A kit for preparing a paste-like bone cement, comprising a paste A and a paste B, wherein paste A contains (a1) at least one monomer for radical polymerization, (a2) at least one polymer that is soluble in (a1); and (a3)at least one polymerization initiator; and paste B contains (b1) at least one monomer for radical polymerization; (b2) at least one polymer that is soluble in (b1); and (b3) at least one polymerization accelerator; wherein at least one of the pastes A and B contains as component (a4) and/or (b4) at least one filling agent that is poorly soluble or insoluble in (a1) and/or (b1), respectively, and wherein the filling agent is a particulate inorganic filling agent possessing a BET surface of at least 40 m2/g.