Effects of Oxide Ceramic Addition on Biocompatibility of Titanium

Titanium and its alloys are known for their excellent biocompatibility and mechanical performance and are used widely in load-bearing implant applications. However, titanium is bioinert, i.e., it does not help in bone-tissue interactions, thus not aiding in expedited patient healing. The inorganic phase of the bone contains macro-nutrients in trace elements such as Mg2+, Si4+, which play a vital role in bone formation and remodeling. The addition of ceramics such as magnesium oxide (MgO) and silicon dioxide (SiO2) in calcium phosphate coatings on titanium surfaces is widely popular. Magnesium is known to promote osteogenesis and silicon for angiogenesis. This study introduced 1 wt.% of MgO and SiO2 in commercially pure titanium (CpTi) via additive manufacturing. Also, surface modification of titanium via TiO2 nanotubes (TNTs) has proven to enhance osseointegration. We have tested the effects of MgO- and SiO2 -based CpTi compositions with TNT on osteoblast cells to evaluate the synergistic effect of ceramic addition and TNT on biocompatibility. It was observed that CpTi-TNT showed better osteoblast cellular proliferation and differentiation compared to CpTi-MgO-TNT and CpTi-SiO2-TNT compositions. Post cell culture, good cellular coverage was observed on CpTi-TNT surfaces, whereas delamination of TNTs on MgOand SiO2-TNT compositions was observed, indicating that TNTs were not stable on the ceramic-Ti surface.