When using zirconia with a density of 5.68 g cm -3 the oligomer fraction is about 50 % and for tungsten carbide reaches almost 100 % with a density of 15.8 g cm . The effect of density and the resulting mass on kinetic energy is proportional, suggesting a proportional increase in yield. This cannot be confirmed for the soluble fraction, but a clear increase can be seen. The reason for this