Nanoscience and nanoscale analysis of advanced materials have many times proven to be the key analytical approach in materials synthesis and materials analysis. However, especially when it comes to life sciences and medicine, we tend to be very sensitive as it affects our bodies.
Within the framework of the NANO-REGION project, funded by the Interreg V-A Italy-Slovenia Programme 2014-2020, a Proof-of-Concept activity took place focusing on materials for dental prosthesis with very high requirements in terms of functionality, usability, performance and above all safety of use. Polident is a company that produces acrylic teeth, materials suitable for making artificial crowns and temporary bridges, filling materials, dental plasters and the like.
In particular, the company produces multilayer acrylic teeth in different shades, shapes and compositions. The tooth production technology itself is developed and well established, but very complex. There are several factors that influence the quality and durability of the end result. Factors such as process parameters, mould design, imitation of natural tooth morphology, material composition and structure. The production itself is complex and therefore demanding, and expectations on the aesthetic side of the final product are very high, which is why there is often a large amount of material that is discarded during the process. The company's aim is to reduce the amount of waste products in the production process.
The aim of the second experiment within the framework of the cooperation with the NANO - REGION network was to study the defects in the process that cause a conspicuous amount of waste, to understand the reasons for them and to deal with them. The defects include various mechanical irregularities (micro-cracks, micro-porosity), visual defects, and lamination between layers.
The material was studied under an optical microscope, which revealed that the visible defects are not only present on the surface, but are also embedded in the polymer matrix. In addition, the number of inclusions within the polymer is higher than visible when observing the sample, but only defects near the surface are visible to the naked eye. After a thorough polishing process, it is possible to expose the defects, i.e. bring them close to the surface, and study them with Scanning Electron Microscopy (SEM). SEM back-scattered electron imaging has proven to be the most effective in analysing morphology. EDX (energy dispersive X-ray analysis) was conducted to try to understand the elements in the defects. This allowed defective components to be identified when they are above the EDX detection limit.
Operation co-funded by the European Regional Development Fund
