Abstract: Bone-like apatite formation on the surface of calcium phosphate ceramics has been believed to be the necessary step that new bone grows on the ceramics and
to be relative to the osteoinductivity of the material. The research of the factors effecting bone-like apatite formation is a great help to understanding the mechanism
of osteoinduction. This study was a comparative study of in vitro formation of bone-like apatite on the surface of dense calcium phosphate ceramics with SBF
flowing at different speeds. The results showed that the rough surface was beneficial to the formation of bone-like apatite and the apatite formed faster in 1.5 SBF
than in SBF. Rough surface, namely, larger surface area, increased the dissolution of Ca²⁺, HPO₄^2- and higher concentration of Ca²⁺ and HPO₄^2- ions of SBF
was advantageous to the accumulation of Ca²⁺, HPO4^2-, PO₄^3- near the ceramic surface. Local supersaturating concentration of Ca²⁺, HPO₄^2-, PO₄^3-
near sample surface was critical for nucleation of apatite on the surface of sample.

Key words: dense calcium phosphate ceramics, dynamic SBF, bone-like apatite