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Multi-scale in silico and ex silico mechanics of 3D printed cochlear implants for local drug delivery

Isaakidou, A. (author), Ganjian, M. (author), van Hoften, R. (author), Cruz Saldivar, M. (author), Leeflang, M.A. (author), Groetsch, A. (author), Wątroba, M. (author), Schwiedrzik, J. (author), Mirzaali, Mohammad J. (author), Apachitei, I. (author), Fratila-Apachitei, E.L. (author), Zadpoor, A.A. (author)

The currently available treatments for inner ear disorders often involve systemic drug administration, leading to suboptimal drug concentrations and side effects. Cochlear implants offer a potential solution by providing localized and sustained drug delivery to the cochlea. While the mechanical characterization of both the implants and their...

journal article 2024

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Curvature tuning through defect-based 4D printing

Moosabeiki, Vahid (author), Yarali, E. (author), Ghalayaniesfahani, A. (author), Callens, S.J.P. (author), van Manen, T. (author), Accardo, A. (author), Ghodrat, S. (author), Bico, José (author), Habibi, Mehdi (author), Mirzaali, Mohammad J. (author), Zadpoor, A.A. (author)

Emerging 4D printing techniques have enabled the realization of smart materials whose shape or properties can change with time. Two important phenomena play important roles in the 4D printing of shape memory polymeric materials. First, the anisotropic deformation of the printed filaments due to residual stresses can be harnessed to create out...

journal article 2024

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Bone cell response to additively manufactured 3D micro-architectures with controlled Poisson's ratio: Auxetic vs. non-auxetic meta-biomaterials

Yarali, E. (author), Klimopoulou, M. (author), David, M.K. (author), Boukany, P. (author), Staufer, U. (author), Fratila-Apachitei, E.L. (author), Zadpoor, A.A. (author), Accardo, A. (author), Mirzaali, Mohammad J. (author)

The Poisson's ratio and elastic modulus are two parameters determining the elastic behavior of biomaterials. While the effects of elastic modulus on the cell response is widely studied, very little is known regarding the effects of the Poisson's ratio. The micro-architecture of meta-biomaterials determines not only the Poisson's ratio but...

journal article 2024

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Shape-locking in architected materials through 3D printed magnetically activated joints

de Jong, P.H. (author), Salvatori, Y.S. (author), Libonati, F. (author), Mirzaali, Mohammad J. (author), Zadpoor, A.A. (author)

Shape morphing is the ability of objects to adapt to different shapes and reduce stress concentrations through increased contact area. This is a common trait of natural and engineered objects and has several applications in, among others, soft robotics and orthopedic implants. Shape morphing is achieved through flexible materials or rigid...

journal article 2023

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3D printed patient-specific fixation plates for the treatment of slipped capital femoral epiphysis: Topology optimization vs. conventional design

Moosabeiki, Vahid (author), de Winter, N. (author), Cruz Saldivar, M. (author), Leeflang, M.A. (author), Witbreuk, M. M.E.H. (author), Lagerburg, V. (author), Mirzaali, Mohammad J. (author), Zadpoor, A.A. (author)

Orthopedic plates are commonly used after osteotomies for temporary fixation of bones. Patient-specific plates have recently emerged as a promising fixation device. However, it is unclear how various strategies used for the design of such plates perform in comparison with each other. Here, we compare the biomechanical performance of 3D...

journal article 2023

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Biomechanical evaluation of additively manufactured patient-specific mandibular cage implants designed with a semi-automated workflow: A cadaveric and retrospective case study

van Kootwijk, A. (author), Jonker, B. P. (author), Wolvius, E. B. (author), Cruz Saldivar, M. (author), Leeflang, M.A. (author), Zhou, J. (author), Tümer, N. (author), Mirzaali, Mohammad J. (author), Zadpoor, A.A. (author)

Objective: Mandibular reconstruction using patient-specific cage implants is a promising alternative to the vascularized free flap reconstruction for nonirradiated patients with adequate soft tissues, or for patients whose clinical condition is not conducive to microsurgical reconstruction. This study aimed to assess the biomechanical...

journal article 2023

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A multibody kinematic system approach for the design of shape-morphing mechanism-based metamaterials

de Jong, P.H. (author), Schwab, A.L. (author), Mirzaali, Mohammad J. (author), Zadpoor, A.A. (author)

Shape-morphing structures have the ability to adapt to various target shapes, offering significant advantages for many applications. However, predicting their behavior presents challenges. Here, we present a method to assess the shape-matching behavior of shape-morphing structures using a multibody systems approach wherein the structure is...

journal article 2023

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Rational positioning of 3D-printed voxels to realize high-fidelity multifunctional soft-hard interfaces

Cruz Saldivar, M. (author), Veeger, Robin Petrus Elias (author), Tay, E.T.W.S. (author), Fenu, M. (author), Klimopoulou, M. (author), van Osch, G.J.V.M. (author), Fratila-Apachitei, E.L. (author), Doubrovski, E.L. (author), Mirzaali, Mohammad J. (author), Zadpoor, A.A. (author)

Living organisms use functional gradients (FGs) to interface hard and soft materials (e.g., bone and tendon), a strategy with engineering potential. Past attempts involving hard (or soft) phase ratio variation have led to mechanical property inaccuracies because of microscale-material macroscale-property nonlinearity. This study examines 3D...

journal article 2023

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Rational design and additive manufacturing of grain boundary-inspired, multi-architecture lattice structures

Yang, J. (author), Chen, Xiaohong (author), Sun, Yuanxi (author), Feng, Chen (author), Yang, Zheng (author), Zadpoor, A.A. (author), Mirzaali, Mohammad J. (author), Bai, Long (author)

The advent of additive manufacturing has facilitated the design and fabrication of hybrid lattice structures with multiple morphologies. These structures combine multiple distinct architectures into a single structure with an exceptional performance that far exceeds that of each constituting architecture. However, combining strut-based...

journal article 2023

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Bioinspired rational design of bi-material 3D printed soft-hard interfaces

Cruz Saldivar, M. (author), Tay, E.T.W.S. (author), Isaakidou, A. (author), Moosabeiki, Vahid (author), Fratila-Apachitei, E.L. (author), Doubrovski, E.L. (author), Mirzaali, Mohammad J. (author), Zadpoor, A.A. (author)

Durable interfacing of hard and soft materials is a major design challenge caused by the ensuing stress concentrations. In nature, soft-hard interfaces exhibit remarkable mechanical performance, with failures rarely happening at the interface. Here, we mimic the strategies observed in nature to design efficient soft-hard interfaces. We base...

journal article 2023

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Deep Learning for Size-Agnostic Inverse Design of Random-Network 3D Printed Mechanical Metamaterials

Pahlavani, H. (author), Tsifoutis-Kazolis, Kostas (author), Cruz Saldivar, M. (author), Mody, Prerak (author), Zhou, J. (author), Mirzaali, Mohammad J. (author), Zadpoor, A.A. (author)

Practical applications of mechanical metamaterials often involve solving inverse problems aimed at finding microarchitectures that give rise to certain properties. The limited resolution of additive manufacturing techniques often requires solving such inverse problems for specific specimen sizes. Moreover, the candidate microarchitectures...

journal article 2023

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Mechanisms of fatigue crack initiation and propagation in auxetic meta-biomaterials

Kolken, H.M.A. (author), Garcia, A. Fontecha (author), Plessis, A. Du (author), Meynen, A. (author), Rans, C.D. (author), Scheys, L. (author), Mirzaali, Mohammad J. (author), Zadpoor, A.A. (author)

The fatigue performance of additively manufactured auxetic meta-biomaterials made from commercially pure titanium has been studied only recently. While certain assumptions have been made regarding the mechanisms underlying their fatigue failure, the exact mechanisms are not researched yet. Here, we studied the mechanisms of crack formation...

journal article 2022

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Semi-automated digital workflow to design and evaluate patient-specific mandibular reconstruction implants

van Kootwijk, A. (author), Moosabeiki, Vahid (author), Cruz Saldivar, M. (author), Pahlavani, H. (author), Leeflang, M.A. (author), Kazemivand Niar, S. (author), Tümer, N. (author), Mirzaali, Mohammad J. (author), Zhou, J. (author), Zadpoor, A.A. (author)

The reconstruction of large mandibular defects with optimal aesthetic and functional outcomes remains a major challenge for maxillofacial surgeons. The aim of this study was to design patient-specific mandibular reconstruction implants through a semi-automated digital workflow and to assess the effects of topology optimization on the...

journal article 2022

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Deep learning for the rare-event rational design of 3D printed multi-material mechanical metamaterials

Pahlavani, H. (author), Amani, M. (author), Cruz Saldivar, M. (author), Zhou, J. (author), Mirzaali, Mohammad J. (author), Zadpoor, A.A. (author)

Emerging multi-material 3D printing techniques enables the rational design of metamaterials with not only complex geometries but also arbitrary distributions of multiple materials within those geometries, yielding unique combinations of elastic properties. However, discovering the rare designs that lead to highly unusual combinations of...

journal article 2022

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Theoretical stiffness limits of 4D printed self-folding metamaterials

van Manen, T. (author), Moosabeiki, Vahid (author), Cruz Saldivar, M. (author), Mirzaali, Mohammad J. (author), Zadpoor, A.A. (author)

4D printing of flat sheets that self-fold into architected 3D structures is a powerful origami-inspired approach for the fabrication of multi-functional devices and metamaterials. However, the opposite stiffness requirements for the folding process and the subsequent loadbearing of 3D structures impose an intrinsic limitation in designing...

journal article 2022

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Merging strut-based and minimal surface meta-biomaterials: Decoupling surface area from mechanical properties

Kolken, H.M.A. (author), Callens, S.J.P. (author), Leeflang, M.A. (author), Mirzaali, Mohammad J. (author), Zadpoor, A.A. (author)

The rational design of bone-substituting biomaterials is relatively complex because they should meet a long list of requirements for optimal performance. Meta-biomaterials are micro-architected materials that hold great promise for meeting those requirements as they offer a unique combination of mechanical, mass-transport, and biological...

journal article 2022

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Nuclear factor erythroid 2–related factor 2 (Nrf2) deficiency causes age-dependent progression of female osteoporosis

Kubo, Yusuke (author), Beckmann, Rainer (author), Pahlavani, H. (author), Cruz Saldivar, M. (author), Szymanski, Katharina (author), Leeflang, M.A. (author), Mirzaali, Mohammad J. (author), Zadpoor, A.A. (author), Wruck, Christoph Jan (author), Jahr, H. (author)

Background: Nuclear factor erythroid 2–related factor 2 (Nrf2) is a crucial transcription factor for cellular redox homeostasis. The association of Nrf2 with elderly female osteoporotic has yet to be fully described. The aim was to elucidate a potential age-dependent Nrf2 contribution to female osteoporosis in mice. Methods: Eighteen female...

journal article 2022

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Nonlinear coarse-graining models for 3D printed multi-material biomimetic composites

Cruz Saldivar, M. (author), Doubrovski, E.L. (author), Mirzaali, Mohammad J. (author), Zadpoor, A.A. (author)

Bio-inspired composites are a great promise for mimicking the extraordinary and highly efficient properties of natural materials. Recent developments in voxel-by-voxel 3D printing have enabled extreme levels of control over the material deposition, yielding complex micro-architected materials. However, design complexity, very large degrees of...

journal article 2022

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Mechanical characterization of nanopillars by atomic force microscopy

Angeloni, L. (author), Ganjian, M. (author), Nouri Goushki, M. (author), Mirzaali, Mohammad J. (author), Hagen, C.W. (author), Zadpoor, A.A. (author), Fratila-Apachitei, E.L. (author), Ghatkesar, M.K. (author)

Micro- and nano-patterns are gaining increasing attraction in several fields ranging from nanoelectronics to bioengineering. The mechanical properties of the nanostructures (nanopillars, nanotubes, nanowires, etc.) are highly relevant for many applications but challenging to determine. Existing mechanical characterization methods require...

journal article 2021

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Curvature Induced by Deflection in Thick Meta-Plates

Mirzaali, Mohammad J. (author), Ghorbani, Aref (author), Nakatani, Kenichi (author), Nouri Goushki, M. (author), Tümer, N. (author), Callens, S.J.P. (author), Janbaz, S. (author), Accardo, A. (author), Bico, José (author), Habibi, Mehdi (author), Zadpoor, A.A. (author)

The design of advanced functional devices often requires the use of intrinsically curved geometries that belong to the realm of non-Euclidean geometry and remain a challenge for traditional engineering approaches. Here, it is shown how the simple deflection of thick meta-plates based on hexagonal cellular mesostructures can be used to achieve...

journal article 2021