Bioactivities of a Ti surface ablated with a femtosecond laser through SBF.

Micro-patterns with deposited calcium/phosphorus (Ca/P) elements on a pure titanium (Ti) surface were synthesized in 2.5 x simulated body fluid (SBF) by femtosecond laser ablation, and their bioactivities were evaluated by co-culture with osteoblasts. Scanning electron microscope observation showed that a three-order roughness micro-pattern, which was composed of grooves, islands, holes and sub-micro-particles, was obtained, and the size of holes and islands was increased from 0.5 µm and 2 µm to 5 µm and 6 µm, respectively, gradually with the increase of laser fluence from 3.3 J cm(-2) to 12.5 J cm(-2). Irradiation of femtosecond lasers promoted the deposition of Ca/P on the surface of a Ti plate. The osteoblasts grew faster and extended more slender filopodia on the femtosecond laser-ablated surface than on a sand blast followed by an acid surface, which demonstrated that the micro-patterns with deposited Ca/P on the surface were favorable for osteoblasts' growth.