Quality control for 3D printing to facilitate the production of high-quality, low-cost customised medical devices
More than 500 000 medical devices are on sale in Europe, generating around €51 billion annually and accounting for one third of the market worldwide. Due to the aging population and the rise in aesthetic surgeries, the need for medical devices the growth in this market is increasing further. Millions of operations are performed for knee replacement surgery in Europe each year alone, with an average cost of around €5,500 per person.
Additive manufacturing (AM), commonly known as 3D printing, allows the fabrication of low-cost medical implants and associated surgical cutting guides specifically tailored to each patient. However, the lack of standardised and traceable measurement methods, and knowledge of the build-up of errors over the production process, restricted uptake from the medical device industry. They require SI traceable techniques to verify the quality of the product, covering the entire manufacturing chain, and meet the EU’s strict safety requirements.
This project developed traceable methodology for AM technology, assessing the performance of over 150 fabricated medical implants which were characterised using over 200 destructive and non-destructive measurements. These results were incorporated into a Good practice guide for medical x-ray computed tomography (XCT) image acquisition and analysis, including information on the use of computed tomography (CT) imaging for patients in medicine and dentistry, and recommendations on how to handle the medical images acquired.
To allow feedback to the manufacturing chain, to enable process chain corrections to be implemented, medical parts manufactured using different materials and AM technologies, were also characterised to produce a second good practice guide ‘Detection and Prevention of Geometrical Deviations in Additively Manufactured Medical Implants’.
The quantification of the build-up of errors from each part of the implantation chain, from manufacture to eventual clinical use, was examined for maxillo-facial implants, dental guides, and spinal and cranial implants. These results were incorporated in the document ‘Report on case studies: demonstrating the errors related to each manufacturing step from medical imaging to patient application’.
Results have fed into new and existing work items on standards for the use of XCT and Coordinate Measuring Machines using CT in the AM industry and incorporated into the production environment of a manufacturer of ceramic implants.
For the first time measurement traceability is available for 3D printed medical implants. This has enabled the medical technology sector to benefit from this innovative manufacturing technique, supporting an important step towards increased access to high-quality, low-cost medical devices across Europe.