Next Generation Biomaterials : Next Generation Biomaterials II
Sponsored by: ACerS Bioceramics Division, TMS Biomaterials Committee
Program Organizers: Roger Narayan, University of North Carolina; David Dausch, RTI International; Sanjiv Lalwani, Lynntech, Inc.
Monday 2:00 PM
November 2, 2020
Room: Virtual Meeting Room 12
Location: MS&T Virtual
Session Chair: Soshu Kirihara, Osaka University; Min Wang, University of Hong Kong; Christos Softas, University of Birmingham
2:00 PM Invited
Nanostructured Surface Bioactive Composite Scaffold for Filling of Mandibular Bone Defects: A Pilot Study: Leonardo Ciocca1; Claudio Marchetti1; Achille Tarsitano1; 1University of Bologna
Purpose: The aim of this study was to investigate the chemical and physical surface properties of a hybrid nano-hydroxyapatite/collagen/polycaprolactone (nHA/Coll/PCL) material, and to test its in vitro biocompatibility and in vivo osseointegration. Methods: The material was characterized and the biocompatibility was tested using human mesenchymal stem cells, hepatocyte carcinoma and primary osteogenic sarcoma cells. In addition, the ability of this material to fill three-wall bony defects was tested in the mandible of a sheep, simulating a maxillofacial defect after ablative cancer surgery. Results: The material confirmed a good homogeneity of the composite HA-coll-PCL, with mineralized fibers of collagen with nano HA. Human bone-marrow mesenchymal stem cells on the surface scaffold showed high metabolic activity and a high rate of viability. Biocompatibility complementary testing demonstrated no significant cytotoxicity. Histological analysis of the in-vivo experimentation showed osteointegration of the material and the absence of inflammatory cells at the bone–scaffold interface.
2:20 PM Invited
4D Printing of Advanced Scaffolds with Controlled Growth Factor Delivery for Tissue Engineering: Min Wang1; 1University of Hong Kong
4D printing, which uses 3D printing technologies to make shape-morphing objects, is increasingly explored for different industries. Objects made by 4D printing can meet the demanding requirements in particularly applications. Their shape, property and functionality can evolve with time in predefined and programmable designs. 3D printing is extensively investigated for fabricating tissue engineering scaffolds as it has many advantages and can produce multilayered scaffolds with different layer characteristics. Most human body tissues are complex and hierarchical and their regeneration requires structurally complex scaffolds that resemble tissue structures and can provide biochemical cues such as growth factors (GFs). Incorporating GFs and even live cells in scaffolds can greatly facilitate tissue regeneration. This talk will give an overview of our work in 3D/4D printing of scaffolds for regenerating tissues such as bone and blood vessels. It will focus on the design and 4D printing of shape-morphing and GF-delivering scaffolds for tissue engineering.
2:40 PM Invited
Creating Smart Biopolymer Fibers for Healthcare Applications: Ayda Afshar1; Mohan Edirisinghe1; 1University College London
Biopolymers have been identified as a promising class of materials with a wide variety of applications, outstanding for healthcare. Although innovative technologies are emerging, there is a huge demand for new innovations to meet current needs of healthcare. Pressurised gyration can be used to fabricate nano to microfibers which can deliver a high production yield and is an effective deposition of functional fibers suitable for wound healing and bone tissue regeneration. The key factor has been the production of a new generation of advanced biomaterials for wound healing. For example, nanofibers incorporated with antimicrobial peptides is highly desired. This has resulted in some remarkable advancements and promising healthcare capabilities e.g. reduction of Staphylococcus epidermidis at wound sites and rapid peptide release, with enhanced healing process. Meanwhile, microfiber structure is tailored by additions including nano-clays for bone regeneration. Findings have shown a significant increase in cell viability, proliferation and bone growth.
3:00 PM Invited
Stereolithographic Additive Manufacturing of Bioceramic Implants: Soshu Kirihara1; 1Osaka University
Bulky ceramic components including dendritic networks were fabricated by stereolithographic additive manufacturing. 2D cross sectional patterns were created through photo polymerization by ultra violet laser drawing on a spread resin paste including ceramic nanoparticles, and 3D composite models were sterically printed by layer lamination through chemical bonding. Photo sensitive acrylic resins with hydroxyapatite of 3 μm in particle diameter at 50 vol. % were spread on a glass substrate with 10 μm in layer thickness. An ultraviolet laser beam of 355 nm in wavelength was adjusted from 10 to 100 μm in variable diameter and scanned. Irradiation power was changed automatically from 10 to 200 mW to obtain enough solidification depth for layer by layer joining. Cross sectional patterns were laminated to create solid objects.
3:20 PM Invited
New Materials for Medical Implants: Diamond: Kate Fox1; 1RMIT University
As medical implants become more and more sophisticated, new materials are being investigated to improve the bond between the implant and the bone/tissue. We have recently developed three methods in combine diamond with additive manufacturing. 1. A polycrystalline diamond coating technology 2. A nanodiamond coating technology 3. A hybrid co-printed diamond technologyThe evidence from our studies suggest that the surface provides a good biomedical scaffold. Here we discuss our research findings that show that diamond implants promote cellular vitality, decrease bacteria attachment and be suitable for potential in situ imaging.
3:40 PM Invited
Photopolymerization-Based 3D Printing of Medical Devices: Roger Narayan1; 1University of North Carolina
Recent advances in photopolymerization-based 3D printing technologies for processing microstructured and nanostructured medical devices will be considered. A 3D printing processing approach known as two photon polymerization has been used for selective polymerization of many types of acrylate-based photosensitive resins. Polymerization of structures with microscale and nanoscale features can be obtained since multiphoton absorption exhibits a nonlinear relationship with the incident light intensity. We have used two photon polymerization used to create several types of medical devices with microscale and nanoscale features out of photosensitive polymers and organically-modified ceramic materials. The results of materials testing and application-specific device testing, including in vitro and in vivo studies, will be discussed.
4:00 PM Invited
Three High Entropy Alloys and their Ability to Control Biofilm Formation: Hideyuki Kanematsu1; David Kemény2; Eva Fazakas2; Attila Szabo3; Dana Barry4; Nobumitsu Hirai1; Akiko Ogawa1; Takeshi Kogo1; Noriyuki Wada1; Hidemi Nakamura5; Paul McGrath6; 1National Institute of Technology (KOSEN), Suzuka College; 2Budapest University of Technology and Economics; 3University of Dunaújváros; 4Clarkson University/SUNY Canton; 5National Institute of Technology, Nara College; 6Clarkson University
Biofilms are thin, inhomogeneous film-like matter that form on materials’ surfaces as a result of bacterial activities. They cause many problems like slime and scale buildup in pipes, corrosion of structures, food contamination, the spread of disease, etc. Since the substrate material is one of the important factors affecting biofilm formation, the development of new alloys (for substrates) is a promising countermeasure. In this study, we focused on three kinds of high entropy alloys: 16%Al-16%Ti-16%Ni-16%Cu-16%Ag-16%Sn, 20%Al-20%Ti-20%Ni-20%Cu-20%Fe and 22.5%Al-22.5%Ti-20%Ni-20%Cu-20%Fe. These alloys were all immersed into wells containing liquid cultures with bacteria. Later, the alloys were removed and checked / evaluated by Raman Spectroscopy and crystal violet staining methods to determine the biofilm formation capability of the samples. The results were noted and compared. Differences among specimens were also analyzed to provide useful information about their ability to control biofilm formation.