Phenomenological model of creep of dental amalgam

Earlier work revealed that creep of a particular dental amalgam can be described by the model F(t) = F0 exp (t/t0)m. Here F(t) is the creep compliance at time t, whereas F0, t0 and m are constants of the model. In the previous study only three alloys were used. It was the aim of this study to investigate the factor alloy more thoroughly. After specimen preparation, the nineteen different amalgams were aged at 37 degrees C for either one day or one week. Then creep was determined at a temperature of 22.5 degrees C and a compressive stress of 117 MN/m2. F0 turns out to depend upon both the ageing time as well as on the choice of the alloy. As expected, t0 shows up substantial differences between the respective amalgams, whereas the differences between the two ageing are absent or relatively small. The factor alloy significantly influences m. However, the ageing time exerts no significant influence upon m.