Structural Characterization of Strontium Silicate Glasses and Glass Ceramics Applied as Glass Ionomer Cements (GICs)

Abstract

Oxide glasses and glass ceramics in the xSrO-(45-x) SiO2-24.5CaO-24.5Na2O-6 P2O5, (x changes from 0 to 15 mol %) have been prepared and studied by several spectroscopic techniques. The structure of all as obtained compositions was confirmed to be amorphous in nature. The as prepared glasses were treated thermally at a specific temperature to activate the nucleation processes, which is suitable for the material to be used as scaffolds and implants. The glass ionomer cements (GICs) are prepared from two parts: powder of the crystallized glasses mixed with an aqueous poly (acrylic) acid solution. The state of GIC was checked up by both FTIR and NMR spectroscopy. The cement of strontium and calcium carboxyl groups are confirmed to be formed. The results based on NMR study suggested that the glass containing a significant amount of non-bridging oxygens NBOs can dissolve quickly in specific solutions and vice versa. GIC of chemical shift in the region of shielded silicate units (contains three bridging bonds) are confirmed to be formed. The shielded silicate units in the well-formed GIC prevent the material from corrosion and dissolutions in water that was checked up by durability measurement (Dr). Consequently, the as-obtained GIC is recommended to be applied as restorative and /or implants and scaffolds.