scispace - formally typeset
Journal ArticleDOI: 10.1007/S11665-021-05566-X

Mechanical Reliability and In Vitro Bioactivity of 3D-Printed Porous Polylactic Acid-Hydroxyapatite Scaffold

04 Mar 2021-Journal of Materials Engineering and Performance (Springer US)-Vol. 30, Iss: 7, pp 4946-4956
Abstract: The study aimed to investigate the mechanical reliability and in vitro bioactivity of the three-dimensional (3D) printed hydroxyapatite (HA) reinforced polylactic acid (PLA) porous scaffolds. The experiments have been performed to study the effect of HA wt.% in PLA matrix, infill density, and post-printing thermal-stimulus on the flexural and compressive strength. Next to this, the best combination of input parameters, in-response of the observed mechanical properties, was determined to print the test specimens for the analysis of reliability, through Weibull distribution. Further, the fracture morphology of the developed PLA/HA porous scaffolds has been investigated, using scanning electron microscopy, to observe the involved fracture mechanism. Moreover, the in vitro cell-culture with osteoblastic bone marrow mesenchymal stem cells-lines has been studied after 1, 3, and 7 days of seeding. The results of the study highlighted that the processing parameters have a strong impact on the mechanical properties of the 3D printed porous scaffolds. Further, the in vitro analysis showed excellent growth, proliferation, and differentiation of osteoplastic cells. Along with these, the result of the Weibull distribution advocated that the printed porous scaffolds are mechanically reliable. Overall, the present study unequivocally advocates that the 3D printed PLA/HA scaffold can be used for potential tissue engineering and biomedical applications.

... read more

Topics: Polylactic acid (52%)
Citations
  More

14 results found


Journal ArticleDOI: 10.1016/J.MATPR.2021.06.216
Abstract: Fused Deposition Modelling is a fast emerging technology due to its capacity to generate usable components with multiple geometrical designs in a fair period of time without the usage of any tooling or human interaction. The features and reliability of FDM fabricated parts are highly dependent on a small number of processing variables and their settings. The current study examines the relationship between five significant processing constraints. i.e. raster angle, part orientation, air gap, layer thickness and raster width and what effect do they have on the dimensional accuracy of the fabricated part. Twenty-seven experiments were piloted and configured using Taguchi’s architecture and recently formulated MARCOS Method. Here, the Genetic Algorithm Optimization, Simulated Annealing Algorithm Optimization, Particle Swarm Optimization, Grey-Wolf Optimization Algorithm, Moth Flame Optimization Algorithm, Whale Optimization Algorithm, Jaya Algorithm Optimization, Sunflower Optimization Algorithm, Lichtenberg Algorithm Optimization and Forensic Based Investigation Optimization approaches as ten different optimizations have been utilized to predict the optimal setting of the experiment. A comparative inspection of these nature-inspired algorithms in FDM printed part was performed in this study which reported part orientation as the most significant element.

... read more

7 Citations


Journal ArticleDOI: 10.1016/J.MATPR.2021.03.665
Danish Raza1, Gautam Kumar1, Mohammad Uzair1, Muna Kumar Singh1  +2 moreInstitutions (1)
Abstract: In the current study, the latest class of titanium alloy β-phase (Ti-Nb-Ta-Zr) using orthopaedic device vacuum arc melting methods. The alloy is repeatedly melted to strengthen its homogeneity. To ensure homogeneity, the s-phase Ti-Nb-Ta-Zr alloy was replenished 4 times using the electric arch. The analysis of the β-phase as-developed titanium alloy's microstructure, elemental and phase composition was examined. Vickers Micro-hardness tester and a universal testing machine have calculated the micro-hardness and tensile strength of the formed β-phase titanium alloy (UTM, BIS). The metastatic β-Phase alloy with a coarse kernel range of ~ 250 μm was found in the micro-structure study. The crystallographic analysis revealed that the metastable 'β' stage in the matrix was β-TNTZ alloy. The mechanical properties include the 590 MPa train strength (UTS) with an elongation of 13.47 percent, and are smaller than those in Ti-6Al-4 V alloy and SS-316L with a 55 MPa young modulus near the cortical bone (approximately 10-30GPa). The surface properties were improved after heat treatment. The mechanical properties of β-Ti alloy relative to other titanium alloys for biomedical application.

... read more

Topics: Titanium alloy (64%), Alloy (59%), Ultimate tensile strength (52%) ... read more

2 Citations


Journal ArticleDOI: 10.1016/J.MATPR.2021.09.049
Abstract: The gap between demand and supply for the required bone graft and donor is widening day by day. Tissue engineering approach is used to overcome the limitations of bone graft substitutes. In Tissue Engineering, a biocompatible scaffold is placed inside the body, which over a period of time gets converted into the bone Extra-Cellular Matrix (ECM). Hydroxyapatite (HA) and β-Tricalcium Phosphate (β-TCP) are extensively studied to fabricate bone scaffolds for tissue engineering applications by conventional methods. However, the scaffold needs to be produced with controlled pore size, porosity, and pore interconnectivity for homing of the cells which can be achieved by additive manufacturing. Also, the scaffolds produced with conventional methods lack mechanical properties which limit the use of hydroxyapatite (HA) and β-tricalcium phosphate (β-TCP) at the recipient site. In this paper, scaffolds with different materials' compositions, different layers orientations, and pore sizes are designed as an input parameter for different scaffold architecture which has not been previously studied considering extrusion-based additive manufacturing. These parameters are considered to predict the mechanical properties of the scaffold architecture. It has been found that in all combinations the scaffold with 0°- 90°- 0°- 90° orientation layer gives Young’s modulus that is comparable to natural human bone. However, the scaffolds with 0°- 90° -0°- 90° orientation layer and 350 µm pore size gives comparatively higher effective Young’s modulus of about 30.948 GPa for 5% HA composition. In the future 0°- 90°- 0°- 90° orientation can be considered to fabricate 3D scaffold architecture using extrusion-based additive manufacturing method.

... read more

Topics: Scaffold (53%)

1 Citations


Journal ArticleDOI: 10.1016/J.MATPR.2021.09.433
Abstract: Fused Deposition Modelling (FDM) is an additive manufacturing technique that is widely used for the fabrication and prototyping of parts and objects of different shapes and geometries. Several research and tests have been carried out over the past two decades concerning materials used and applications of the FDM process. Very few articles highlighted machine parameters associated with FDM. This article reviews the materials and machine parameters associated with FDM printing and highlights the effect of the mechanical and thermal properties of the material on the durability and strength of the printed objects. Machine parameters such as layer resolution, build orientation, raster angle, flow rate and speed, nozzle, platform temperature, and the air–gap formation in specimens of different materials have been discussed. This article provides an overview to researchers about the different process parameters involved, the applications of FDM 3D printed parts in various domains, and what the future holds for this technology.

... read more

1 Citations


Journal ArticleDOI: 10.1016/J.MATPR.2021.09.017
K. Sunitha1, Hitesh Vasudev1Institutions (1)
Abstract: In the fabrication of equipment and device components that require surface qualities such as corrosion, oxidation and wear resistance, metal surface coating is an efficient and secure method. The main purpose of the coating application could be decorative, functional, or both. Functional coating can be used forimproving surface properties for example wear resistance, oxidation, corrosion, and adhesion. In contrast, cosmetic coatings, such as paints by designers, have been applied to render the product/material more desirable. Nowadays, various coating methods are being implemented to obtain the required practical or cosmetic properties. Some of the most effective and desirable approaches for preserving/protecting fresh machine parts from tear, heat corrosion and oxidation is the thermal spray coating technique. A concise description of the various spraying methods, their basic concepts, disadvantages and implementations is included in this article. In addition to these characteristics, the properties of the coating processes and the various methods used to avoid corrosion are easily identified.

... read more

Topics: Coating (71%), Surface coating (68%), Corrosion (53%)

1 Citations


References
  More

57 results found


Journal ArticleDOI: 10.1016/J.MSER.2014.04.001
Shuilin Wu1, Xiangmei Liu1, Kelvin W.K. Yeung2, Changsheng Liu3  +2 moreInstitutions (4)
Abstract: Increased use of reconstruction procedures in orthopedics, due to trauma, tumor, deformity, degeneration and an aging population, has caused a blossom, not only in surgical advancement, but also in the development of bone implants. Traditional synthetic porous scaffolds are made of metals, polymers, ceramics or even composite biomaterials, in which the design does not consider the native structure and properties of cells and natural tissues. Thus, these synthetic scaffolds often poorly integrate with the cells and surrounding host tissue, thereby resulting in unsatisfactory surgical outcomes due to poor corrosion and wear, mechanical mismatch, unamiable surface environment, and other unfavorable properties. Musculoskeletal tissue reconstruction is the ultimate objective in orthopedic surgery. This objective can be achieved by (i) prosthesis or fixation device implantation, and (ii) tissue engineered bone scaffolds. These devices focus on the design of implants, regardless of the choice of new biomaterials. Indeed, metallic materials, e.g. 316L stainless steel, titanium alloys and cobalt chromium alloys, are predominantly used in bone surgeries, especially in the load-bearing zone of prostheses. The engineered scaffolds take biodegradability, cell biology, biomolecules and material mechanical properties into account, in which these features are ideally suited for bone tissue repair and regeneration. Therefore, the design of the scaffold is extremely important to the success of clinical outcomes in musculoskeletal surgeries. The ideal scaffolds should mimic the natural extracellular matrix (ECM) as much as possible, since the ECM found in natural tissues supports cell attachment, proliferation, and differentiation, indicating that scaffolds should consist of appropriate biochemistry and nano/micro-scale surface topographies, in order to formulate favorable binding sites to actively regulate and control cell and tissue behavior, while interacting with host cells. In addition, scaffolds should also possess a similar macro structure to what is found in natural bone. This feature may provide space for the growth of cells and new tissues, as well as for the carriers of growth factors. Another important concern is the mechanical properties of scaffolds. It has been reported that the mechanical features can significantly influence the osteointegration between implants and surrounding tissues, as well as cell behaviors. Since natural bone exhibits super-elastic biomechanical properties with a Young's modulus value in the range of 1–27 GPa, the ideal scaffolds should mimic strength, stiffness and mechanical behavior, so as to avoid possible post-operation stress shielding effects, which induce bone resorption and consequent implant failure. In addition, the rate of degradation and the by-products of biodegradable materials are also critical in the role of bone regeneration. Indeed, the mechanical integrity of a scaffold will be significantly reduced if the degradation rate is rapid, thereby resulting in a pre-matured collapse of the scaffold before the tissue is regenerated. Another concern is that the by-products upon degradation may alter the tissue microenvironment and then challenge the biocompatibility of the scaffold and the subsequent tissue repair. Therefore, these two factors should be carefully considered when designing new biomaterials for tissue regeneration. To address the aforementioned questions, an overview of the design of ideal biomimetic porous scaffolds is presented in this paper. Hence, a number of original engineering processes and techniques, including the production of a hierarchical structure on both the macro- and nano-scales, the adjustment of biomechanical properties through structural alignment and chemical components, the control of the biodegradability of the scaffold and its by-products, the change of biomimetic surface properties by altering interfacial chemistry, and micro- and nano-topographies will be discussed. In general, the concepts and techniques mentioned above provide insights into designing superior biomimetic scaffolds for bone tissue engineering.

... read more

Topics: Bone regeneration (61%), Bone tissue (58%), Tissue engineering (55%) ... read more

660 Citations


Open accessJournal ArticleDOI: 10.1038/SREP23058
Ryosuke Matsuzaki1, Masahito Ueda2, Masaki Namiki2, Tae Kun Jeong2  +5 moreInstitutions (4)
11 Mar 2016-Scientific Reports
Abstract: We have developed a method for the three-dimensional (3D) printing of continuous fiber-reinforced thermoplastics based on fused-deposition modeling. The technique enables direct 3D fabrication without the use of molds and may become the standard next-generation composite fabrication methodology. A thermoplastic filament and continuous fibers were separately supplied to the 3D printer and the fibers were impregnated with the filament within the heated nozzle of the printer immediately before printing. Polylactic acid was used as the matrix while carbon fibers, or twisted yarns of natural jute fibers, were used as the reinforcements. The thermoplastics reinforced with unidirectional jute fibers were examples of plant-sourced composites; those reinforced with unidirectional carbon fiber showed mechanical properties superior to those of both the jute-reinforced and unreinforced thermoplastics. Continuous fiber reinforcement improved the tensile strength of the printed composites relative to the values shown by conventional 3D-printed polymer-based composites.

... read more

Topics: Fiber (58%), Thermoplastic (51%)

504 Citations


Journal ArticleDOI: 10.1016/J.JMBBM.2015.11.036
Fedor Senatov1, K.V. Niaza1, M.Yu. Zadorozhnyy1, A.V. Maksimkin1  +2 moreInstitutions (1)
Abstract: In the present work polylactide (PLA)/15wt% hydroxyapatite (HA) porous scaffolds with pre-modeled structure were obtained by 3D-printing by fused filament fabrication. Composite filament was obtained by extrusion. Mechanical properties, structural characteristics and shape memory effect (SME) were studied. Direct heating was used for activation of SME. The average pore size and porosity of the scaffolds were 700μm and 30vol%, respectively. Dispersed particles of HA acted as nucleation centers during the ordering of PLA molecular chains and formed an additional rigid fixed phase that reduced molecular mobility, which led to a shift of the onset of recovery stress growth from 53 to 57°C. A more rapid development of stresses was observed for PLA/HA composites with the maximum recovery stress of 3.0MPa at 70°C. Ceramic particles inhibited the growth of cracks during compression-heating-compression cycles when porous PLA/HA 3D-scaffolds recovered their initial shape. Shape recovery at the last cycle was about 96%. SME during heating may have resulted in "self-healing" of scaffold by narrowing the cracks. PLA/HA 3D-scaffolds were found to withstand up to three compression-heating-compression cycles without delamination. It was shown that PLA/15%HA porous scaffolds obtained by 3D-printing with shape recovery of 98% may be used as self-fitting implant for small bone defect replacement owing to SME.

... read more

244 Citations


Open accessJournal ArticleDOI: 10.1038/SREP24224
Jiangtao Wu1, Chao Yuan2, Zhen Ding3, Michael Isakov1  +4 moreInstitutions (3)
13 Apr 2016-Scientific Reports
Abstract: Recent research using 3D printing to create active structures has added an exciting new dimension to 3D printing technology. After being printed, these active, often composite, materials can change their shape over time; this has been termed as 4D printing. In this paper, we demonstrate the design and manufacture of active composites that can take multiple shapes, depending on the environmental temperature. This is achieved by 3D printing layered composite structures with multiple families of shape memory polymer (SMP) fibers – digital SMPs - with different glass transition temperatures (Tg) to control the transformation of the structure. After a simple single-step thermomechanical programming process, the fiber families can be sequentially activated to bend when the temperature is increased. By tuning the volume fraction of the fibers, bending deformation can be controlled. We develop a theoretical model to predict the deformation behavior for better understanding the phenomena and aiding the design. We also design and print several flat 2D structures that can be programmed to fold and open themselves when subjected to heat. With the advantages of an easy fabrication process and the controllable multi-shape memory effect, the printed SMP composites have a great potential in 4D printing applications.

... read more

Topics: Shape-memory polymer (53%), 3D printing (51%)

226 Citations


Journal ArticleDOI: 10.1007/S00170-015-7843-2
Yang Yang1, Yonghua Chen1, Ying Wei1, Yingtian Li1Institutions (1)
Abstract: This article presents a novel method of shape memory polymer (SMP) processing for additive manufacturing, in particular, fused-deposition modeling (FDM). Critical extrusion process parameters have been experimented to determine an appropriate set of parameter values so that good-quality SMP filament could be made for FDM. In the FDM process, effects of different printing parameters such as extruder temperature and scanning speed on object printing quality are also studied. In all the process studies, we aim to achieve good-quality parts by evaluating part density, tensile strength, dimensional accuracy, and surface roughness. Based on these studies, sample SMP models have been successfully built. Due to the thermal sensitive nature of the printed SMP parts, they can potentially be used as fasteners in active assembly/disassembly, smart actuators, deployable structures for aero-space applications, etc.

... read more

178 Citations