Biofilm Medium Leads to Apatite Formation on Bioactive Surfaces

Purpose When investigating apatite formation on biomaterial surfaces, simulated body fluid (SBF) is used as an in vitro solution, however, it does not provide an appropriate environment for the growth of bacterial biofilm. The aim of the present study was to compare the bioactivity in terms of apatite formation on two bioactive glass (BAG) composite surfaces using both SBF and bacterial-biofilm growing medium (BM). Methods Polymer composite substrates with different percentages of BAG–particles (50% and 75% by weight) were prepared. Plain resin substrates were used as a negative control. The substrates were immersed in SBF and BM for 3 days. The surface and, subsequently, the cross-sections of the substrates were examined with scanning electron microscopy (SEM) and x-ray energy dispersive spectroscopy (EDS). Results All the investigated BAG-composite surfaces showed apatite formation after immersion in SBF and BM liquid media. Conclusions: The use of BM is a promising method for studies involving simultaneous biofilm growth and apatite formation on bioactive surfaces.