Evaluating the Prospects of Ti-Base Lattice Infiltrated with Biodegradable Zn-2%Fe Alloy as a Structural Material for Osseointegrated Implants-In Vitro Study

Materials (Basel). 2021 Aug 19;14(16):4682. doi: 10.3390/ma14164682.

Abstract

The term "osseointegrated implants" mainly relates to structural systems that contain open spaces, which enable osteoblasts and connecting tissue to migrate during natural bone growth. Consequently, the coherency and bonding strength between the implant and natural bone can be significantly increased, for example in operations related to dental and orthopedic applications. The present study aims to evaluate the prospects of a Ti-6Al-4V lattice, produced by selective laser melting (SLM) and infiltrated with biodegradable Zn2%Fe alloy, as an OI-TiZn system implant in in vitro conditions. This combined material structure is designated by this study as an osseointegrated implant (OI-TiZn) system. The microstructure of the tested alloys was examined both optically and using scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis. The mechanical properties were assessed in terms of compression strength, as is commonly acceptable in cases of lattice-based structures. The corrosion performance was evaluated by immersion tests and electrochemical analysis in terms of potentiodynamic polarization and electrochemical impedance spectroscopy (EIS), all in simulated physiological environments in the form of phosphate buffered saline (PBS) solution. The cytotoxicity was evaluated in terms of indirect cell viability. The results obtained demonstrate the adequate performance of the OI-TiZn system as a non-cytotoxic structural material that can maintain its mechanical integrity under compression, while presenting acceptable corrosion rate degradation.

Keywords: SLM; Ti–6Al–4V; Zn–Fe; additive manufacturing; biodegradable Zinc; dental; lattice; orthopedic; osseointegration.