Abstract: The invention relates to a polymerisable composition comprising (i) 0 to 90% by weight of at least one inorganic filler component, (ii) 5 to 99.98% by weight of at least one urethane (alkyl) acrylate of the idealised formula I, (iii) 0.01 to 25% by weight of at least one di-, tri-, tetra- or multi-functional monomer, not being a urethane (alkyl) acrylate, (iv) 0.01 to 10% by weight of at least one initiator, of an initiator system as well as optionally of at least one stabiliser and optionally of at least one pigment, the total composition of the composition amounting to 100% by weight, as well as a polymerised composition having improved fracture toughness.

Abstract: The invention relates to a polymerisable dental composite material comprising (i) 40 to 90% by weight of an inorganic filler component comprising at least one dental glass, as well as optionally at least one an amorphous metal oxide, (ii) 10 to 60% by weight of at least one urethane (alkyl) acrylate of the idealised formula I, (iii) 0.01 to 15% by weight of at least one di-, tri-, tetra- or multi-functional monomer not being a urethane (alkyl) acrylate, (iv) 0.01 to 10% by weight of at least one initiator, of an initiator system, as well as optionally of at least one stabiliser, and optionally of at least one pigment, the total composition of the composite material amounting to 100% by weight, as well as to a polymerised composite material for producing direct dental restorations or indirect dental restorations.

Abstract: Torsional damper (34), with an input element (E), an output element (A), an elastic element (16), and a friction device (36). The input element (E) and the output element (A) are rotatable to a limited extent with respect to one another against a restoring force of the elastic element (16). The friction device (36) has a friction disk (24), a holding element (28) and a preloading element (26), wherein the holding element (28) is connected to the friction disk (24) for conjoint rotation therewith. The holding element (28) is connected to the output element (A) for conjoint rotation therewith. The holding element (28) is arranged axially between the friction disk (24) and the preloading element (26). A clutch disk having a torsional damper as described above is also disclosed.