A hardenable multi-part acrylic composition comprises a solid first part and a storage stable liquid second part and optionally, further solid and/or liquid parts, the parts being operable to form a cement which hardens to a solid mass upon mixing. The composition further comprises an acrylic monomer component in the second part, an initiator component, a first sub-population of acrylic polymer particles in the first and/or further parts, a second sub-population of acrylic polymer particles in the first and/or further parts and optionally, one or more further sub-population(s) of acrylic polymer particles, and a radiopacifying filler. The initiator component amount is effective to polymerize the acrylic monomer component upon mixing. At least some of the radiopacifying filler is encapsulated within and/or adsorbed on the first sub-population of acrylic polymer particles and the second sub-population of acrylic polymer particles has a lower average particle size than the first.
