Wechsellastverhalten von zwei Kompositen unter Simulation physiologischer Bedingungen

The fatigue behaviour of a conventional and a microfilled composite filling material was investigated simulating physiological loading and environmental conditions. Using three different standard test-arrangements (3-point-bending, axial and diametral compression) the specimens were cycled at various stress levels until fracture according to the Wöhler-procedure, as well under laboratory conditions as in Ringer's solution at 37 degree C. The shape of the loading function represented an idealized chewing curve. A strong decrease in strength with increasing cycle numbers is observed for the two materials. Compared with the quasistatic strength values, after 1 million cycles the fatigue strength is reduced by 50 to 65% depending on material and conditions: The strongest differences are caused by the materials, whereas the influence of the testing procedure and the environment is only small or even negligible.