Characterization of biomaterials with reference to biocompatibility dedicated for patient-specific finger implants

Purpose: The research was focused on determining basic mechanical properties, surface, and phase structure taking into consideration basic cytotoxicity analysis towards human cells. Methods: Biological tests were performed on human C-12302 fibroblasts cells using 3D-printed Ti6Al4V alloy (Ti64), produced by laser-based powder bed fusion (LB-PBF) and Alumina Toughened Zirconia 20 (ATZ20), produced by lithography-based ceramic manufacturing (LCM). Surface modifications included electropolishing and hydroxyapatite or hydroxyapatite/zinc coating. Structure analysis was carried out using a variety of techniques such as X-Ray diffraction, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and confocal laser scanning microscopy (CLSM), followed by mechanical properties evaluation using nanoindentation testing. Results: Samples subjected to surface modifications showed diversity among surface and phase structure and mechanical properties. However, the cytotoxicity towards tested cells was not significantly higher than the control. Though, a trend was noted among the materials analysed, indicating that HAp/Zn coating on Ti64 and ATZ20 resulted in the best biological performance increasing cell survivability by more than 10%. Conclusions: Hydroxyapatite coating on Ti64 and ATZ20 resulted in the best biological properties. Tested materials are suitable for in vivo toxicity testin.