise, particularly with the advancements in additive manufacturing methods capable of fabricating these porous implants with acceptable precision.</div></div>","PeriodicalId":380,"journal":{"name":"Journal of the Mechanical Behavior of Biomedical Materials","volume":"163 ","pages":"Article 106864"},"PeriodicalIF":3.3,"publicationDate":"2024-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142866779","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Poroelastic and viscoelastic properties of soft materials determined from AFM force relaxation and force-distance curves","authors":"Stéphane Cuenot ,&nbsp;Arnaud Fillaudeau ,&nbsp;Tina Briolay ,&nbsp;Judith Fresquet ,&nbsp;Christophe Blanquart ,&nbsp;Eléna Ishow ,&nbsp;Agata Zykwinska","doi":"10.1016/j.jmbbm.2024.106865","DOIUrl":"10.1016/j.jmbbm.2024.106865","url":null,"abstract":"<div><div>In the field of tissue engineering, determining the mechanical properties of hydrogels is a key prerequisite to develop biomaterials mimicking the properties of the extracellular matrix. In mechanobiology, understanding the relationships between the mechanical properties and physiological state of cells is also essential. Time-dependent mechanical characterization of these soft materials is commonly achieved by atomic force microscopy (AFM) experiments in liquid environment. However, the determination of an appropriate model to correctly interpret the experimental data is often missing, making it difficult to extract quantitative mechanical properties. Here, force relaxation and force-distance curves were combined to elucidate the origin of dissipative processes involved in hydrogels and cells, before applying the relevant poroelastic or viscoelastic theory to model the curves. By using spherical AFM tips, analytical equations were developed to transform these curves into mechanical parameters by describing the relationships between the exerted force and the elastic, poroelastic or viscoelastic responses of semi-infinite and finite-thickness materials. Poroelastic behavior was evidenced for a thermoresponsive hydrogel and a set of poroelastic parameters was extracted from the force relaxation curves. In contrast, cells exhibited viscoelastic properties characterized by a single power-law relaxation over three-decade time scales. In addition, compressive modulus and fluidity exponent of cells were obtained by fitting force relaxation curves and approach-retraction force-distance curves. This combined theoretical and experimental framework opens a rigorous way toward quantitative mechanical properties of soft materials by (1) systematically determining the origin of their relaxation mechanisms, (2) defining the theoretical models to correctly interpret the experimental data, (3) using analytically solved equations to extract the mechanical parameters.</div></div>","PeriodicalId":380,"journal":{"name":"Journal of the Mechanical Behavior of Biomedical Materials","volume":"163 ","pages":"Article 106865"},"PeriodicalIF":3.3,"publicationDate":"2024-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142815433","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Super-fast and accurate nonlinear foot deformation Prediction using graph neural networks","authors":"Taehyeon Kang ,&nbsp;Jiho Kim ,&nbsp;Hyobi Lee ,&nbsp;Haeun Yum ,&nbsp;Chani Kwon ,&nbsp;Youngbin Lim ,&nbsp;Sangryun Lee ,&nbsp;Taeyong Lee","doi":"10.1016/j.jmbbm.2024.106859","DOIUrl":"10.1016/j.jmbbm.2024.106859","url":null,"abstract":"<div><div>Recently, there has been a significant increase in the number of foot diseases, highlighting the importance of non-surgical treatments. Customized insoles, tailored to an individual's foot morphology, have emerged as a promising solution. However, the traditional design process of the customized insole is both slow and expensive due to the high computational complexity of finite element analysis (FEA) required to predict deformations of the foot. This study explores the applicability of a graph neural network (GNN) based on the MeshGraphNet framework to predict the 3-D shape of the foot under load and test the performance of GNN depending on the number of datasets. A total of 186 3-D undeformed foot CAD geometries are obtained from a series of 2-D foot images with deformations predicted through FEA. This FEA data is then used to train the GNN model, which aims to predict foot displacement with high accuracy and computation speed. After optimization of the weights of the GNN, the model remarkably outperformed FEA simulations in speed, being approximately 97.52 times faster, while maintaining high accuracy, with <em>R</em>² values above 95% in predicting foot displacement. This breakthrough suggests that GNN models can greatly improve the efficiency and reduce the cost of manufacturing customized insoles, providing a significant advancement in non-surgical treatment options for foot conditions.</div></div>","PeriodicalId":380,"journal":{"name":"Journal of the Mechanical Behavior of Biomedical Materials","volume":"163 ","pages":"Article 106859"},"PeriodicalIF":3.3,"publicationDate":"2024-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142823027","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"In vivo assessment of shear modulus along the fibers of pennate muscle during passive lengthening and contraction using steered ultrasound push beams","authors":"Ricardo J. Andrade ,&nbsp;Ha-Hien-Phuong Ngo ,&nbsp;Alice Lemoine ,&nbsp;Apolline Racapé ,&nbsp;Nicolas Etaix ,&nbsp;Thomas Frappart ,&nbsp;Christophe Fraschini ,&nbsp;Jean-Luc Gennisson ,&nbsp;Antoine Nordez","doi":"10.1016/j.jmbbm.2024.106862","DOIUrl":"10.1016/j.jmbbm.2024.106862","url":null,"abstract":"<div><div>Ultrasound shear wave elastography (SWE) has emerged as a promising non-invasive method for muscle evaluation by assessing the propagation velocity of an induced shear wavefront. In skeletal muscles, the propagation of shear waves is complex, depending not only on the mechanical and acoustic properties of the tissue but also upon its geometry. This study aimed to comprehensively investigate the influence of muscle pennation angle on the shear wave propagation, which is directly related to the shear modulus. A novel elastography method based on steered pushing beams (SPB) was used to assess the shear modulus along the fibers of the <em>gastrocnemius medialis</em> (pennate) muscle in twenty healthy volunteers. Ultrasound scans were performed during passive muscle lengthening (n = 10) and submaximal isometric contractions (n = 10). The shear modulus along the fibers was compared to the apparent shear modulus, as commonly assessed along the muscle shortening direction using conventional SWE sequences. The shear modulus along the muscle fibers was significantly greater than the apparent shear modulus for passive dorsiflexion angles, while not significantly different throughout the range of plantar flexion angles (i.e., under any or very low tensile loads). The concomitant decrease in pennation angle along with the gradual increase in the shear modulus difference between the two methods as the muscle lengthens, strongly indicates that non-linear elasticity exerts a greater influence on wave propagation than muscle geometry. In addition, significant differences between methods were found across all submaximal contractions, with both shear modulus along the fibers and the pennation angle increasing with the contraction intensity. Specifically, incremental contraction intensity led to a greater bias than passive lengthening, which could be partly explained by distinct changes in pennation angle. Overall, the new SPB sequence provides a rapid and integrated geometrical correction of shear modulus quantification in pennate muscles, thereby eliminating the necessity for specialized systems to align the ultrasound transducer array with the fiber's orientation. We believe that this will contribute for improving the accuracy of SWE in biomechanical and clinical settings.</div></div>","PeriodicalId":380,"journal":{"name":"Journal of the Mechanical Behavior of Biomedical Materials","volume":"163 ","pages":"Article 106862"},"PeriodicalIF":3.3,"publicationDate":"2024-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142815432","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of structural design on the mechanical performances of poly-L-lactic acid cardiovascular scaffolds using FEA and in vitro methods","authors":"Jinwoo Kim ,&nbsp;Hyeon Ji Lee ,&nbsp;Eun Ae Choi ,&nbsp;Jung Ho Lee ,&nbsp;Jin Oh ,&nbsp;Dae-Heung Byeon ,&nbsp;Hyo Sung Kwak ,&nbsp;Chan Hee Park","doi":"10.1016/j.jmbbm.2024.106849","DOIUrl":"10.1016/j.jmbbm.2024.106849","url":null,"abstract":"<div><h3>Objective</h3><div>In this study, we propose distinct and novel types of scaffold geometries to improve the mechanical performance of Poly-L-lactic Acid (PLLA) bioresorbable vascular scaffolds (BVS), investigating how different geometries of PLLA BVS influence their mechanical performances through finite element analysis (FEA) and in vitro experiment methods.</div></div><div><h3>Methods</h3><div>Four different types of scaffold geometries were modelled for FEA and manufactured for in vitro experiments. PLLA tubes with 110 μm thickness were used in manufacturing the scaffolds. For FEA measurements, material properties and bilinear material models were obtained from tensile testing using the PLLA tubes employed for manufacturing. Various measurements were conducted including crush resistance, radial strength in both the laser-cut and deployed state, three-point bending, and scaffold crimping/expansion test.</div></div><div><h3>Results</h3><div>Overall, the FEA results were similar to the experimental results. Design A, which had a conventional open-cell geometry with straight bridges, showed inferior crush resistance and radial strength to those of the other tested geometries. Design B exhibited the most well-balanced scaffold performances in terms of radial strengths, crush resistance, three-point bending, and crimping/expansion behaviors. Notably, it showed minimum plastic strain during crimping and expanding deformations in FEA.</div></div><div><h3>Conclusions</h3><div>Findings from such distinct and novel types of scaffold geometries shown by this study may provide a valuable understanding using PLLA scaffolds as cardiovascular devices.</div></div>","PeriodicalId":380,"journal":{"name":"Journal of the Mechanical Behavior of Biomedical Materials","volume":"163 ","pages":"Article 106849"},"PeriodicalIF":3.3,"publicationDate":"2024-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142804291","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}