Journal of the Mechanical Behavior of Biomedical Materials最新文献

{"title":"Biological tissue for transcatheter aortic valve: The effect of crimping on fatigue strength","authors":"Foued Khoffi ,&nbsp;Amanda C. Mills ,&nbsp;Martin W. King ,&nbsp;Frederic Heim","doi":"10.1016/j.jmbbm.2024.106741","DOIUrl":"10.1016/j.jmbbm.2024.106741","url":null,"abstract":"<div><p>Transcatheter aortic valve replacement (TAVR) has become today the most attractive procedure to relieve patients from aortic valve disease. However, the procedure requires crimping biological tissue within a metallic stent for low diameter catheter insertion purpose. This step induces specific stress in the leaflets especially when the crimping diameter is small. One concern about crimping is the potential degradations undergone by the biological tissue, which may limit the durability of the valve once implanted. The purpose of the present work is to investigate the mechanical damage undergone by bovine pericardium tissue during compression and analyze how this degradation evolves with time under fatigue testing conditions. Pericardium 500 μm thick pericardium ribbons (5 mm large, 70 mm long) were crimped down to 12 Fr for 30 and 50 min within a metallic stent to replicate the heart valve crimping configuration. After crimping, samples underwent cyclic fatigue flexure and pressure loading over 0.5 Mio cycles. Samples were characterized for mechanical performances before crimping, after crimping and after fatigue testing in order to assess potential changes in the mechanical properties of the tissue after each step. Results bring out that the ultimate tensile strength is not modified through the process. However an increase in the modulus shows that the crimping step tends to stiffen the pericardium. This may have an influence on the lifetime of the implant.</p></div>","PeriodicalId":380,"journal":{"name":"Journal of the Mechanical Behavior of Biomedical Materials","volume":"160 ","pages":"Article 106741"},"PeriodicalIF":3.3,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142228575","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":"Numerical simulation and analysis of fatigue performance for the humeral stem","authors":"Haitao Xie ,&nbsp;Haiqiong Xie ,&nbsp;Wei Chen ,&nbsp;Jinghua Zeng ,&nbsp;Xu Tao ,&nbsp;Hao Li","doi":"10.1016/j.jmbbm.2024.106738","DOIUrl":"10.1016/j.jmbbm.2024.106738","url":null,"abstract":"<div><h3>Background and objective</h3><p>Fatigue failure of the humeral stem is a severe long-term failure after shoulder arthroplasty, causing harm to patients and resulting in complex revision surgeries. However, there are few studies on humeral stem fatigue testing, and corresponding testing standards have not been established. Therefore, this study aims to investigate the fatigue performance of the humeral stem by establishing an efficient numerical simulation method.</p></div><div><h3>Methods</h3><p>Material properties are obtained by uniaxial tensile and fatigue tests. A parameterized static analysis program was written, and an automated fatigue numerical simulation platform was established using Abaqus, Fe-safe, and Isight in combination, enabling the establishment of a numerical simulation method for the fatigue performance of the humeral stem.</p></div><div><h3>Result</h3><p>Standard testing conditions include an 8 mm diameter humeral stem, a 40-21B humeral head, an 8° tilt angle, and a 2 mm fillet radius. Further research found that the fatigue life of the humeral stem decreases with increasing patient weight, and patients should control their weight after surgery.</p></div><div><h3>Conclusions</h3><p>The established automated fatigue numerical simulation platform avoids repetitive operations and efficiently completes large-scale calculations, guiding preoperative humeral stem selection and testing.</p></div>","PeriodicalId":380,"journal":{"name":"Journal of the Mechanical Behavior of Biomedical Materials","volume":"160 ","pages":"Article 106738"},"PeriodicalIF":3.3,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142233799","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":"Mechanical investigation of a Tandem embolization-visualization system for minimally invasive procedures","authors":"Peng Chen,&nbsp;George Varghese P J,&nbsp;Keren Zhao,&nbsp;Jingjie Hu","doi":"10.1016/j.jmbbm.2024.106739","DOIUrl":"10.1016/j.jmbbm.2024.106739","url":null,"abstract":"<div><p>Transcatheter arterial embolization is a minimally invasive intervention process in which the blood supply to a tumor or an abnormal area of tissue is blocked. One of the most commonly used embolic agents in clinics is microsphere (MS). In order to understand the flow behavior of microspheres in arteries, it is essential to study their mechanical properties systematically. In this work, calcium-alginate MSs with varying calcium concentrations were synthesized using a coaxial airflow method. Indocyanine green (ICG) was added as a fluorescent dye. The effect of ICG concentration change on microspheres was investigated by studying morphology, imageability, rheology, and swelling behavior. Then the effect of calcium chloride concentration change on microspheres was studied by conducting rheological tests, atomic force microscopy tests, hemolysis assay, and thrombogenicity assay. Results showed that microspheres with higher ICG concentrations have longer lasting fluorescence and lower storage modulus (G′). Higher concentrations of calcium chloride led to higher G′, while the local Young's modulus obtained by AFM test was not significantly affected. The MSs with and without ICG showed good hemocompatibility and thrombogenicity.</p></div>","PeriodicalId":380,"journal":{"name":"Journal of the Mechanical Behavior of Biomedical Materials","volume":"160 ","pages":"Article 106739"},"PeriodicalIF":3.3,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142228576","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":"Understanding the effects of mineralization and structure on the mechanical properties of tendon-bone insertion using mesoscale computational modeling","authors":"Zhangke Yang ,&nbsp;Daniel Gordon ,&nbsp;Yitong Chen ,&nbsp;Hui Li ,&nbsp;Yongren Wu ,&nbsp;Zhaoxu Meng","doi":"10.1016/j.jmbbm.2024.106735","DOIUrl":"10.1016/j.jmbbm.2024.106735","url":null,"abstract":"<div><p>Tendon-bone fibrocartilaginous insertion, or enthesis, is a specialized interfacial region that connects tendon and bone, effectively transferring forces while minimizing stress concentrations. Previous studies have shown that insertion features gradient mineralization and branching fiber structure, which are believed to play critical roles in its excellent function. However, the specific structure-function relationship, particularly the effects of mineralization and structure at the mesoscale fiber level on the properties and function of insertion, remains poorly understood. In this study, we develop mesoscale computational models of the distinct fiber organization at tendon-bone insertions, capturing the branching network from tendon to interface fibers and the different mineralization scales. We specifically analyze three key descriptors: the mineralization scale of interface fibers, the mean, and relative standard deviation of the local branching angles of interface fibers. Tensile test simulations on insertion models with varying mineralization scales of interface fibers and structures are performed to mimic the primary loading condition applied to the insertion. We measure and analyze five representative mechanical properties: Young's modulus, strength, toughness, resilience, and failure strain. Our results reveal that mechanical properties are significantly influenced by the three key descriptors, with tradeoffs observed between mutually exclusive properties. For instance, strength and resilience plateau beyond a certain mineralization scale, while failure strain and Young's modulus exhibit monotonic decreasing and increasing trends, respectively. Consequently, there exists an optimal mineralization scale for toughness due to these tradeoffs. By analyzing the mesoscale deformation and failure mechanisms from simulation trajectories, we identify three fracture regimes closely related to the trends in mechanical properties, supporting the observed tradeoffs. Additionally, we examine in detail the effects of the mean and relative standard deviation of local branching angles on mechanical properties and deformation mechanisms. Overall, our study enhances the fundamental understanding of the composition-structure-function relationships at the tendon-bone insertion, complementing recent experimental studies. The mechanical insights from our work have the potential to guide the future biomimetic design of fibrillar adhesives and interfaces for joining soft and hard materials.</p></div>","PeriodicalId":380,"journal":{"name":"Journal of the Mechanical Behavior of Biomedical Materials","volume":"160 ","pages":"Article 106735"},"PeriodicalIF":3.3,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142240887","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":"Synthesis and evaluation of novel urethane macromonomers for the formulation of fracture tough 3D printable dental materials","authors":"Florian Schönl ,&nbsp;Martin Demleitner ,&nbsp;Jörg Angermann ,&nbsp;Pascal Fässler ,&nbsp;Iris Lamparth ,&nbsp;Kai Rist ,&nbsp;Thomas Schnur ,&nbsp;Yohann Catel ,&nbsp;Sabine Rosenfeldt ,&nbsp;Holger Ruckdäschel","doi":"10.1016/j.jmbbm.2024.106737","DOIUrl":"10.1016/j.jmbbm.2024.106737","url":null,"abstract":"<div><p>3D printing of materials which combine fracture toughness, high modulus and high strength is quite challenging. Most commercially available 3D printing resins contain a mixture of multifunctional (meth)acrylates. The resulting 3D printed materials are therefore brittle and not adapted for the preparation of denture bases. For this reason, this article focuses on toughening by incorporation of triblock copolymers in methacrylate-based materials. In a first step, three urethane dimethacrylates with various alkyl spacer length were synthesized in a one-pot two-step synthesis. Each monomer was combined with 2-phenoxyethyl methacrylate as a monofunctional monomer and a polycaprolactone-polydimethylsiloxane-polycaprolactone triblock copolymer was added as toughener. The formation of nanostructures via self-assembly was proven by small angle X-ray scattering (SAXS) and transmission electron microscopy (TEM). The addition of the triblock copolymer resulted in a strong increase in fracture toughness for all mixtures. The nature of the urethane dimethacrylate had a significant impact on fracture toughness and flexural strength and modulus of the cured materials. Most promising systems were also investigated via dynamic fatigue propagation da/dN measurements, confirming that the toughening also works under dynamic load. By carefully selecting the length of the urethane dimethacrylate spacer and the amount of block copolymer, materials with the desired physical properties could be efficiently formulated. Especially the formulation containing the medium alkyl spacer length (<strong>DMA2</strong>/PEMA) and 5 wt% <strong>BCP1</strong> (block copolymer), exhibits excellent mechanical properties and high fracture toughness.</p></div>","PeriodicalId":380,"journal":{"name":"Journal of the Mechanical Behavior of Biomedical Materials","volume":"160 ","pages":"Article 106737"},"PeriodicalIF":3.3,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S1751616124003692/pdfft?md5=701dfd516c7667bd51e1731c7d519a5b&pid=1-s2.0-S1751616124003692-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142240889","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":"Fatigue strength of bilayer yttria-stabilized zirconia after low-temperature degradation","authors":"Raíssa Monteiro Pereira ,&nbsp;Renan Belli ,&nbsp;Ulrich Lohbauer ,&nbsp;Katrin Hurle ,&nbsp;Tiago Moreira Bastos Campos ,&nbsp;Gilmar Patrocínio Thim","doi":"10.1016/j.jmbbm.2024.106725","DOIUrl":"10.1016/j.jmbbm.2024.106725","url":null,"abstract":"<div><p>This study examined the impact of interfacial interactions on bilayer yttria-stabilized zirconia (YSZ) used in dental restorations. In-house bilayer structures of 3YSZ and 5YSZ composition underwent hydrothermal degradation to compare the properties of control and low-temperature degradation (LTD) treated groups. Biaxial flexural strength via piston-on-three-balls, staircase fatigue strength over 10⁶ cycles at 15 Hz, phase characterization and quantification through XRD and Rietveld refinement, and fractography were conducted. Weibull analysis was employed to determine the Weibull modulus and characteristic strength. Results demonstrated an enhancement in the mechanical performance of 3YSZ composition after LTD treatment, whereas the mechanical properties of 5YSZ remained largely unaffected post-degradation. Fractographic analysis revealed that failure originated at the surface tensile location across all specimen groups. These findings offer insights into the mechanical behavior of bilayer zirconia structures and reinforce the significance of hydrothermal treatment in enhancing their performance, particularly in the case of 3Y compositions.</p></div>","PeriodicalId":380,"journal":{"name":"Journal of the Mechanical Behavior of Biomedical Materials","volume":"160 ","pages":"Article 106725"},"PeriodicalIF":3.3,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142173289","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":"Biomechanical simulation of segmented intrusion of a mandibular canine using Robot Orthodontic Measurement & Simulation System (ROSS)","authors":"Hisham Sabbagh,&nbsp;Benedikt Dotzer,&nbsp;Uwe Baumert,&nbsp;Linus Hötzel,&nbsp;Corinna Lesley Seidel,&nbsp;Andrea Wichelhaus","doi":"10.1016/j.jmbbm.2024.106720","DOIUrl":"10.1016/j.jmbbm.2024.106720","url":null,"abstract":"<div><h3>Objective</h3><p>Aim of this study was to investigate the forces and moments during segmented intrusion of a mandibular canine using Cantilever-Intrusion-Springs (CIS).</p></div><div><h3>Methods</h3><p>Three different CIS modifications were investigated using a robotic biomechanical simulation system: unmodified CIS (#1, control), CIS with a lingual directed 6° toe-in bend (#2), and CIS with an additional 20° twist bend (#3). Tooth movement was simulated by the apparative robotic stand, controlled by a force-control algorithm, recording the acting forces and moments with a force-torque sensor. Statistical analysis was performed using Shapiro-Wilk, Kolmogorov-Smirnov, Kruskal-Wallis ANOVA and post hoc tests with Bonferroni correction (α = 0.05).</p></div><div><h3>Results</h3><p>The initial intrusive force, which was uniformly generated by a 35° Tip-Back bend, decreased significantly (p &lt; 0.05) from 0.31 N in group (#1) to 0.28 N in group (#3). Vestibular crown tipping reduced significantly (p &lt; 0.05) from 2.11° in group (#1) and 1.72° in group (#2) to 0.05° in group (#3). Matching to that the direction of orovestibular force significantly (p &lt; 0.05) shifted from 0.15 N to vestibular in group (#1) to 0.51 N to oral in group (#3) and the orovestibular tipping moment decreased also significantly (p &lt; 0.05) from 4.63 Nmm to vestibular in group (#1) to 3.56 Nmm in group (#2) and reversed to 1.20 Nmm to oral in group (#3). Apart from that the orovestibular displacement changed significantly (p &lt; 0.05) from 0.66 mm in buccal direction in group (#1) to 0.29 mm orally in group (#2) and 1.49 mm in oral direction as well in group (#3).</p></div><div><h3>Significance</h3><p>None of the modifications studied achieved pure mandibular canine intrusion without collateral effects. The significant lingual displacement caused by modification (#3) is, not least from an aesthetic perspective, considered much more severe than a slight tipping of the canine. Consequently, modification (#2) can be recommended for clinical application based on the biomechanical findings.</p></div>","PeriodicalId":380,"journal":{"name":"Journal of the Mechanical Behavior of Biomedical Materials","volume":"160 ","pages":"Article 106720"},"PeriodicalIF":3.3,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S1751616124003527/pdfft?md5=8d0bc472c53040c750365948fa501677&pid=1-s2.0-S1751616124003527-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142150377","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":"Characterization of damage mechanisms in cortical bone: Quantification of fracture resistance, critical strains, and crack tortuosity","authors":"Anna Gustafsson ,&nbsp;Giulia Galteri ,&nbsp;Arthur Barakat ,&nbsp;Jonas Engqvist ,&nbsp;Lorenzo Grassi ,&nbsp;Luca Cristofolini ,&nbsp;Hector Dejea ,&nbsp;Hanna Isaksson","doi":"10.1016/j.jmbbm.2024.106721","DOIUrl":"10.1016/j.jmbbm.2024.106721","url":null,"abstract":"<div><p>One step towards understanding bone fragility and degenerative diseases is to unravel the links between fracture resistance and the compositional and structural characteristics of cortical bone. In this study, we explore an optical method for automatic crack detection to generate full fracture resistance curves of cortical bone. We quantify fracture toughness, critical failure strains at the crack tip, and crack tortuosity in three directions and analyze how they relate to cortical bone microstructure.</p><p>A three-point bending fracture test of single-edge notched beam specimens in three directions (cracks propagating transverse, radial and longitudinal to the microstructure) from bovine cortical bone was combined with 2D-digital image correlation. Crack growth was automatically monitored by analyzing discontinuities in the displacement field using phase congruency analysis. Fracture resistance was analyzed using J-R-curves and strains were quantified at the crack tip. Post-testing, a subset of specimens was scanned using micro-tomography to visualize cracks and to quantify their tortuosity.</p><p>Both fracture toughness and crack tortuosity were significantly higher in the transverse direction compared to the other directions. Similar fracture toughness was found for radial and longitudinal directions, albeit 20% higher crack tortuosity in the radial specimens. This suggests that radial crack deflections are not as efficient toughening mechanisms. Strains at crack initiation were ∼0.4% for all tissue orientations, while at fully developed damage process zones failure strains were significantly higher in the transverse direction (∼1.5%). Altogether, we present unique quantitative data including different aspects of bone damage in three directions, illustrating the importance of cortical bone microstructure.</p></div>","PeriodicalId":380,"journal":{"name":"Journal of the Mechanical Behavior of Biomedical Materials","volume":"160 ","pages":"Article 106721"},"PeriodicalIF":3.3,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S1751616124003539/pdfft?md5=ac71da9fba2f69664daf41b38f570386&pid=1-s2.0-S1751616124003539-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142240884","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":"Influence of different cutting instruments and rotational speeds on heat generation and cutting efficiency when sectioning different types of zirconia","authors":"Lisa Türp,&nbsp;Frank Lehmann,&nbsp;Sebastian Wille,&nbsp;Matthias Kern","doi":"10.1016/j.jmbbm.2024.106715","DOIUrl":"10.1016/j.jmbbm.2024.106715","url":null,"abstract":"<div><h3>Purpose</h3><p>The purpose of this study was to evaluate the temperature generated on the intaglio surface and efficiency when cutting different types of zirconia with different rotary instruments and rotational speeds.</p></div><div><h3>Methods</h3><p>A conventional diamond rotary instrument (Brasseler, grit size 107 μm) and special diamond rotary instrument marketed to cut zirconia (4 ZR, Brasseler, grit size 126 μm) were tested on 3Y-TZP and 4Y-TZP zirconia with a rotation speed of 100,000 rpm and 200,000 rpm. Zirconia specimens were cut under water cooling (110 mL/min) in a custom-made holder attached to a universal testing machine. The temperature was recorded with infrared sensors pointing at the intaglio surface of the zirconia specimens.</p></div><div><h3>Results</h3><p>A rotation speed of 200,000 rpm resulted in significantly shorter cutting times, but also in significantly higher temperatures at the intaglio surface of the zirconia specimens compared with a rotation speed of 100,000 rpm. Significantly shorter cutting times were observed for the conventional diamond rotary instrument than for the special rotary instrument marketed to cut zirconia. Using the special rotary instrument, significantly longer cutting times were recorded for 3Y-TZP than for 4Y-TZP.</p></div><div><h3>Conclusions</h3><p>A conventional diamond rotary instrument was more efficient than a special rotary instrument. However, to avoid high temperatures when cutting zirconia clinically, a rotation speed of 100,000 rpm is recommended.</p></div>","PeriodicalId":380,"journal":{"name":"Journal of the Mechanical Behavior of Biomedical Materials","volume":"160 ","pages":"Article 106715"},"PeriodicalIF":3.3,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S1751616124003473/pdfft?md5=78e1619198ee9525b027fbaf138a077f&pid=1-s2.0-S1751616124003473-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142167818","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":"Influence of connection design and material properties on stress distribution and fatigue lifetime of zygomatic implants: A finite element analysis","authors":"Laura H.J. Alberto ,&nbsp;Saadman Alamgir ,&nbsp;Jason A. Griggs ,&nbsp;Michael D. Roach ,&nbsp;Randal S. Williamson ,&nbsp;Ravi Chandran ,&nbsp;Matthew W. Priddy ,&nbsp;Yuefeng J. Lu ,&nbsp;Patrick F. Bergin ,&nbsp;Yuanyuan Duan","doi":"10.1016/j.jmbbm.2024.106723","DOIUrl":"10.1016/j.jmbbm.2024.106723","url":null,"abstract":"<div><p>Zygomatic implants (ZIs) were developed as a graftless alternative to rehabilitate severely reabsorbed maxillae. This study aims to employ three-dimensional finite element analysis (FEA) to simulate the impact of external hexagonal implant connection (EHC) and internal hexagonal implant connection (IHC) on the stress distribution and fatigue lifetime within the ZI systems using parameters defined in ISO 14801:2016. Two ZI assemblies (Nobel Biocare and Noris Medical) were scanned in a micro-CT scanner and reconstructed using Nrecon software. Three-dimensional models were generated by Simpleware ScanIP Medical software. All models were exported to FEA software (ABAQUS) and subsequently to a fatigue analysis software (Fe-safe). A compressive 150 N load was applied at a 40° angle on the cap surface. A 15 Hz frequency was applied in the in silico cyclic test. The implant components had material properties of commercially pure grade 4 titanium (CPTi) and Titanium-6Aluminum-4Vanadium alloy (Ti64). Von Mises stress data, contour plots, and fatigue limits were collected and analyzed. EHC models exhibited higher peak stresses in implant components for both materials compared to IHC models. However, simulated bone support results showed the opposite trend, with higher stresses on IHCthan EHC models. The fatigue analysis revealed that assemblies with both designs exceeded ISO 14801:2016 number of cycles limits using Ti64, while CPTi groups exhibited comparatively lower worst life-repeats. In conclusion, ZIs with IHC were found to have a more homogeneous and advantageous stress distribution within both materials tested. Ti64 demonstrates a prolonged service life for both design connections.</p></div>","PeriodicalId":380,"journal":{"name":"Journal of the Mechanical Behavior of Biomedical Materials","volume":"160 ","pages":"Article 106723"},"PeriodicalIF":3.3,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142163821","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}