Influences of reinforcing agents on properties of biphasic calcium phosphate ceramics

Abstract

To improve biphasic calcium phosphate (BCP) ceramic strength, well known biocompatible and strong ceramics such as SiO₂, ZrO₂ and TiO₂ were added to BCP with hydroxyapatite/tricalcium phosphate ratios of 70:30 (BCP7030). SiO₂, ZrO₂ and TiO₂ powders with 2, 5 and 10 wt-% each were mixed with the BCP7030 powder. X-ray diffractometry and scanning electron microscopy (SEM) were used to determine the crystal structures and morphology of the sintered samples respectively. The physical properties and flexural strength of the samples were measured. Cell proliferation and differentiation of osteoblast-like Saos-2 cells cultured on BCP ceramics were determined by Alamar Blue assay and alkaline phosphatase expression respectively. Finally, SEM was performed to investigate the cell morphology on the surfaces of the specimens. The BCP7030 sample with 10 wt-%TiO₂ displayed an optimum bending strength of ∼61 MPa and showed the strongest enhancement of cell proliferation and differentiation among all tested reinforcing agents.

Keywords:

• Biphasic calcium phosphate
• Reinforcing agent
• Mechanical strength
• Biocompatibility
• Cell behaviour

This work was performed with support from the National Metal and Materials Technology Center, Ministry of Science and Technology of Thailand, under project no. P-1010331.