Non-aqueous dental adhesive comprising a mixture containing (i) one or more polymerizable monomers optionally containing an acidic group, (ii) a polymerization initiator, and (iii) a thermal polymerization inhibitor of the following formula (I)whereinR′1 represents a hydrogen atom, or a saturated hydrocarbon group having 1 to 18 carbon atoms. R′2, which may be the same or different if more than one R′2 is present, independently represent a saturated hydrocarbon group having 1 to 18 carbon atoms, and c represents an integer of from 1 to 4, and (iv) optionally an organic solvent.
