Abstract: Disclosed herein is a soft, putty-like material for lining a denture base, comprising 100 parts by weight of a monomeric compound represented by the formula (I): ##STR1## wherein R.sup.1 represents a hydrogen atom or a methyl group and R.sup.2 represents a residual group formed by removing a hydroxyl group from a fluorine-containing telomer having a molecular weight of less than 1500, 3 to 30 parts by weight of a fluorine-containing copolymer, 3 to 30 parts by weight of a C.sub.1 to C.sub.12 -alkyl acrylate or methacrylate and 0.1 to 3.0 parts by weight of a polymerization-initiator.