Sensitivity of novel silicate and borate-based glass structures on bioactivity and degradation behaviour.

Three novel glass compositions, identified as NCL2 (SiO-based), NCL4 (BO-based) and NCL7 (SiO-based), along with apatite-wollastonite (AW) were processed to form sintered dense pellets, and subsequently evaluated for their bioactive potential, resulting physico-chemical properties and degradation rate. Microstructural analysis showed the carbonated hydroxyapatite (HCA) precipitate morphology following SBF testing to be composition-dependent. AW and the NCL7 formulation exhibited greater HCA precursor formation than the NCL2 and NCL4-derived pellets. Moreover, the NCL4 borate-based samples showed the highest biodegradation rate; with silicate-derived structures displaying the lowest weight loss after SBF immersion. The results of this study suggested that glass composition has significant influence on apatite-forming ability and also degradation rate, indicating the possibility to customise the properties of this class of materials towards the bone repair and regeneration process.