The invention provides a dental root sealing composition curable in theabsence of a polymerization initiator and having a viscosity at 23°C oflessthan 100 Pa*s, which comprises:(i) an amino terminated prepolymer having a viscosity at 23°C of lessthan 100 Pa*s obtained by reacting(a) one mole of a compound of formula (I)(see formula I) and(b) at least n moles of one or more compounds either of formula (II)(see formula II)or of formula (II) in combination with one or more di- or polyamine compounds；(ii) a di- or polyfunctional acrylate compound or a di- or polyfunctionalmaleimide compound capable of undergoing polyaddition with the prepolymer (i)；(iii) 40 to 85 wt% of a filler for providing a minimum radioopacity of atleast 3 mm/mm Al；in the form of a two-component composition wherein a first component contains(i), asecond component contains (ii) and (iii) is in one or both of the first andsecondcomponents.
