One of the important properties of the bioactive implants is the apatite formation on them surface in simulated body fluid. This phase in terms of the composition and structure is similar to the mineral phase of bone. The aim of this study was to investigate the effect of different bioactive ceramic types including bioactive glass36S, hydroxyapatite (HA), fluorapatite, magnesium -substituted fluorapatite di calcium silicate (?-Ca 2 SiO 4 ), diopside (CaMgSi 2 O 6 ), bredigite (Ca 7 MgSi 4 O 16 ), merwinite (Ca 3 MgSi 2 O 8 ) and forsterite (Mg 2 SiO 4 ) on the morphology of apatite formed in vitro. The nanopowders of these bioceramics were synthesized by sol-gel method. In order to identify and characterization, techniques were used of x-ray diffraction (XRD), scanning electron microscopy(SEM), field emission scanning electron microscopy(FESEM), energy dispersive x-ray spectroscopy(EDS) and fourier transform -infrared spectroscopy(FTIR) for the prepared powders. The results confirmed that the prepared powders were pure and grain size lower than 50 nm. In vitro bioactivity evaluation was performed by soaking the prepared samples in SBF for period of times. In order to characterize the samples, identify and study the morphology of formed bone like-apatite, and determine the concentration amount of released ions in the SBF, SEM, FTIR, inductively-coupled plasma optical emission spectroscopy (ICP-OES) and EDS were utilized. Result showed that the morphology of the formed apatite depends on the type of bioceramics and different amount of ion release from bioceramics. The ceramic with the highest Mg content showed the lowest ability for apatite formation. In the case of bioceramics containing SiO 2 , the bone-like apatite with increasing Si ions in SBF solution, the morphology of the apatite became more regular shaped. Key Words: Bioactivity, Bone-like apatite, Bioceramic, Simulated Body Fluid (SBF).
