Cell proliferating responses to magnesium coated β-TCP surface

Abstract

Bioactive calcium phosphate ceramics, such as hydroxyapatite (HA) and β-tricalcium phosphate (β-TCP), have been considered for use as synthetic bone graft substitutes in regenerative surgeries. However, the rate of bioresorption of β-TCP is unpredictable. In order to resolve the drawbacks of β-TCP, coatings of bioactive materials on the apatite graft base materials were introduced. Magnesium (Mg) plays a crucial role in cell proliferation and function. Cells are unable to proliferate in the absence of extracellular Mg because of the resultant reduction in DNA, RNA and protein synthesis. This study was performed to evaluate early osteoblastic cell responses to Mg coated β-TCP surfaces. The bioactive surfaces on β-TCP base were developed by radio frequency (RF) magnetron coating method. Thin Mg coating on β-TCP substrates was performed. Surface characteristics were evaluated by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX). The bioactivity of coated surfaces was also evaluated by SEM and cell proliferation. The disks were divided into 2 groups: control group (TCP) and test group (TCP-Mg). SEM and EDX analysis showed that Mg deposition on the β-TCP substrates were performed successfully. Under SEM, no significant difference in cell morphology was observed between the TCP and TCP-Mg groups. In the MTT assay, the TCP-Mg group had significantly better cellular responses with regard to proliferation at 5 days (p<0.05). Within certain limitations, the results of this study suggests that Mg coatings on β-TCP offers great potential as a graft material for hard tissue regeneration.