Abstract:
Objective To compare different effects of cells on titanium surfaces with different micro/nano structures, and to evaluate different functions of micro- and nano-features, respectively.
Methods All the titanium disc samples were divided into four groups and accepted the following treatments: (1) sandblasted only (S) ; (2) sandblasted followed by acid-etching (SLA) ; (3) sandblasted followed by alkali-heat (SAH) ; (4) sandblasted followed by anodizing (SAN) . The surface topography, elemental component and roughness of samples were examined. Surface biocompatibility and osteogenic capability were evaluated by cell counting kit (CCK-8) and alkaline phosphate activity (ALP) in vitro. The level of significance was determined by a one-way ANOVA followed by a least significant difference (LSD) t-test for a multiple comparison procedure.
Results Surface of group S were showed only microtopography of pits, while the other three groups exhibited primary micro-structure modified by secondary nano-features of ditches (SLA) , nano-porous network layers (SAH) and nanotubes (SAN) , respectively. There was no significant difference of cell adhesion and proliferation in the 1st and 3rd day. Group SAH and SAN (1.546 and 1.528) enhanced cell proliferation significantly than Group S (1.31) in the 5th day (F = 3.229, P = 0.042) , in the 7th day, Group SAH and SAN (2.646 and 2.57) also significantly enhanced cell proliferation than Group S (2.24) (F = 3.51, P = 0.035) and induced affluent and stretched cell pseudopods. Moreover, pseudopods on the surface of group SAH grow into the network and wrap around the net to link to each other. In comparison, group SAH (77.656) significantly enhanced ALP activity in the 7th day than Group S, SLA and SAN (53.132, 51.052 and 62.207, respectively) (F = 29.734, P<0.001) , though the ALP activity of group SAN depressed in the early stage but enhanced significantly than Group S and SLA (82.885 and 73.303) in the 14th day (F = 46.052, P<0.001) .
Conclusions Microstructures decided the roughness while nanostructures, especially nano-porous functioned in enhancing cell proliferation and differentiation. The forms of nano-porous induced cell pseudopods stretch, for which nano-porous network allowed cells to grow into and form extensive interlocking.
Key words:
Surface modification,
Micro/Nano structure,
Titanium,
Nano networks,
Nanotubes
Jiayun Xu, Feilong Deng, Xiumei Zhuang, Jianglin Ou-Yang, Yun Liu, Jing Wang, Xiachen Li. The influence of different hybrid micro/nano hierarchical titanium topographies on osteoblast biological functions[J]. Chinese Journal of Stomatological Research(Electronic Edition), 2015, 09(06): 461-469.