Influence of ceramic disk material, surface hemispheres, and SBF volume on in vitro mineralization

Calcium phosphate ceramics are the main mineral constituents of bone and teeth and have therefore been extensively investigated for bone regenerative applications. In the current study, the effect of disk material, surface geometry, and SBF volume on mineralization capacity was investigated. Hemispherical concavities were created on the surfaces of disks made of different materials (i.e., hydroxyapatite (HA), β-tricalcium phosphate (β-TCP), biphasic calcium phosphate (BCP) and titanium (Ti)) which were sintered at 1200 °C. Mineralization of CaP was assessed on disk surfaces after immersion of the samples in different volumes of simulated body fluid (SBF) up to 14 days by means of calcium assay and scanning electron microscopy (SEM). This study showed that different SBF volumes have different effects on mineralization, with an optimum material/liquid ratio of 5 mL of SBF per cm(2) . Additionally, at this volume, apparent differences based on disk material became obvious. Evidently, surface hemispherical concavities acted as initiator areas for nucleation and crystal growth.