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Vibroacoustic detection of inclusions in an elastomeric tissue phantom using a multilayer perceptron classifier: A proof-of-concept study 使用多层感知器分类器对弹性组织模体中内含物的振动声检测:概念验证研究
IF 3.5 2区 医学 Q2 ENGINEERING, BIOMEDICAL Pub Date : 2026-02-01 Epub Date: 2025-11-19 DOI: 10.1016/j.jmbbm.2025.107279
Mostafa Sayahkarajy , Florian Römer , Hartmut Witte
Accurate detection of tumor boundaries is critical for the success of oncologic surgical intervention. Traditionally, palpation can handover important information for tumor localization based on the tissue mechanical properties, but in Minimally Invasive Surgery no direct access to the tumor for palpation is feasible. For providing a technical analogy, this feasibility-level study focusses on the simplified problem of detection of an inclusion within a homogeneous silicon phantom. We hypothesized that existence of a relatively stiffer inclusion within an elastomer tissue phantom changes vibroacoustic signatures under forced vibration conditions. In comparison with previous studies, in this work the measurement probe was static, and the short-time (1 s) data package analysis targeted at nearly real-time inclusion detection. The inclusion detection problem was cast into a binary classification of the short-time acquired vibroacoustic signals. The method involves a wavelet-based multilayer perceptron neural network (MLP) that is trained in a supervised manner. A micro-electro-mechanical system (MEMS) sensor proximally attached to a solid probe was used to measure the vibroacoustic signals. Phantoms of simulated healthy tissue with stiffer tumor model inclusions were used for experiments and data collection. From the 120 overall number of experiments, 15 % were used as test data to evaluate the performance. The results show inclusion detection F1 score of 75 %, and 77.8 % accuracy related to the confusion matrix, reflecting the model performance on previously unseen data. Performance of the classifier was discussed in terms of various binary classification metrics, and compared with another established classifier, support vector machine (SVM). While the results support the hypothesis of this proof-of-concept study, extensions like improving the electronic system and refining the method with more experiments on biological tissues remain as the future work.
肿瘤边界的准确检测是肿瘤外科干预成功的关键。传统上,触诊可以根据组织力学特性传递肿瘤定位的重要信息,但在微创外科中,无法直接进入肿瘤进行触诊。为了提供一个技术上的类比,这个可行性级别的研究侧重于在均匀硅模体中检测包含物的简化问题。我们假设在弹性体组织模体中存在相对较硬的内含物会在强制振动条件下改变振动声学特征。与以往的研究相比,本研究的测量探针是静态的,短时间(1 s)数据包分析的目标是近实时的内含物检测。将夹杂物检测问题转化为对短时间采集的振动声信号进行二值分类。该方法涉及一个基于小波的多层感知器神经网络(MLP),该网络以监督方式训练。采用近端附着在固体探针上的微机电系统(MEMS)传感器来测量振动声信号。采用模拟健康组织的模型和较硬的肿瘤模型包涵体进行实验和数据收集。从120个实验总数中,15%作为测试数据来评估性能。结果表明,包含检测F1得分为75%,与混淆矩阵相关的准确率为77.8%,反映了模型对以前未见过的数据的性能。根据各种二值分类指标讨论了分类器的性能,并与另一种已建立的分类器支持向量机(SVM)进行了比较。虽然结果支持这个概念验证研究的假设,但像改进电子系统和通过更多的生物组织实验来完善方法这样的扩展仍然是未来的工作。
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引用次数: 0
The influence of infrapatellar fat pad resection on knee joint friction and damping: An in vitro study in New Zealand white rabbits 髌下脂肪垫切除对新西兰大白兔膝关节摩擦和阻尼影响的体外研究
IF 3.5 2区 医学 Q2 ENGINEERING, BIOMEDICAL Pub Date : 2026-02-01 Epub Date: 2025-11-12 DOI: 10.1016/j.jmbbm.2025.107257
Will J. Clayton , Davis R. Ballard , Amelia J. Strozier , Maryam F. Afzali , Kelly S. Santangelo , John L. Williams
The infrapatellar fat pad (IFP), an adipose tissue located in the anterior knee joint, is hypothesized to absorb shocks and aid in joint lubrication. We investigated the consequences of IFP removal on joint friction and damping in an in vitro animal model. The hindlimbs of female New Zealand white rabbits were dissected to retain the knee ligaments, joint capsule, and patellar retinaculum. Knees were mounted in a pendulum with the knee joint serving as the fulcrum while keeping the quadriceps tendon unloaded to assess joint friction and damping in each knee for three conditions: Control, Sham, and no IFP (IFP-R). Friction and damping were assessed under a 15N tibio-femoral joint load (40 % of body weight) at three flexion angles (50°, 100°, and 130°), and gyroscopic data were recorded to obtain the time decay of amplitude. Two models, a linear friction and an exponential decay friction model, were fit to the amplitude decay over time. The linear model provided Stanton's joint boundary friction coefficient (μL); the exponential decay model provided an exponential decay friction (μE) and a viscous damping (c) coefficient. When compared across all angles of testing, IFP removal decreased μL by 6 % (p = 0.0057) vs Controls (μL = 0.0217 vs 0.0230); IFP removal decreased c by 9 % (p < 0.001) vs Controls (c = 0.00262 vs 0.00239 kgm2/s) and by 6 % vs Sham (p = 0.017, c = 0.00255 vs 0.00239 kgm2/s). IFP removal did not affect μE (p = 0.12).
髌下脂肪垫(IFP)是一种位于膝关节前部的脂肪组织,被认为可以吸收冲击并帮助关节润滑。我们在体外动物模型中研究了IFP去除对关节摩擦和阻尼的影响。解剖雌性新西兰大白兔后肢,保留膝关节韧带、关节囊和髌骨支持带。在三种情况下:对照组、假手术和无IFP (IFP- r),双膝以膝关节为支点,保持股四头肌肌腱卸载,以评估每个膝关节的关节摩擦和阻尼。在三个屈曲角度(50°,100°和130°)下,在15N的胫骨-股骨关节载荷(体重的40% %)下评估摩擦和阻尼,并记录陀螺仪数据以获得振幅的时间衰减。两个模型,线性摩擦和指数衰减摩擦模型,适合振幅衰减随时间的变化。线性模型给出了斯坦顿节理边界摩擦系数(μL);指数衰减模型给出了指数衰减摩擦系数μE和粘性阻尼系数c。在所有测试角度进行比较时,与对照组(μL = 0.0217 vs 0.0230)相比,IFP去除率降低了6 μL % (p = 0.0057);奖学金项目删除c降低了9 % (p & lt; 0.001)和控制(c = 0.00262 vs 0.00239 kgm2 / s)和6 % vs骗局(p = 0.017 c = 0.00255 vs 0.00239 kgm2 / s)。去除IFP对μE无影响(p = 0.12)。
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引用次数: 0
Ex-vivo biomechanical characterization of porcine cava vein 猪腔静脉的离体生物力学特征
IF 3.5 2区 医学 Q2 ENGINEERING, BIOMEDICAL Pub Date : 2026-02-01 Epub Date: 2025-11-13 DOI: 10.1016/j.jmbbm.2025.107271
Eleonora Luzietti , Martina Schembri , Ariel F. Pascaner , Ferdinando Auricchio , Alessandro Caimi , Michele Conti
In recent years, percutaneous procedures are gradually replacing open heart surgery for the treatment of tricuspid valve pathological conditions deploying prosthetic devices (i.e., stent-graft) within the proximal portion of the cava veins. Nevertheless, since there is no comprehensive mechanical characterization of the venous district, the devices exploited in these procedures are very similar to the ones exploited in aortic treatment, involving possible critical periprocedural complications.
According to the international standards adopted for the design of novel vascular devices, this study presents an experimental set-up to investigate the biomechanics of fifteen porcine cava veins with the development of a semi-automatic protocol for compliance testing. During the tests, 2D echo images of the vessel lumen are acquired for different steps within a pressure range of 5–20 mmHg. The acquired pressure-diameter curves of the samples are then derived by a polynomial function, furthermore, the compliance values are obtained using the corresponding equations as well.
The results demonstrate that the cava vein exhibits a hyperelastic behavior, with a nonlinear relationship between pressure and diameter. At low pressures, the veins demonstrate high compliance and reduced stiffness (11.54 ± 4.76 kPa). On the contrary, when pressures exceed the normal physiological range (i.e., greater than 10 mmHg), the veins become stiffer (294.70 ± 233.00 kPa).
The developed set-up, based on an ex-vivo porcine model, proved to be a robust tool for the assessment of vein biomechanics and for preclinical benchmarking of novel venous endovascular devices.
近年来,经皮手术逐渐取代心内直视手术治疗三尖瓣病状,在腔静脉近端植入假体装置(即支架移植)。然而,由于没有全面的静脉区力学特征,这些手术中使用的设备与主动脉治疗中使用的设备非常相似,可能涉及严重的围手术期并发症。根据新型血管装置设计的国际标准,本研究建立了一个实验装置,研究了15条猪腔静脉的生物力学,并开发了一种半自动的顺应性测试方案。在测试过程中,在5-20 mmHg的压力范围内,通过不同的步骤获得血管腔的二维回声图像。然后用多项式函数推导得到试样的压力-直径曲线,并利用相应的方程求出柔度值。结果表明,腔静脉具有超弹性,压力与直径呈非线性关系。在低压下,矿脉表现出较高的顺应性和较低的刚度(11.54±4.76 kPa)。相反,当压力超过正常生理范围(即大于10mmhg)时,静脉变硬(294.70±233.00 kPa)。基于离体猪模型的开发装置被证明是静脉生物力学评估和新型静脉血管内装置临床前基准测试的强大工具。
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引用次数: 0
Protective performance of auxetic TPU pad for helmet: An investigation into design improvements for blunt impact protection 增强型TPU头盔防护垫的防护性能:钝冲击防护设计改进研究。
IF 3.5 2区 医学 Q2 ENGINEERING, BIOMEDICAL Pub Date : 2026-02-01 Epub Date: 2025-11-10 DOI: 10.1016/j.jmbbm.2025.107254
Zhouyu Shen, Yaoke Wen, Weixiao Nie, Huicheng Wang, Haoran Xu
Traditional helmet foam pads have limited energy absorption for blunt impacts, unable to meet protective needs in complex ballistic scenarios such as fragments and bullets. Auxetic (negative Poisson's ratio) materials have been tested for helmet pads, but existing studies focus mainly on low-velocity impact protection. Thus, optimizing auxetic pad structures for high-velocity impacts is essential.
In this study, lightweight expanded thermoplastic polyurethane (TPU-LW) was used as the base material, with 3D printing to fabricate pad samples. First, TPU-LW's material constitutive model was established via uniaxial tensile tests. Simulations later revealed a key issue: a single auxetic pad caused excessive skull peak stress. To solve this, an innovative “auxetic + foam” composite pad was designed, verified by 9 mm pistol bullet and 1.1 g fragment tests.
The composite pad outperformed single auxetic and foam pads in key head blunt impact indicators. Simulations showed that under high-velocity fragment impact, the helmet's maximum backface deformation (BFD) dropped to 14.50 mm, and skull peak stress was 22.7 % lower than the foam pad. Experiments indicated that under 714 m/s fragment impact, peak head pressure was only 25 kPa - far below the foam pad's 165 kPa.
This study fills the biomechanical data gap of auxetic TPU-LW in ballistic protection. The proposed composite structure provides a theoretical basis and technical solution for upgrading helmet pads from “single-material” to “composite energy-absorbing structure,” applicable to various protective helmet research and development.
传统的头盔泡沫垫对钝冲击的能量吸收有限,无法满足碎片和子弹等复杂弹道场景的保护需求。负泊松比(负泊松比)材料已被用于头盔衬垫的测试,但现有的研究主要集中在低速冲击防护上。因此,优化缓冲垫结构以应对高速撞击是至关重要的。本研究以轻质膨胀型热塑性聚氨酯(TPU-LW)为基材,采用3D打印技术制作垫样。首先,通过单轴拉伸试验建立TPU-LW材料本构模型;后来的模拟揭示了一个关键问题:一个辅助垫会导致颅骨峰值应力过大。为了解决这一问题,设计了一种创新的“消声+泡沫”复合衬垫,并通过9毫米手枪子弹和1.1 g破片试验进行了验证。复合垫块在关键的头部钝性冲击指标上优于单一助剂垫块和泡沫垫块。仿真结果表明,在高速破片冲击下,头盔的最大后面变形量(BFD)降至14.50 mm,颅骨峰值应力比泡沫垫降低22.7%。实验表明,在714 m/s破片冲击下,峰值水头压力仅为25 kPa,远低于泡沫垫的165 kPa。本研究填补了补体TPU-LW在弹道防护方面的生物力学数据空白。本文提出的复合结构为将头盔衬垫从“单一材料”升级为“复合吸能结构”提供了理论基础和技术解决方案,适用于各种防护头盔的研发。
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引用次数: 0
Stress distribution and axial force under different filing parameters during root canal preparation: An in vitro FEA and experimental study 根管预备过程中不同锉削参数下的应力分布及轴向力:体外有限元分析与实验研究。
IF 3.5 2区 医学 Q2 ENGINEERING, BIOMEDICAL Pub Date : 2026-02-01 Epub Date: 2025-11-15 DOI: 10.1016/j.jmbbm.2025.107277
Dianhao Wu , Zhixian Qiu , Yanshuang Bai , Jingchao Wang , Jie Pan

Background

Inappropriate rotational and feed speed of the rotary nickel-titanium (Ni-Ti) file can cause damage to the root canal wall. Consequently, it is essential to examine the relationships among filing parameters, file stress, and axial force to establish a dependable foundation for the selection of parameters.

Method

A 3D reconstruction of the tooth is executed utilizing CBCT images. The reaming rate of root canal filling is established at 30 % to examine the correlation between Root Canal Preparation (RCP) parameters and damage under critical situations. Utilizing the elastic-plastic model and the Johnson-Cook intrinsic model, the explicit dynamics method of ABAQUS software is employed to simulate the contact stress and axial force at varying feed speeds (1–8 mm/s) and rotational speeds (150–800 rpm). A robotic arm-based filing experimental platform is developed to conduct bionic experiments, which examine the variation of axial filing force with different parameters, and these results are compared with simulation outcomes.

Results

Increased rotational speed and decreased feed speed of the root canal file can diminish the stress and strain on the root canal. The trends and magnitudes of axial force derived from simulation and experiment at varying speeds are comparable (deviation factor = 0.15 %–25.82 %). A rotational speed higher than 350 rpm and a feed speed lower than 6 mm/s are more conducive to stable and safe filing, and the maximum axial force and the maximum stress exhibit a trend analogous.

Conclusion

This study provides a basis for the selection of filing parameters for manual and robot-assisted RCP, thereby improving the safety of clinical preparation.
背景:旋转镍钛锉的旋转和进给速度不合适会对根管壁造成损伤。因此,有必要研究锉参数、锉应力和轴向力之间的关系,为参数的选择奠定可靠的基础。方法:利用CBCT图像对牙齿进行三维重建。将根管充填的扩孔率设定为30%,考察临界情况下根管预备(RCP)参数与损伤的相关性。利用弹塑性模型和Johnson-Cook内禀模型,采用ABAQUS软件的显式动力学方法对不同进给速度(1 ~ 8 mm/s)和转速(150 ~ 800 rpm)下的接触应力和轴向力进行了仿真。开发了基于机械臂的锉削实验平台,进行了仿生实验,研究了不同参数下轴向锉削力的变化规律,并与仿真结果进行了比较。结果:提高根管锉的旋转速度,降低根管锉的进给速度,可以减小根管的应力和应变。在不同速度下,模拟和实验得到的轴向力趋势和大小具有可比性(偏差系数= 0.15% - 25.82%)。转速大于350rpm和进给速度小于6mm /s更有利于稳定安全锉削,最大轴向力和最大应力表现出类似的趋势。结论:本研究为手动和机器人辅助RCP的锉制参数选择提供依据,从而提高临床制备的安全性。
{"title":"Stress distribution and axial force under different filing parameters during root canal preparation: An in vitro FEA and experimental study","authors":"Dianhao Wu ,&nbsp;Zhixian Qiu ,&nbsp;Yanshuang Bai ,&nbsp;Jingchao Wang ,&nbsp;Jie Pan","doi":"10.1016/j.jmbbm.2025.107277","DOIUrl":"10.1016/j.jmbbm.2025.107277","url":null,"abstract":"<div><h3>Background</h3><div>Inappropriate rotational and feed speed of the rotary nickel-titanium (Ni-Ti) file can cause damage to the root canal wall. Consequently, it is essential to examine the relationships among filing parameters, file stress, and axial force to establish a dependable foundation for the selection of parameters.</div></div><div><h3>Method</h3><div>A 3D reconstruction of the tooth is executed utilizing CBCT images. The reaming rate of root canal filling is established at 30 % to examine the correlation between Root Canal Preparation (RCP) parameters and damage under critical situations. Utilizing the elastic-plastic model and the Johnson-Cook intrinsic model, the explicit dynamics method of ABAQUS software is employed to simulate the contact stress and axial force at varying feed speeds (1–8 mm/s) and rotational speeds (150–800 rpm). A robotic arm-based filing experimental platform is developed to conduct bionic experiments, which examine the variation of axial filing force with different parameters, and these results are compared with simulation outcomes.</div></div><div><h3>Results</h3><div>Increased rotational speed and decreased feed speed of the root canal file can diminish the stress and strain on the root canal. The trends and magnitudes of axial force derived from simulation and experiment at varying speeds are comparable (deviation factor = 0.15 %–25.82 %). A rotational speed higher than 350 rpm and a feed speed lower than 6 mm/s are more conducive to stable and safe filing, and the maximum axial force and the maximum stress exhibit a trend analogous.</div></div><div><h3>Conclusion</h3><div>This study provides a basis for the selection of filing parameters for manual and robot-assisted RCP, thereby improving the safety of clinical preparation.</div></div>","PeriodicalId":380,"journal":{"name":"Journal of the Mechanical Behavior of Biomedical Materials","volume":"174 ","pages":"Article 107277"},"PeriodicalIF":3.5,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145552446","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}
引用次数: 0
A parametric analysis of interbody fusion cages placement: A finite elements approach comparing lumbar lordosis of bullet and steerable banana cages 椎间融合器放置的参数分析:用有限元方法比较子弹式和可操纵香蕉式腰椎前凸
IF 3.5 2区 医学 Q2 ENGINEERING, BIOMEDICAL Pub Date : 2026-02-01 Epub Date: 2025-11-24 DOI: 10.1016/j.jmbbm.2025.107281
Ibrahim El Bojairami , Carlo Santaguida , Salim Al Rawahi , Ahmed Aoude , Mark Driscoll

Introduction

Improper cage placement during spinal interbody fusion surgeries could lead to numerous post-operative complications. Biomechanical factors of such improper placement may result in loss of lumbar lordosis, foraminal stenosis, subsidence, and altered stress distribution to the tissues adjacent to the cage.

Objective

The aim of the present study is to compare three different lumbar interbody cage designs, placed posterior, middle, and anterior, and their biomechanical effect on the aforementioned studied parameter.

Methodology

Cages and MRI-based lumbar spine models were developed using finite elements. A parametric comparative analysis was then designed to explore cage types, height, and location on lumbar lordosis, foraminal area, cage subsidence, along with normal and shear stresses resulting from each cage configuration under a 500 N compression load.

Results

First, the model was validated in light of published data. Simulated results showed that lumbar lordosis and foraminal area are inversely related. The 6-degrees bullet cage showed the highest gain in lordosis (16.5°), while it exhibited a large loss in foraminal area (34.2 mm2). Anterior placement of banana cages, however, showed the best trade-off, effectively recording a 14.5° lordosis gain, a 0.6 mm2 loss in foraminal area, a subsidence as low as 0.27 mm, and a moderate cage stress of 13.6–23.1 MPa.

Conclusions

Reported data favors banana cages for the highest lordosis gains without compromising the other explored biomechanical factors. However, it is still advised to thoroughly consider patient-specific factors at hand, possible complications of foraminal stenosis, cage migration, and endplates wear prior to choosing an appropriate cage morphology and placement.
在脊柱椎体间融合手术中,不适当的cage放置会导致许多术后并发症。这种放置不当的生物力学因素可能导致腰椎前凸、椎间孔狭窄、下陷和改变笼子附近组织的应力分布。目的本研究的目的是比较三种不同的腰椎椎体间固定架设计,放置在后路、中路和前路,以及它们对上述研究参数的生物力学影响。方法采用有限元方法建立腰椎笼和mri模型。然后设计了参数比较分析,探讨笼型、高度、腰椎前凸位置、椎间孔面积、笼下沉,以及每种笼型在500n压缩载荷下产生的正应力和剪切应力。结果首先,根据已发表的数据对模型进行验证。模拟结果表明,腰椎前凸与椎间孔面积呈负相关。6度弹笼在前凸的增益最大(16.5°),而在椎间孔面积的损失较大(34.2 mm2)。然而,香蕉笼前置表现出最好的平衡,有效地记录了14.5°的前凸增加,0.6 mm2的椎间孔面积损失,低至0.27 mm的下沉,以及13.6-23.1 MPa的适度笼应力。结论:在不影响其他生物力学因素的情况下,报告的数据支持香蕉笼获得最高的前凸增益。然而,在选择合适的cage形态和放置位置之前,仍建议彻底考虑患者的具体因素,可能的椎间孔狭窄并发症,cage移动和终板磨损。
{"title":"A parametric analysis of interbody fusion cages placement: A finite elements approach comparing lumbar lordosis of bullet and steerable banana cages","authors":"Ibrahim El Bojairami ,&nbsp;Carlo Santaguida ,&nbsp;Salim Al Rawahi ,&nbsp;Ahmed Aoude ,&nbsp;Mark Driscoll","doi":"10.1016/j.jmbbm.2025.107281","DOIUrl":"10.1016/j.jmbbm.2025.107281","url":null,"abstract":"<div><h3>Introduction</h3><div>Improper cage placement during spinal interbody fusion surgeries could lead to numerous post-operative complications. Biomechanical factors of such improper placement may result in loss of lumbar lordosis, foraminal stenosis, subsidence, and altered stress distribution to the tissues adjacent to the cage.</div></div><div><h3>Objective</h3><div>The aim of the present study is to compare three different lumbar interbody cage designs, placed posterior, middle, and anterior, and their biomechanical effect on the aforementioned studied parameter.</div></div><div><h3>Methodology</h3><div>Cages and MRI-based lumbar spine models were developed using finite elements. A parametric comparative analysis was then designed to explore cage types, height, and location on lumbar lordosis, foraminal area, cage subsidence, along with normal and shear stresses resulting from each cage configuration under a 500 N compression load.</div></div><div><h3>Results</h3><div>First, the model was validated in light of published data. Simulated results showed that lumbar lordosis and foraminal area are inversely related. The 6-degrees bullet cage showed the highest gain in lordosis (16.5°), while it exhibited a large loss in foraminal area (34.2 mm<sup>2</sup>). Anterior placement of banana cages, however, showed the best trade-off, effectively recording a 14.5° lordosis gain, a 0.6 mm<sup>2</sup> loss in foraminal area, a subsidence as low as 0.27 mm, and a moderate cage stress of 13.6–23.1 MPa.</div></div><div><h3>Conclusions</h3><div>Reported data favors banana cages for the highest lordosis gains without compromising the other explored biomechanical factors. However, it is still advised to thoroughly consider patient-specific factors at hand, possible complications of foraminal stenosis, cage migration, and endplates wear prior to choosing an appropriate cage morphology and placement.</div></div>","PeriodicalId":380,"journal":{"name":"Journal of the Mechanical Behavior of Biomedical Materials","volume":"174 ","pages":"Article 107281"},"PeriodicalIF":3.5,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145615051","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}
引用次数: 0
Biodegradable and osteoconductive sodium alginate-gelatin/amorphous magnesium phosphate 3D-printed scaffolds for craniofacial bone regeneration 可生物降解和骨导电性海藻酸钠-明胶/无定形磷酸镁3d打印颅面骨再生支架
IF 3.5 2区 医学 Q2 ENGINEERING, BIOMEDICAL Pub Date : 2026-02-01 Epub Date: 2025-11-24 DOI: 10.1016/j.jmbbm.2025.107284
Joyce R. de Souza , Igor P. Mendes Soares , Caroline Anselmi , Prabaha Sikder , Josimeri Hebling , Alexandre L.S. Borges , Eliandra S. Trichês , Marco C. Bottino
This study aimed (1) to develop and characterize 3D-printed hydrogel-based scaffolds composed of sodium alginate and gelatin containing amorphous magnesium phosphate (AMP), and (2) to evaluate the scaffolds’ biological response with alveolar bone–derived mesenchymal stem cells (aBMSCs). Hydrogel inks were prepared with sodium alginate, gelatin, calcium chloride, and varying AMP contents (0 %, 5 %, and 10 %). The scaffolds were fabricated using an extrusion-based 3D bioprinter. First, the formulated hydrogel-based inks were characterized for rheological behavior and printability. After printing, the scaffolds were assessed for morphology, chemical composition, mechanical properties, and swelling/degradation profiles. For in vitro cell-scaffold interaction, scaffolds were seeded with aBMSCs and analyzed for cell viability, matrix mineralization, and osteogenic gene expression via RT-qPCR. Statistical analysis was performed with ANOVA/Sidak or Tukey tests, with confidence intervals (α = 5 %). Rheological analysis showed that all inks exhibited shear-thinning behavior, more pronounced in AMP-containing formulations. Filament drop tests and printability assessments demonstrated filament uniformity and structural fidelity in AMP-containing inks. Morphological analysis revealed well-defined scaffold architecture with regular edges, and SEM confirmed smooth surface morphology with uniform AMP distribution. FTIR spectra displayed characteristic phosphate and polymer bands, while EDS confirmed the presence of magnesium and phosphorus in AMP-containing scaffolds. The swelling behavior increased over 24 h, and all 3D-printed scaffolds fully degraded within 35 days. All formulations supported increased cell viability over time (p ≤ 0.0092). AMP-containing scaffolds enhanced mineralized matrix deposition under osteogenic stimulation (p < 0.0001), particularly in the 10 % AMP group, and promoted upregulation of osteogenic genes (COL1A1, ALPL, and RUNX2). Clinical significance: This study demonstrated that incorporating AMP into alginate-based hydrogels combines printability, biodegradability, and osteoconductive properties. Previous AMP-containing biomaterials lacked optimization for material extrusion-based 3D printing or the synergistic combination with a gelatin-alginate network. This strategy represents an advance in the field, offering a potential biomaterial ink for the fabrication of personalized scaffolds for craniofacial bone regeneration, enabling synergistic modulation of rheology and early osteogenic stimulation.
本研究旨在(1)开发和表征含有无定形磷酸镁(AMP)的海藻酸钠和明胶组成的3d打印水凝胶支架,(2)评估支架与牙槽骨源性间充质干细胞(aBMSCs)的生物学反应。用海藻酸钠、明胶、氯化钙和不同AMP含量(0%、5%和10%)制备水凝胶油墨。支架是使用基于挤压的3D生物打印机制造的。首先,对所配制的水凝胶基油墨进行了流变性和可印刷性表征。打印后,对支架的形态、化学成分、机械性能和膨胀/降解特性进行了评估。对于体外细胞-支架相互作用,我们在支架中植入aBMSCs,并通过RT-qPCR分析细胞活力、基质矿化和成骨基因表达。统计学分析采用ANOVA/Sidak或Tukey检验,置信区间为(α = 5%)。流变分析表明,所有油墨都表现出剪切减薄行为,在含有amp的配方中更为明显。灯丝跌落测试和可印刷性评估证明了含有amp的油墨中的灯丝均匀性和结构保真度。形态学分析显示支架结构清晰,边缘规则,SEM证实表面形貌光滑,AMP分布均匀。FTIR光谱显示出磷酸盐和聚合物的特征带,EDS证实了含amp支架中镁和磷的存在。在24 h内,肿胀行为增加,所有3d打印支架在35天内完全降解。随着时间的推移,所有配方均支持细胞活力增加(p≤0.0092)。含AMP的支架在成骨刺激下增强矿化基质沉积(p < 0.0001),特别是在10% AMP组,并促进成骨基因(COL1A1, ALPL和RUNX2)的上调。临床意义:本研究表明,将AMP加入海藻酸盐基水凝胶具有可打印性、生物降解性和骨导电性。以前含有amp的生物材料缺乏基于材料挤压的3D打印优化或与明胶-海藻酸盐网络的协同组合。这一策略代表了该领域的一项进步,为颅面骨再生个性化支架的制造提供了一种潜在的生物材料链接,实现了流变学和早期成骨刺激的协同调节。
{"title":"Biodegradable and osteoconductive sodium alginate-gelatin/amorphous magnesium phosphate 3D-printed scaffolds for craniofacial bone regeneration","authors":"Joyce R. de Souza ,&nbsp;Igor P. Mendes Soares ,&nbsp;Caroline Anselmi ,&nbsp;Prabaha Sikder ,&nbsp;Josimeri Hebling ,&nbsp;Alexandre L.S. Borges ,&nbsp;Eliandra S. Trichês ,&nbsp;Marco C. Bottino","doi":"10.1016/j.jmbbm.2025.107284","DOIUrl":"10.1016/j.jmbbm.2025.107284","url":null,"abstract":"<div><div>This study aimed (1) to develop and characterize 3D-printed hydrogel-based scaffolds composed of sodium alginate and gelatin containing amorphous magnesium phosphate (AMP), and (2) to evaluate the scaffolds’ biological response with alveolar bone–derived mesenchymal stem cells (aBMSCs). Hydrogel inks were prepared with sodium alginate, gelatin, calcium chloride, and varying AMP contents (0 %, 5 %, and 10 %). The scaffolds were fabricated using an extrusion-based 3D bioprinter. First, the formulated hydrogel-based inks were characterized for rheological behavior and printability. After printing, the scaffolds were assessed for morphology, chemical composition, mechanical properties, and swelling/degradation profiles. For <em>in vitro</em> cell-scaffold interaction, scaffolds were seeded with aBMSCs and analyzed for cell viability, matrix mineralization, and osteogenic gene expression via RT-qPCR. Statistical analysis was performed with ANOVA/Sidak or Tukey tests, with confidence intervals (α = 5 %). Rheological analysis showed that all inks exhibited shear-thinning behavior, more pronounced in AMP-containing formulations. Filament drop tests and printability assessments demonstrated filament uniformity and structural fidelity in AMP-containing inks. Morphological analysis revealed well-defined scaffold architecture with regular edges, and SEM confirmed smooth surface morphology with uniform AMP distribution. FTIR spectra displayed characteristic phosphate and polymer bands, while EDS confirmed the presence of magnesium and phosphorus in AMP-containing scaffolds. The swelling behavior increased over 24 h, and all 3D-printed scaffolds fully degraded within 35 days. All formulations supported increased cell viability over time (p ≤ 0.0092). AMP-containing scaffolds enhanced mineralized matrix deposition under osteogenic stimulation (p &lt; 0.0001), particularly in the 10 % AMP group, and promoted upregulation of osteogenic genes (COL1A1, ALPL, and RUNX2). Clinical significance: This study demonstrated that incorporating AMP into alginate-based hydrogels combines printability, biodegradability, and osteoconductive properties. Previous AMP-containing biomaterials lacked optimization for material extrusion-based 3D printing or the synergistic combination with a gelatin-alginate network. This strategy represents an advance in the field, offering a potential biomaterial ink for the fabrication of personalized scaffolds for craniofacial bone regeneration, enabling synergistic modulation of rheology and early osteogenic stimulation.</div></div>","PeriodicalId":380,"journal":{"name":"Journal of the Mechanical Behavior of Biomedical Materials","volume":"174 ","pages":"Article 107284"},"PeriodicalIF":3.5,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145615052","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}
引用次数: 0
Evaluation of a universal talus implant during gait: a combined musculoskeletal and finite element modelling approach 评估通用距骨植入在步态:联合肌肉骨骼和有限元建模方法。
IF 3.5 2区 医学 Q2 ENGINEERING, BIOMEDICAL Pub Date : 2026-02-01 Epub Date: 2025-11-13 DOI: 10.1016/j.jmbbm.2025.107278
Sami Al Shweiki , Stephen J. Ferguson , Ahmed H. Hafez , Naod T. Mogos , Tao Liu , Marwan El-Rich
Universal talus implant has emerged as an innovative solution for talus bone collapse, aiming to retain the clinical benefits of custom total talus replacement while addressing its logistical drawbacks. A subject-specific combined musculoskeletal–finite element (MSK–FE) modeling framework was developed to evaluate two universal talus implant designs during dynamic gait: a purely cobalt chromium (CoCr) implant, and an implant coated with polycarbonate-urethane (PCU), both compared to the native talus. To do so, a MSK simulation of the stance phase of gait was conducted to estimate joint kinematics and joint reaction forces in the ankle complex, with a subsequent dynamic FE simulation performed to assess contact characteristics in terms of contact area and pressure, in cartilages surrounding the talus/implant. The FE model was built directly from the bone geometries of the MSK model to ensure consistency across the study. Results showed that the PCU-coated implant more closely replicated native biomechanics, while the CoCr implant produced consistently higher pressures and smaller contact regions. Normalized RMSE across gait confirmed lower deviation from the native case for the PCU-implant in most joints. These findings highlight the potential of PCU coated implants in improving contact mechanics in articular cartilage as well as the potential of the universal implant topology. This is the first study to dynamically evaluate intra-articular behaviour in all joints surrounding the talus bone during gait, and particularly by analysing the performance of universal talus implants, demonstrating the utility of a MSK-FE approach and offering valuable insights into implant performance under physiological conditions, informing future implant design.
通用距骨植入物作为距骨塌陷的创新解决方案,旨在保留自定义全距骨置换术的临床益处,同时解决其物流缺陷。开发了一种受试者特异性联合肌肉骨骼-有限元(MSK-FE)建模框架,以评估动态步态期间两种通用距骨植入设计:纯钴铬(CoCr)植入物和涂有聚碳酸酯-聚氨酯(PCU)的植入物,两者都与天然距骨进行了比较。为此,对步态的站立阶段进行MSK模拟,以估计踝关节复合体的关节运动学和关节反作用力,随后进行动态有限元模拟,以评估距骨/植入物周围软骨的接触面积和压力方面的接触特性。有限元模型是直接从MSK模型的骨几何形状建立的,以确保整个研究的一致性。结果表明,pcu包覆种植体更接近于原始生物力学,而CoCr种植体持续产生更高的压力和更小的接触区域。步态的标准化RMSE证实,大多数关节的pci -implant与本地病例的偏差较小。这些发现突出了PCU涂层植入物在改善关节软骨接触力学方面的潜力,以及通用植入物拓扑结构的潜力。这是第一个动态评估步态中距骨周围所有关节内行为的研究,特别是通过分析通用距骨植入物的性能,证明了MSK-FE方法的实用性,并为生理条件下植入物的性能提供了有价值的见解,为未来的植入物设计提供了信息。
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引用次数: 0
Negative and positive Poynting effects in tendon under simple shear 单纯剪切作用下肌腱的负、正坡印亭效应。
IF 3.5 2区 医学 Q2 ENGINEERING, BIOMEDICAL Pub Date : 2026-02-01 Epub Date: 2025-11-12 DOI: 10.1016/j.jmbbm.2025.107268
C.S. Moreira , F.S. Araújo , L.C.S. Nunes
Shear load transfer is crucial for the redistribution of internal tendon loads and to prevent excessive local stress that can lead to severe damage and injury. To better understand this transfer mechanism, it is important to know the stress state. The aim of the present study is to investigate the normal and shear stresses in tendons sheared with the shear force applied parallel to the fascicles and collagen fibers. A key novelty of the paper is the simultaneous measurement of normal and shear forces, as well as the amount of shear of tendon samples under simple shear. For the sake of simplicity, a more straightforward model is employed to describe the normal and shear behavior of tendons. Expressions were simultaneously fitted to the measured normal and shear stresses. The results reveal that the shear behavior did not exhibit any evidence of strain-stiffening, because the shear stress was approximately proportional to the amount of shear. However, compressive and tensile normal stresses, or positive and negative Poynting effects, respectively, were observed in different samples. Each tendon specimen was sheared along the orientation of the longitudinal fascicles and collagen fibers, which were maintained by random fiber networks associated with connective tissue and cross-link structures. Compressive normal stress indicates that random fiber networks did not influence the behavior or were not significant in a certain range, whereas random fiber networks contribution was more pronounced in the case of tensile normal stress. These findings suggest that the effects of random fiber networks, which can manifest over different length scales, play an important role in the state of normal stress in tendons under simple shear. Understanding how random fiber networks influence tendon mechanics could lead to better treatments for tendon injuries and help design biomimetic materials.
剪切载荷转移对于内部肌腱载荷的重新分配和防止可能导致严重损伤和损伤的过度局部应力至关重要。为了更好地理解这种传递机制,了解应力状态是很重要的。本研究的目的是研究平行于筋束和胶原纤维的剪切力对肌腱的法向应力和剪应力的影响。本文的一个关键新颖之处在于同时测量法向力和剪力,以及单剪下肌腱样品的剪切量。为了简单起见,采用了一个更直接的模型来描述肌腱的法向和剪切行为。表达式同时拟合测量的法向应力和剪应力。结果表明,由于剪切应力与剪切量近似成正比,剪切行为没有表现出应变硬化的迹象。然而,在不同的样品中分别观察到压应力和拉应力,或正坡印亭效应和负坡印亭效应。每个肌腱标本沿着纵向束和胶原纤维的方向剪切,胶原纤维由与结缔组织和交联结构相关的随机纤维网络维持。压缩法向应力表明随机纤维网络在一定范围内不影响或不显著,而在拉伸法向应力情况下,随机纤维网络的贡献更为明显。这些发现表明,随机纤维网络的影响,可以在不同的长度尺度上表现出来,在单剪下肌腱的正常应力状态中起重要作用。了解随机纤维网络如何影响肌腱力学,可以更好地治疗肌腱损伤,并有助于设计仿生材料。
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引用次数: 0
Mechanical properties of porous 3D-printed polycaprolactone: Experimental and numerical study 多孔3d打印聚己内酯的力学性能:实验和数值研究
IF 3.5 2区 医学 Q2 ENGINEERING, BIOMEDICAL Pub Date : 2026-02-01 Epub Date: 2025-09-30 DOI: 10.1016/j.jmbbm.2025.107216
Mohammad Hadi Yazdanpanah , Sadegh Rahmati , Shahrouz Yousefzadeh , Javad Akbari , Hormoz Nouraei
This study presents a systematic investigation into the porosity–strength relationships of 3D-printed polycaprolactone (PCL) to develop predictive models for the tensile behavior of porous structures intended for biomedical applications. The research investigates the impact of void geometry and porosity levels on the mechanical response under uniaxial tensile loading, utilizing Finite Element Method (FEM) simulations and Scanning Electron Microscopy (SEM) to elucidate stress distribution, plastic deformation, and fracture mechanisms. Three void geometries—circular, square, and triangular—were analyzed across porosity levels ranging from 6 % to 30 %. Circular voids demonstrated superior stress uniformity and deformation homogeneity, while square and triangular voids exhibited localized stress concentrations and earlier onset of plasticity. Increasing porosity resulted in a marked reduction in yield stress, with maximum decreases of 24 % in square voids, 23 % in triangular voids, and 15 % in circular voids. SEM analysis revealed manufacturing defects that significantly influenced deformation behavior. The adopted Elastic-Plastic numerical model showed strong agreement with experimental observations in terms of yielding force and ultimate force, presenting an error of less than 10 %. A statistical model was developed, achieving R-squared values exceeding 0.95, which enabled the reliable estimation of tensile properties within the studied porosity range. These findings offer critical insights into the mechanical optimization of porous PCL scaffolds, providing a robust framework for future design strategies in biomedical engineering.
本研究对3d打印聚己内酯(PCL)的孔隙率-强度关系进行了系统的研究,以开发用于生物医学应用的多孔结构拉伸行为的预测模型。该研究调查了孔隙几何形状和孔隙度水平对单轴拉伸载荷下力学响应的影响,利用有限元法(FEM)模拟和扫描电子显微镜(SEM)来阐明应力分布、塑性变形和断裂机制。研究人员分析了三种孔隙几何形状——圆形、方形和三角形,孔隙度从6%到30%不等。圆形孔洞表现出较好的应力均匀性和变形均匀性,而正方形和三角形孔洞表现出局部应力集中和较早的塑性。孔隙度的增加导致屈服应力显著降低,方形孔洞最大降低24%,三角形孔洞最大降低23%,圆形孔洞最大降低15%。扫描电镜分析表明,制造缺陷对变形行为有显著影响。所采用的弹塑性数值模型在屈服力和极限力方面与实验结果吻合较好,误差小于10%。建立了一个统计模型,其r平方值超过0.95,从而能够在研究的孔隙率范围内可靠地估计拉伸性能。这些发现为多孔PCL支架的力学优化提供了重要的见解,为生物医学工程的未来设计策略提供了一个强大的框架。
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引用次数: 0
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Journal of the Mechanical Behavior of Biomedical Materials
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