In Vitro Evaluation on Bone-Bonding of Chemically Modified Titanium

Chemical treatment of commercially pure titanium (cpTi), involving soaking in a 30 wt% H2O2 solution containing 3 M TaCl5 at 80 C for 1 h followed by heating at 400 C for 1 h in air, provides in-vitro bioactivity. A titania gel layer formed on the surface plays an essential role. The effects of surface roughness and gel thickness on in-vitro bioactivity of cpTi was evaluated in Kokubo solution (SBF). Surface roughness was introduced by mechanical abrasion of cpTi, and the resultant gel layer thickness was controlled by changing the chemical treatment temperature (60 or 80 C). The bond strength between the substrate/titania and titania/apatite layers was determined by shear strength tests. In-vitro evaluation suggested that the interfacial bond strength between the bone and Ti implants could be enhanced by forming a thinner titania layer on a rougher cpTi surface. 4 refs.