Highly flowable prepolymer composition of high radiopacity allowing for high depth photopolymerization

A highly flowable, crosslinkable medical or dental composition, said highly flowable composition comprising a crosslinkable compound, a polymerization initiator and a heterogeneous, solid radiopacifier wherein;

• i. it has a radiopacity of at least 3 mmAl/mm according to ISO 13116-2014,
• ii. it remains a stable dispersion for 30 days at about 37° C., stability referring to less than 1% of the heterogenous solid precipitating,
• iii. it has a flowability >40 mm according to ISO 6876-2012 measured at room temperature (22° C.), and
• iv. the heterogeneous radiopacifier has an average particle size between 1 and 500 nm measured by transmission electron microscopy according to ISO 21363-2020, and
• wherein the composition further comprises water as a solvent, and
• wherein the composition contains 5-70% in weight of the crosslinkable material, 5-60% in weight of the heterogeneous radiopacifier, 5-60% in weight of the suitable solvent, and 0.001-10% in weight of the polymerization initiator.