1999 Volume 107 Issue 1250 Pages 935-943
Composite cements consisting of different pairs of inorganic filler-resin were prepared by selecting CaO-SiO2-P2O5-CaF2 glass, glass-ceramic A-W and silica glass powders as inorganic fillers, and combining each of them with bisphenol-a-glycidyl methacrylate/triethylene glycol dimethacrylate (Bis-GMA/TEGDMA) resin. The mechanical behavior of each of the composite resin cements was investigated by examining their fracture strength in a simulated body fluid (SBF) as a function of both the soaking time and the stressing rate. It was found that, among the composite cements studied, the CaO-SiO2-P2O5-CaF2 glass-filled composite cement showed a rapid strength degradation with increasing the soaking time in SBF and the highest sensitivity to time-dependent fatigue in SBF. On the other hand, the strengths of the resin cements filled with glass-ceramic A-W and silica glass particles did not vary with soaking time up to 336d in SBF. Thus, glass-ceramic A-W and silica glass can strengthen the resin cement without increasing the sensitivity to time-dependent fatigue in SBF. The glass-ceramic A-W can be used as a reliable inorganic filler for the composite cements with the Bis-GMA/TEGDMA resin, because of its bioactivity and good chemical stability.
