Effects of different acid etching protocols on the enhanced osteogenic potential of titanium surfaces: An <i>in vitro</i> study

Sandblasted with large grits and acid-etched (SLA) surface topography has been a common method of implant surface modification to promote bone-implant integration in titanium-based dental implant manufacturing. However, the acid etching protocols used are various. The aim of this investigation was to validate the effect of different acid-etched treatments of sandblasted titanium surfaces on enhancing osteogenic potential. Five different titanium surface groups were prepared and tested including: i) smooth (Control), ii) sandblasted (SL), iii) sandblasted and acid-etched with H₂SO₄/HCl mixed solution (SLA/SOCl), iv) sandblasted and acid-etched with H₂SO₄ solution (SLA/SO), and v) sandblasted and acid-etched with HF solution (SLA/HF). The surface characterization, protein adsorption, and cell behavior were examined to determine the osteogenic potential. Compared with the control group, other surface treated groups showed rougher surface, better wettability, more protein absorption, and cell viability, especially in the SLA/SOCl surface group. The results indicated that SLA surfaces prepared with H₂SO₄/HCl mixed acid solution provided significant potential to promote osteogenesis.