Porous tantalum structures for bone implants: Fabrication, mechanical and in vitro biological properties

Abstract

Relatively high cost of manufacturing and inability to produce modular all tantalum implants has limited its widespread acceptance, in spite of its excellent in vitro and in vivo biocompatibility. In this article, we report how to process Ta to create net shape porous structures with varying porosity using Laser Engineered Net Shaping (LENS™) for the first time. Porous Ta samples with relative densities between 45 to 73% have been successfully fabricated and characterized for their mechanical properties. In vitro cell materials interactions, using human osteoblast cell line hFOB, have been accessed on these porous Ta structures and compared with porous Ti control samples. The results show that the Young's modulus of porous Ta can be tailored between 1.5 to 20 GPa by changing the pore volume fraction between 27 and 55%. In vitro biocompatibility in terms of MTT assay and immunochemistry study showed excellent cellular adherence, growth and differentitation with abundant extracellular matrix formation on porous Ta structures compared to porous Ti control. These results indicate that porous Ta structures can promote enhanced/early biological fixation. The enhanced in vitro cell-materials interactions on porous Ta surface are attributed to chemistry and its high wettability and surface energy relative to porous Ti. Our results show that these laser processed porous Ta structures can find numerous applications, particularly among older patients, for metallic implants because of their excellent bioactivity.

Trabecular Metal in Total Knee Arthroplasty Associated with Higher Knee Scores: A Randomized Controlled Trial

“…It has excellent mechanical and biological properties [6,36,68], including primary stability and osseointegration. As reported in clinical studies, this has resulted in excellent early performance of primary implants of this material [14,20,22,23,30,41,45,59,63,67].…”

Introductory Chapter: Multi-Aspect Bibliographic Analysis of the Synergy of Technical, Biological and Medical Sciences Concerning Materials and Technologies Used for Medical and Dental Implantable Devices

“…Such technologies can be applied for various engineering materials, not only metals and alloys which are prepared, respectively, as powder or liquid, rolled material or thin fibres. Additive technologies have been widely used for fabricating diverse, customised elements applied in medicine, in particular, scaffolds with required porosity and strength with living cells implanted into an organism [225][226][227], models of implants and dental bridges [228][229][230], implants of individualised implants of the upper jaw bone, hip joint and skull fragments [231][232][233][234][235][236][237][238]. Considering the additive technologies applied most widely, the following have found their application for scaffold manufacturing, in implantology and prosthetics, i.e., electron beam melting (EBM) [222,[239][240][241][242][243], and also 3D printing for production of indirect models, although selective laser sintering/selective laser melting (SLS/SLM) and its technological variants offers broadest opportunities [220,222,[244][245][246][247][248][249][250][251][252][253], which was noted in discussing each group of materials.…”

Metallic materials for 3D printing

“…Pure metals processed through metal 3D printing include titanium processed through LS, 26 LM, 27 and LMD, 27 , 28 tantalum through LMD, 29 gold through SLM, 30 copper through LM and EBM, 31 , 32 and iron and niobium through EBM.…”