Surface characteristics and biocompatibility of sandblasted and acid-etched titanium surface modified by ultraviolet irradiation: an in vitro study.

Sandblasting with large grit and acid-etching (SLA) treatment is considered to be a reliable modification to achieve excellent titanium surface. However, contamination of hydrocarbons would make SLA surface hydrophobic and influence its bioactivity. Thus, appropriate methods of preservation or further treatments could be used for improvement. In present study, preservation in deionized water (dH(2)O) and ultraviolet (UV) irradiation were, respectively, applied to achieve modSLA and UV-SLA surfaces. Surface characteristics were assessed by scanning electron microscopy, optical profilometer and x-ray photoelectron spectroscopy as well as wettability by optical contact angle analyzer. Additionally, biocompatibility was evaluated by the response to osteoblast-like MG63 cells. Prevented from further contamination, modSLA surface with fewer hydrocarbons (25.31%) remained hydrophilic and showed better affinity to mineralization of MG63 cells than hydrophobic polluted SLA surface (p < 0.01). Furthermore, with the lowest content of hydrocarbons (14.26%) and super-hydrophilicity, UV-SLA surface, which had the hydrocarbons effectively decomposed by photocatalysis and meanwhile acquired abundant hydroxyl groups, had most greatly promoted the attachment, proliferation, differentiation, and mineralization of MG63 cells (p < 0.05). Therefore, hydrocarbons were found to be an important influencing factor to compatibility of biomaterials. In addition, UV irradiation was recognized as a trustworthy method for surface cleaning without change of topography and roughness and could ever lead to greater biocompatibility of sandblasted and acid-etched titanium surface.