Compatibility and Bone Bonding Efficiency of Gamma Irradiated Hench’s Bioglass

Abstract

This research focuses on investigating and characterizing the effects of gamma irradiation through successive doses on the bioactivity or bone bonding efficiency of samples from patented Hench’s bioglass upon immersion for extended times in stimulated body fluid (SBF). Combined analytical techniques including FT infrared, X-ray diffraction and scanning electron microscopic measurements were carried out to follow up and identify the changes of the studied properties with both gamma irradiation doses and time of immersion. FTIR spectra before and after both irradiation and immersion processes reveal vibrational bands due to main silicate groups and sharing of some mixed phosphate units in mid wavenumbers. Such collective studies show mainly the growth of the vibrational bands due to water, OH or related groups upon irradiation while the vibrational modes due to the main network forming groups remain unaffected by irradiation. The X-ray diffraction data indicate that gamma irradiation with 10 Mrad causes no changes in the amorphicity of the Hench’s bioglass as before irradiation while diffraction patterns of immersed samples reveal distinct peaks after 4 weeks of immersion. The gamma irradiated sample with 10 Mrad, shows only a peak after 2 weeks and more different peaks after 4 weeks of immersion. SEM micrographs are distinct revealing the appearance and growth of nodular shaped micro-crystallites with prolonged times of immersion confirming the formation of hydroxyapatite.