Properties of Hyper-Elastic-Graded Triply Periodic Minimal Surfaces
Ontology highlight
ABSTRACT:
SUBMITTER:
PROVIDER: S-EPMC10707849 | biostudies-literature | 2023 Nov
REPOSITORIES: biostudies-literature
Similar Datasets
Project description:The triply periodic minimal surface (TPMS) method is a novel approach for lattice design in a range of fields, such as impact protection and structural lightweighting. In this paper, we used the TPMS formula to rapidly and accurately generate the most common lattice structure, named the body centered cubic (BCC) structure, with certain volume fractions. TPMS-based and computer aided design (CAD) based BCC lattice structures with volume fractions in the range of 10?30% were fabricated by selective laser melting (SLM) technology with Ti?6Al?4V and subjected to compressive tests. The results demonstrated that local geometric features changed the volume and stress distributions, revealing that the TPMS-based samples were superior to the CAD-based ones, with elastic modulus, yield strength and compression strength increasing in the ranges of 18.9?42.2%, 19.2?29.5%, and 2?36.6%, respectively. The failure mechanism of the TPMS-based samples with a high volume fraction changed to brittle failure observed by scanning electron microscope (SEM), as their struts were more affected by the axial force and fractured on struts. It was also found that the TPMS-based samples have a favorable capacity to absorb energy, particularly with a 30% volume fraction, the energy absorbed up to 50% strain was approximately three times higher than that of the CAD-based sample with an equal volume fraction. Furthermore, the theoretic Gibson?Ashby mode was established in order to predict and design the mechanical properties of the lattice structures. In summary, these results can be used to rapidly create BCC lattice structures with superior compressive properties for engineering applications.
| S-EPMC6317040 | biostudies-other
Project description:Three different triply periodic minimal surfaces (TPMS) with three levels of porosity within those of cancellous bone were investigated as potential bone scaffolds. TPMS have emerged as potential designs to resemble the complex mechanical and mass transport properties of bone. Diamond, Schwarz, and Gyroid structures were 3D printed in polylactic acid, a resorbable medical grade material. The 3D printed structures were investigated for printing feasibility, and assessed by morphometric studies. Mechanical properties and permeability investigations resulted in similar values to cancellous bone. The morphometric analyses showed three different patterns of pore distribution: mono-, bi-, and multimodal pores. Subsequently, biological activity investigated with pre-osteoblastic cell lines showed no signs of cytotoxicity, and the scaffolds supported cell proliferation up to 3 weeks. Cell differentiation investigated by alkaline phosphatase showed an improvement for higher porosities and multimodal pore distributions, suggesting a higher dependency on pore distribution and size than the level of interconnectivity.
| S-EPMC7656876 | biostudies-literature
Project description:The pore architecture of porous scaffolds is a critical factor in osteogenesis, but it is a challenge to precisely configure strut-based scaffolds because of the inevitable filament corner and pore geometry deformation. This study provides a pore architecture tailoring strategy in which a series of Mg-doped wollastonite scaffolds with fully interconnected pore networks and curved pore architectures called triply periodic minimal surfaces (TPMS), which are similar to cancellous bone, are fabricated by a digital light processing technique. The sheet-TPMS pore geometries (s-Diamond, s-Gyroid) contribute to a 3‒4-fold higher initial compressive strength and 20%-40% faster Mg-ion-release rate compared to the other-TPMS scaffolds, including Diamond, Gyroid, and the Schoen's I-graph-Wrapped Package (IWP) in vitro. However, we found that Gyroid and Diamond pore scaffolds can significantly induce osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs). Analyses of rabbit experiments in vivo show that the regeneration of bone tissue in the sheet-TPMS pore geometry is delayed; on the other hand, Diamond and Gyroid pore scaffolds show notable neo-bone tissue in the center pore regions during the early stages (3-5 weeks) and the bone tissue uniformly fills the whole porous network after 7 weeks. Collectively, the design methods in this study provide an important perspective for optimizing the pore architecture design of bioceramic scaffolds to accelerate the rate of osteogenesis and promote the clinical translation of bioceramic scaffolds in the repair of bone defects.
| S-EPMC9972395 | biostudies-literature
Project description:Leaf photosynthesis, coral mineralization, and trabecular bone growth depend on triply periodic minimal surfaces (TPMSs) with hyperboloidal structure on every surface point with varying Gaussian curvatures. However, translation of this structure into tissue-engineered bone grafts is challenging. This article reports the design and fabrication of high-resolution three-dimensional TPMS scaffolds embodying biomimicking hyperboloidal topography with different Gaussian curvatures, composed of body inherent β-tricalcium phosphate, by stereolithography-based three-dimensional printing and sintering. The TPMS bone scaffolds show high porosity and interconnectivity. Notably, compared with conventional scaffolds, they can reduce stress concentration, leading to increased mechanical strength. They are also found to support the attachment, proliferation, osteogenic differentiation, and angiogenic paracrine function of human mesenchymal stem cells (hMSCs). Through transcriptomic analysis, we theorize that the hyperboloid structure induces cytoskeleton reorganization of hMSCs, expressing elongated morphology on the convex direction and strengthening the cytoskeletal contraction. The clinical therapeutic efficacy of the TPMS scaffolds assessed by rabbit femur defect and mouse subcutaneous implantation models demonstrate that the TPMS scaffolds augment new bone formation and neovascularization. In comparison with conventional scaffolds, our TPMS scaffolds successfully guide the cell fate toward osteogenesis through cell-level directional curvatures and demonstrate drastic yet quantifiable improvements in bone regeneration.
| S-EPMC9564829 | biostudies-literature
Project description:The main motivation for studying damage in bone tissue is to better understand how damage develops in the bone tissue and how it progresses. Such knowledge may help in the surgical aspects of joint replacement, fracture fixation or establishing the fracture tolerance of bones to prevent injury. Currently, there are no standards that create a realistic bone model with anisotropic material properties, although several protocols have been suggested. This study seeks to retrospectively evaluate the damage of bone tissue with respect to patient demography including age, gender, race, body mass index (BMI), height, and weight, and their role in causing fracture. Investigators believe that properties derived from CT imaging data to estimate the material properties of bone tissue provides more realistic models. Quantifying and associating damage with in vivo conditions will provide the required information to develop mathematical equations and procedures to predict the premature failure and potentially mitigate problems before they begin. Creating a realistic model for bone tissue can predict the premature failure(s), provide preliminary results before getting the surgery, and optimize the design of orthopaedic implants. A comparison was performed between the proposed model and previous efforts, where they used elastic, hyper- elastic, or elastic-plastic properties. Results showed that there was a significant difference between the anisotropic material properties of bone when compared with unrealistic previous methods. The results showed that the density is 50% higher in male subjects than female subjects. Additionally, the results showed that the density is 47.91% higher in Black subjects than Mixed subjects, 53.27% higher than Caucasian subjects and 57.41% higher than Asian. In general, race should be considered during modeling implants or suggesting therapeutic techniques.
| S-EPMC8773132 | biostudies-literature
Project description:Paratroopers are highly susceptible to lower extremity impact injuries during landing. To reduce the ground reaction force (GRF), inspired by the cat paw pad and triply periodic minimal surface (TPMS), a novel type of bionic cushion sole for paratrooper boots was designed and fabricated by additive manufacturing. A shear thickening fluid (STF) was used to mimic the unique adipose tissue with viscoelastic behavior found in cat paw pads, which is formed by a dermal layer encompassing a subcutaneous layer and acts as the primary energy dissipation mechanism for attenuating ground impact. Based on uniaxial compression tests using four typical types of cubic TPMS specimens, TPMSs with Gyroid and Diamond topologies were chosen to fill the midsole. The quasi-static and dynamic mechanical behaviors of the bionic sole were investigated by quasi-static compression tests and drop hammer tests, respectively. Then, drop landing tests at heights of 40 cm and 80 cm were performed on five kinds of soles to assess the cushioning capacity and compare them with standard paratrooper boots and sports shoes. The results showed that sports shoes had the highest cushioning capacity at a height of 40 cm, whereas at a height of 80 cm, the sole with a 1.5 mm thick Gyroid configuration and STF filling could reduce the maximum peak GRF by 15.5% when compared to standard paratrooper boots. The present work has implications for the design of novel bioinspired soles for reducing impact force.
| S-EPMC9412508 | biostudies-literature
Project description:Background: The bone repair requires the bone scaffolds to meet various mechanical and biological requirements, which makes the design of bone scaffolds a challenging problem. Novel triply periodic minimal surface (TPMS)-based bone scaffolds were designed in this study to improve the mechanical and biological performances simultaneously. Methods: The novel bone scaffolds were designed by adding optimization-guided multi-functional pores to the original scaffolds, and finite element (FE) method was used to evaluate the performances of the novel scaffolds. In addition, the novel scaffolds were fabricated by additive manufacturing (AM) and mechanical experiments were performed to evaluate the performances. Results: The FE results demonstrated the improvement in performance: the elastic modulus reduced from 5.01 GPa (original scaffold) to 2.30 GPa (novel designed scaffold), resulting in lower stress shielding; the permeability increased from 8.58 × 10-9 m2 (original scaffold) to 5.14 × 10-8 m2 (novel designed scaffold), resulting in higher mass transport capacity. Conclusion: In summary, the novel TPMS scaffolds with multi-functional pores simultaneously improve the mechanical and biological performances, making them ideal candidates for bone repair. Furthermore, the novel scaffolds expanded the design domain of TPMS-based bone scaffolds, providing a promising new method for the design of high-performance bone scaffolds.
| S-EPMC11238189 | biostudies-literature
Project description:Using field-theoretic simulations based on a self-consistent field theory (SCFT) with or without finite compressibility, nanoscale mesophase formation in molten linear AB and ABC block copolymers is investigated in search of candidates for new and useful nanomaterials. At selected compositions and segregation strengths, the copolymers are shown to evolve into some new nanostructures with either unusual crystal symmetry or a peculiar morphology. There exists a holey layered morphology with Im3 symmetry, which lacks one mirror reflection compared with Im3m symmetry. Also, a peculiar cubic bicontinuous morphology, whose channels are connected with tetrapod units, is found to have Pn3m symmetry. It is shown that there is another network morphology with tripod connections, which reveals P432 symmetry. The optimized free energies of these new mesophases and their relative stability are discussed in comparison with those of double gyroids and double diamonds.
| S-EPMC6631806 | biostudies-other
Project description:Water droplet impact on surfaces is a ubiquitous phenomenon in nature and industry, where the time of contact between droplet and surface influences the transfer of mass, momentum and energy. To manipulate and reduce the contact time of impacting droplets, previous publications report tailoring of surface microstructures that influence the droplet - surface interface. Here we show that surface elasticity also affects droplet impact, where a droplet impacting an elastic superhydrophobic surface can lead to a two-fold reduction in contact time compared to equivalent rigid surfaces. Using high speed imaging, we investigated the impact dynamics on elastic nanostructured superhydrophobic substrates having membrane and cantilever designs with stiffness 0.5-7630 N/m. Upon impact, the droplet excites the substrate to oscillate, while during liquid retraction, the substrate imparts vertical momentum back to the droplet with a springboard effect, causing early droplet lift-off with reduced contact time. Through detailed experimental and theoretical analysis, we show that this novel springboarding phenomenon is achieved for a specific range of Weber numbers (We >40) and droplet Froude numbers during spreading (Fr >1). The observation of the substrate elasticity-mediated droplet springboard effect provides new insight into droplet impact physics.
| S-EPMC4962083 | biostudies-literature
Project description:Finding alternative strategies for the regeneration of craniofacial bone defects (CSD), such as combining a synthetic ephemeral calcium phosphate (CaP) implant and/or active substances and cells, would contribute to solving this reconstructive roadblock. However, CaP's architectural features (i.e., architecture and composition) still need to be tailored, and the use of processed stem cells and synthetic active substances (e.g., recombinant human bone morphogenetic protein 2) drastically limits the clinical application of such approaches. Focusing on solutions that are directly transposable to the clinical setting, biphasic calcium phosphate (BCP) and carbonated hydroxyapatite (CHA) 3D-printed disks with a triply periodic minimal structure (TPMS) were implanted in calvarial critical-sized defects (rat model) with or without addition of total bone marrow (TBM). Bone regeneration within the defect was evaluated, and the outcomes were compared to a standard-care procedure based on BCP granules soaked with TBM (positive control). After 7 weeks, de novo bone formation was significantly greater in the CHA disks + TBM group than in the positive controls (3.33 mm3 and 2.15 mm3, respectively, P=0.04). These encouraging results indicate that both CHA and TPMS architectures are potentially advantageous in the repair of CSDs and that this one-step procedure warrants further clinical investigation.
| S-EPMC7064275 | biostudies-literature