The present disclosure relates to an aqueous dental glass ionomer composition comprising a reactive particulate glass, a water-soluble, polymerizable polymer which is reactive with the particulate glass in a cement reaction, a hydrolysis-stable, water-soluble monomer having a single polymerizable double bond and optionally a carboxylic acid group or hydroxyl group; and a polymerization initiator system, wherein the polymerizable polymer is obtainable by a process comprising a step of polymerizing a mixture comprising a first polymerizable monomer comprising at least one optionally protected carboxylic acid group and a first polymerizable organic moiety, and optionally a second copolymerizable monomer comprising one or more optionally protected primary and/or secondary hydroxyl and/or amino group(s) and a second polymerizable organic moiety, for obtaining an water-soluble polymer; a step of coupling to the water-soluble polymer a compound having a olymerizable moiety and a functional group reactive with an optionally protected carboxylic acid group of repeating units derived from the first polymerizable monomer or an optionally protected hydroxyl and/or amino group of repeating units derived from the second copolymerizable monomer in the water-soluble polymer obtained in step a), wherein the optionally protected carboxylic acid group and the optionally protected hydroxyl and/or amine group are deprotected, so that polymerizable pendant groups are linked to the backbone by ester groups, urethane groups and/or amide groups, and, optionally, a step of deprotecting the protected carboxylic acid group for obtaining a polymerizable polymer.