Nicum, Arya; (2025) The Analysis of 3D Printed Implants. Masters thesis (M.Phil), UCL (University College London).

Preview

Text Nicum_10208319_thesis.pdf Download (21MB) | Preview

Abstract

3D printing is an additive manufacturing technique which is rapidly being adopted across engineering. This is due to the benefits that 3D printing enables when comparing to conventional methods, such as design control enabling manufacturers to produce custom devices, complex structures for improved initial stability and osseointegration, and parts with differing features, all within a single step in the manufacturing workflow. Two prevalent metal-based methods of 3D printing are the metal powder-based techniques, Selective Laser Melting (SLM) and Electron Beam Melting (EBM). These methods utilise a laser or electron beam to selectively melt powder particles repeatedly layer-by-layer to form a fully dense part. However, with the speed of adoption of 3D printing, there remains several unknown impacts of final-production implants, and particularly the porous structures. The overarching aim of this thesis is to investigate the influence of these different manufacture methods on the physical features of 3D printed implants, with a particular focus on the complex porous structures specifically on 3D printed acetabular cups, and begin to consider the clinical and regulatory impacts of this new technology in orthopaedics, to ensure patient safety is maintained in this transition. To achieve this, various analysis techniques including Scanning Electron Microscopy (SEM) and Micro-Computed Tomography (Micro-CT) have been applied to characterise both custom-made and off-the-shelf 3D printed acetabular implants and their porous structures. Chapter 3 discusses the dimensional features of the struts of these structures as well as the level of porosity found in this layer. Despite the different approaches to the porous layer design between manufacturers resulting in a variation in the dimensional features, porosity was largely not statistically significant between 4 manufacturers, demonstrating that manufacturers appear to work to a shared goal (porosity varied from medians of 49% to 82%), while optimal porosity is yet to be determined. Chapter 4 investigates the presence of a known by-product of 3D printing, surface adhered particles, and found that these were present within the porous layer regardless of manufacturer and 3D printing type, and SLM exhibited twelve times the number of particles present and smaller particles than found for EBM (24.3μm and 53.8μm, respectively). The results from this report aims to provide some fundamental evidence to inform both surgeons and implant manufacturers, and also regulatory bodies on the engineering and clinical properties of 3D printed orthopaedic implants.

Download activity - last month

Export as CSVJSONXML

Download activity - last 12 months

Export as CSVXMLJSON

Downloads by country - last 12 months

Export as XMLJSONCSV

Archive Staff Only

View Item