Mechanical behavior of bioactive inorganic filler-resin composite cements in a simulated body fluid: Effect of filler material

Composite cements consisting of different pairs of inorganic filler-resin w ere prepared by selecting CaO-SiO2-P2O5-CaF2 glass, glass-ceramic A-W and s ilica glass powders as inorganic fillers, and combining each of them with b isphenol-alpha-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 simulat ed 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 degradatio n with increasing the soaking time in SBF and the highest sensitivity to ti me-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 va ry with soaking time up to 336 d in SBF, Thus, glass-ceramic A-W and silica glass can strengthen the resin cement without increasing the sensitivity t o time-dependent fatigue in SBF. The glass-ceramic A-W can be used as a rel iable inorganic filler for the composite cements with the Bis-GMA/TEGDMA re sin, because of its bioactivity and good chemical stability.