[Compression of amalgam specimens under various loads]

To test the behavior of amalgam fillings under masticatory load, 72 cylindrical amalgam specimens (d=5mm, h=10mm) were exposed to alternating loads changing from zero pressure to a pressure of 10 N/mm2. The tests were made in a conventional and four silver amalgams rich in copper, in water baths of 30 degrees, 37 degrees, 50 degrees, and 60 degrees C. Compression of the specimens results, which increases proportionally to the cube root of the number of alternating loads and with rising temperature. The compression lies between 0.3 per cent to 5 per cent of the original length after 10,000 alternating loads, depending on amalgam and temperature. Compressive strength increased under alternating load.