The invention relates to a curable composition comprising a resin matrix, the resin matrix comprising cationically curable components (A) and radiation curable components (B), a curing system, the curing system comprising a starter (A-S) suitable for curing the cationically curable components (A) and a photo-initiator (B-I), the curable composition being provided as a Base Part and Catalyst Part being separated before use, wherein the Base Part comprises components (A) and (B) and wherein the Catalyst Part comprises components (A-S) and (B-I). The composition can be used for taking a dental impression including the subgingival parts.