Surface microtopography design and manufacturing through topography descriptors: an application to prosthetic implant surfaces

In this work, the proposed methodology is applied to the design of the microtopography of the coated surface of a prosthetic implant. Topography descriptors are identified which are suitable to describe microtopographic properties related to a specific functional property: the bone-implant interfacial shear strength. Such topography descriptors are evaluated over real specimens, obtained by Vacuum Plasma Spray deposition of porous titanium or fluorinated hydroxyapatite over a titanium alloy substrate, in order to assess their relationship with functional performance. Then, a dedicated procedural model, embedding Vacuum Plasma Spray simulation algorithms, is developed to generate virtual microtopographies with the intent of understanding the relationships between topography descriptors and manufacturing process parameters, for process planning purposes. The developed models and obtained results are discussed and their suitability as tools for surface topography design and manufacturing is assessed.