Fabrication of Micro-grooved Patterns on Hydroxyapatite Ceramics and Observation of Earlier Response of Osteoblasts to the Patterns

Hydroxyapatite (HAP) ceramic with orderly micro-patterned surface were fabricated by transferring micro-groove patterns from an aluminum alloy template, which was carved by an ultrasound-driven microprobe. The surface morphologies, phase compositions, and water wettability of samples were respectively analyzed with scanning electron microscope (SEM), X-ray diffraction (XRD), and contact angle measurements. The groove widths of three-kind samples were about 20, 40 and 60 μm, in lined with the designed values. Water wettability of the grooved HAP surfaces was found to be significantly increased by decreasing groove-width. Furthermore, the influences of the grooved HAP surfaces on the behavior of osteoblasts (MC3T3-E1) were examined by measuring cell orientation and counting the cell number. The results showed that the cells were oriented along the groove direction, and the cell orientation angles decreased with a decrease in groove-width, whereas no significant difference in the number of osteoblasts was observed. In summary, the groove-width of micro-patterned HAP has a distinct effect on the directed growth of osteoblast cells.