(Meth)-acrylic acid esters of the formula ##STR1## in which R.sup.1 and R.sup.2 are each independently hydrogen, chlorine, fluorine or a C.sub.1 - to C.sub.4 -alkyl radical andR.sup.3 and R.sup.4 are identical or different and represent the group ##STR2## wherein Y is a divalent bridge member from the group ##STR3## and Z is a straight-chain or branched hydrocarbon chain which has 2 to 10 carbon atoms, can optionally contain oxygen bridges and is optionally substituted by 1 to 4 acrylate or methacrylate radicals,whereinR.sup.5 represents hydrogen or methyl andR.sup.6 represents hydrogen, C.sub.1 -C.sub.6 - alkyl or phenyl,which are useful as dental materials.