Curable composition for dental retraction

A kit of parts comprising a Catalyst Part I and a Base Part II for providing a curable composition for dental retraction, the kit of parts comprising:

• the Catalyst Part I comprising:
• component A1:
• at least one polyorganosiloxane with at least two olefinically unsaturated groups, and
• a catalyst system comprising:
• an addition cure catalyst component C-A suitable to cure components A1 and A2, and
• a condensation cure catalyst component C-B suitable to cure component B;
• the Base Part II comprising:
• component A1:
• at least one polyorganosiloxane with at least two olefinically unsaturated groups
• component A2:
• at least one organohydrogenpolysiloxane,
• component B:
• at least one alkylsiloxane having at least one carbinol, silanol, or alkoxy moiety, wherein component B is present in an amount of at least 6 wt. % with respect to the weight of the curable composition,
• component D comprising filler(s) in a total amount of 10 to 50 wt % with respect to the weight of the curable composition, wherein the filler(s) are present in one or more of the Catalyst Part I and the Base Part II,
• wherein at least two different polyorganosiloxane with at least two olefinically unsaturated groups are present in the curable composition, the at least two polyorganosiloxane with at least two olefinically unsaturated groups differ in viscosity by a factor of at least 5, and
• wherein of the at least two different polyorganosiloxane with at least two olefinically unsaturated groups, a higher viscosity polyorganosiloxane is present in an amount relative to a lower viscosity polyorganosiloxane at a ratio of 0.9:1 to 3:1.