Fabrication of P<inf>2</inf>O<inf>5</inf>-CaO-Na<inf>2</inf>O glasses doped with magnesium oxide for artificial bone applications

Abstract

Effects of MgO doping on properties of P2O5-CaO- Na2O glass system were investigated. The glass samples were prepared by conventional glass melting technique at 1000 °C for 1 h. Thermal parameter of each glass sample were studied by differential thermal analysis (DTA). The glass samples were annealed at crystallization temperature to form glass ceramics. The glass ceramics were investigated in terms of phase formations by XRD, microstructure by SEM and in vitro bioactivity. The phases formed in all glass ceramics are calcium phosphate (Ca2P2O7file no. 09-0346), sodium phosphate (NaPO3file no. 11-0650) and sodium calcium phosphate (Na1.8Ca1.1P6O17file no. 47-0863) as detected by XRD. The 5-10 mol% MgO glass ceramics having well separated two crystallization peaks (Tx1and Tx2) within the temperature range of 557-590 °C contained additional sodium magnesium phosphate (NaMg(PO3)3file no. 72-2341). Large porosity was found in all glass ceramics due to free volume and void formation during the crystallized phase. The in vitro study revealed that all glass ceramic samples exhibited apatite cell growth at the surface after immersed in simulated body fluid (SBF) for 7 days. The results suggested that these glass ceramics were appropriate for biomedical application. © 2012 Elsevier Ltd and Techna Group S.r.l.