scholarly journals Geometric Modeling of Cellular Materials for Additive Manufacturing in Biomedical Field: A Review

2018 ◽  
Vol 2018 ◽  
pp. 1-14 ◽  
Author(s):  
Gianpaolo Savio ◽  
Stefano Rosso ◽  
Roberto Meneghello ◽  
Gianmaria Concheri

Advances in additive manufacturing technologies facilitate the fabrication of cellular materials that have tailored functional characteristics. The application of solid freeform fabrication techniques is especially exploited in designing scaffolds for tissue engineering. In this review, firstly, a classification of cellular materials from a geometric point of view is proposed; then, the main approaches on geometric modeling of cellular materials are discussed. Finally, an investigation on porous scaffolds fabricated by additive manufacturing technologies is pointed out. Perspectives in geometric modeling of scaffolds for tissue engineering are also proposed.

Author(s):  
Jin-Hyung Shim ◽  
Jong Young Kim ◽  
Kyung Shin Kang ◽  
Jung Kyu Park ◽  
Sei Kwang Hahn ◽  
...  

Tissue engineering is an interdisciplinary field that focuses on restoring and repairing tissues or organs. Cells, scaffolds, and biomolecules are recognized as three main components of tissue engineering. Solid freeform fabrication (SFF) technology is required to fabricate three-dimensional (3D) porous scaffolds to provide a 3D environment for cellular activity. SFF technology is especially advantageous for achieving a fully interconnected, porous scaffold. Bone morphogenic protein-2 (BMP-2), an important biomolecule, is widely used in bone tissue engineering to enhance bone regeneration activity. However, methods for the direct incorporation of intact BMP-2 within 3D scaffolds are rare. In this work, 3D porous scaffolds with poly(lactic-co-glycolic acid) chemically grafted hyaluronic acid (HA-PLGA), in which intact BMP-2 was directly encapsulated, were successfully fabricated using SFF technology. BMP-2 was previously protected by poly(ethylene glycol) (PEG), and the BMP-2/PEG complex was incorporated in HA-PLGA using an organic solvent. The HAPLGA/PEG/BMP-2 mixture was dissolved in chloroform and deposited via a multi-head deposition system (MHDS), one type of SFF technology, to fabricate a scaffold for tissue engineering. An additional air blower system and suction were installed in the MHDS for the solvent-based fabrication method. An in vitro evaluation of BMP-2 release was conducted, and prolonged release of intact BMP-2, for up to 28 days, was confirmed. After confirmation of advanced proliferation of pre osteoblasts, a superior differentiation effect of the HA-PLGA/PEG/BMP-2 scaffold was validated by measuring high expression levels of bone-specific markers, such as alkaline phosphatase (ALP) and osteocalcin (OC). We show that our solvent-based fabrication is a non-toxic method for restoring cellular activity. Moreover, the HAPLGA/PEG/BMP-2 scaffold was effective for bone regeneration.


Author(s):  
L. Shor ◽  
S. Güçeri ◽  
M. Gandhi ◽  
X. Wen ◽  
W. Sun

Bone tissue engineering is an emerging field providing viable substitutes for bone regeneration. Freeform fabrication provides an effective process tool to manufacture scaffolds with complex shapes and designed properties. We developed a novel precision extruding deposition (PED) technique to fabricate composite polycaprolactone∕hydroxyapatite (PCL∕HA) scaffolds. 25% concentration by weight of HA was used to reinforce 3D scaffolds. Two groups of scaffolds having 60% and 70% porosities and with pore sizes of 450μm and 750μm respectively, were evaluated for their morphology and compressive properties using scanning electron microscopy and the mechanical testing. In vitro cell-scaffold interaction study was carried out using primary fetal bovine osteoblasts. The cell proliferation and differentiation were evaluated by Alamar Blue assay and alkaline phosphatase activity. Our results suggested that compressive modulus of PCL∕HA scaffold was 84MPa for 60% porous scaffolds and was 76MPa for 70% porous scaffolds. The osteoblasts were able to migrate and proliferate for the cultured time over the scaffolds. Our study demonstrated the viability of the PED process to fabricate PCL scaffolds having necessary mechanical property, structural integrity, controlled pore size, and pore interconnectivity desired for bone tissue engineering.


2015 ◽  
Author(s):  
Hera Wu ◽  
Shuting Lei

Hydroxyapatite, a bioactive ceramic, has been combined with biodegradable polymers to create composite three-dimensional interconnected porous scaffolds for bone graft substitutes. The materials and fabrication methods of these composite scaffolds are reviewed. The resulting mechanical and biological properties of scaffolds produced from the combination of certain materials and fabrication methods are analyzed. Requirements for a bone graft substitute and third generation scaffolds with the addition of osteoinductive and osteogenic features to composite scaffolds including biomolecule delivery and cell seeding are also introduced. Finally, the benefits of using additive manufacturing technologies to enable high level of control over the design of interconnected pore structure are discussed.


2021 ◽  
Vol 2021 ◽  
pp. 1-20 ◽  
Author(s):  
Dhinakaran Veeman ◽  
M. Swapna Sai ◽  
P. Sureshkumar ◽  
T. Jagadeesha ◽  
L. Natrayan ◽  
...  

As a technique of producing fabric engineering scaffolds, three-dimensional (3D) printing has tremendous possibilities. 3D printing applications are restricted to a wide range of biomaterials in the field of regenerative medicine and tissue engineering. Due to their biocompatibility, bioactiveness, and biodegradability, biopolymers such as collagen, alginate, silk fibroin, chitosan, alginate, cellulose, and starch are used in a variety of fields, including the food, biomedical, regeneration, agriculture, packaging, and pharmaceutical industries. The benefits of producing 3D-printed scaffolds are many, including the capacity to produce complicated geometries, porosity, and multicell coculture and to take growth factors into account. In particular, the additional production of biopolymers offers new options to produce 3D structures and materials with specialised patterns and properties. In the realm of tissue engineering and regenerative medicine (TERM), important progress has been accomplished; now, several state-of-the-art techniques are used to produce porous scaffolds for organ or tissue regeneration to be suited for tissue technology. Natural biopolymeric materials are often better suited for designing and manufacturing healing equipment than temporary implants and tissue regeneration materials owing to its appropriate properties and biocompatibility. The review focuses on the additive manufacturing of biopolymers with significant changes, advancements, trends, and developments in regenerative medicine and tissue engineering with potential applications.


2020 ◽  
pp. 030936462094971 ◽  
Author(s):  
Branko Štefanovič ◽  
Monika Michalíková ◽  
Lucia Bednarčíková ◽  
Marianna Trebuňová ◽  
Jozef Živčák

Case description: Conventional methods for producing custom prosthetic fingers are time-consuming, can be uncomfortable for the patient, and require a skilled prosthetist. The subject was a 40-year-old male with congenital absence of the thumb and related metacarpal bone on the right non-dominant hand, anomaly of the lengths of individual upper limb segments, and contracture of the elbow joint. This hand presentation made it impossible for him to perform thumb opposition, which is a very important function for common daily activities. Objective: The goal was to design an individual passive thumb prosthesis using free open-source software, 3D scanning technology, and additive manufacturing methods (i.e., fused filament fabrication). Study design: Case report. Treatment: Artificial thumb prostheses with two types of bases and fastening interfaces were designed and manufactured. One combination was chosen as the best alternative. Outcomes: The shape, positioning, firmness, and fastening of the prosthesis were compliant enough for the patient to be able to hold objects with his healthy fingers and artificial thumb. This innovative approach to fabrication of a custom thumb prosthesis provided considerable advantages in terms of custom sizing, manufacturing time, rapid production, iteration, comfort, and costs when compared to conventional methods of manufacturing a hand prosthesis. Conclusion: The methodology of designing and manufacturing a prosthetic thumb using 3D scanning and additive manufacturing technologies have been demonstrated to be adequate from a practical point of view. These technologies show potential for use in the practice of prosthetics.


Materials ◽  
2021 ◽  
Vol 14 (17) ◽  
pp. 5083
Author(s):  
Arish Dasan ◽  
Paulina Ożóg ◽  
Jozef Kraxner ◽  
Hamada Elsayed ◽  
Elena Colusso ◽  
...  

Additive manufacturing technologies, compared to conventional shaping methods, offer great opportunities in design versatility, for the manufacturing of highly porous ceramic components. However, the application to glass powders, later subjected to viscous flow sintering, involves significant challenges, especially in shape retention and in the achievement of a substantial degree of translucency in the final products. The present paper disclosed the potential of glass recovered from liquid crystal displays (LCD) for the manufacturing of highly porous scaffolds by direct ink writing and masked stereolithography of fine powders mixed with suitable organic additives, and sintered at 950 °C, for 1–1.5 h, in air. The specific glass, featuring a relatively high transition temperature (Tg~700 °C), allowed for the complete burn-out of organics before viscous flow sintering could take place; in addition, translucency was favored by the successful removal of porosity in the struts and by the resistance of the used glass to crystallization.


Author(s):  
Daniel L. Cohen ◽  
Evan Malone ◽  
Hod Lipson ◽  
Lawrence J. Bonassar

A major challenge in orthopaedic tissue engineering is the generation of cell-seeded implants with structures that mimic native tissue, both in terms of anatomic geometries and intratissue cell distributions. By combining the strengths of injection molding tissue engineering with those of Solid Freeform Fabrication (SFF), three-dimensional pre-seeded implants were fabricated without custom-tooling, enabling efficient production of patient-specific implants. The incorporation of SFF technology also enables the fabrication of geometrically complex, multiple-material implants with spatially heterogeneous cell distributions that could not otherwise be produced. Using a custom-built robotic SFF platform and gel deposition tools, alginate hydrogel was used with calcium sulfate as a crosslinking agent to produce pre-seeded living implants of arbitrary geometries. The process was determined to be sterile and viable at 94±5%. The GAG production was found to be about half that of a similarly molded samples. The compressive elastic modulus was determined to be 1.462±0.113 kPa.


Sign in / Sign up

Export Citation Format

Share Document