Additive manufacture (AM) of patient specific implants is rapidly growing across healthcare sectors. The versatility of AM has allowed for precise surgical planning and the generation of implants that accurately conform to the patient’s defect anatomy with minimal site preparation. In particular the musculoskeletal field has been a early adopter of these bespoke devices. Given that titanium alloys are the predominant material used for bone prosthetics the most clinically relevant AM technique are those capable of processing metal feedstock. The most commonly used is power bed fusion (PBF), a process that employs a laser to melt powdered particles together selectively in a layer-by-layer manner. Beyond enabling bulk customisation of the implant geometry, it is possible to create structures via PBF with intricate design features that exhibit functional advantages. For example, several medical devices exploit the tuneability of porous lattice structures to facilitate bone ingrowth while also matching the mechanical properties of the implant to the surrounding tissue, which has been shown to encourage regeneration.
It is important to recognise that there is typically significant post-manufacturing processing of PBF devices before use in healthcare applications. Particular attention is given to removal of any loose powder that is not fully melted during manufacture since this may cause adverse biological responses. Many implants also require polishing to a low surface roughness. However, with the growing use of intricate featured devices, such as lattices this is an increasing challenge within the AM field. Currently there are many design rules that have been developed for the AM process itself but more work is needed to establish how to optimise device topology for these up-stream finishing processes. This is a critical area of development to enable the full benefits of AM within the healthcare sector.
This project will seek to better understand the common post-manufacturing routes applied for bone prosthetics produced via PBF. From this collective understanding a framework of design rules will be developed and validated to ensure adequate cleaning of such implants in a reproducible manner. A multidisciplinary approach will be taken including use of topological optimisation, design of experiments, and conducting in-vitro testing to demonstrate the effectiveness of the proposed approach.
The position is funded for 3.5 years jointly between the University of Birmingham and the MTC (https://www.the-mtc.org/). We are looking for a candidate with a minimum of a 2:1 degree in a related Engineering / Scientific subject area. The successful candidate should have a passion for technology development, be an effective communicator, self driven and a team player. It would be advantageous to have previous experience with AM, computer aided design or medical device development.