Reactive resin component comprising at least one radically curable unsaturated compound and at least one filler made of oxides of silicon, which filler is modified with a silane that has reactive groups capable of participating in the polymerization with the radically curable unsaturated compound, and optionally comprising other different inorganic additives, the proportion of all inorganic solids in the reactive resin component being at least 60 wt.% and that the proportion of the at least one filler made of oxides of silicon, which filler is modified with a silane that has reactive groups capable of participating in the polymerization with the radically curable unsaturated compound and which has a grain diameter of 4 μm or smaller, is 0.5 to 60 wt.%, based on the reactive resin component, characterized in that the radically curable unsaturated compound comprises (i) 35 wt.% or more, based on the reactive resin component, of a compound having at least two carbon-carbon double bonds, the weight-average molecular weight of which per carbon-carbon double bond is greater than 230 g/mol and the viscosity of which is greater than 2500 mPa·s (measured in accordance with DIN 53019 at 25°C); or (ii) 30 wt.% or more, based on the reactive resin component, of a compound having at least two carbon-carbon double bonds, the weight-average molecular weight of which per carbon-carbon double bond is greater than 230 g/mol and the viscosity of which is greater than 2500 mPa·s (measured in accordance with DIN 53019 at 25°C), and 10 wt.% or more, based on the reactive resin component, of a compound having at least two carbon-carbon double bonds, the weight-average molecular weight of which per carbon-carbon double bond is greater than 125 g/mol and the viscosity of which is less than 2500 mPa·s (measured in accordance with DIN 53019 at 25°C); or (iii) 57 wt.% or more, based on the reactive resin component, of a compound having at least two carbon-carbon double bonds, the weight-average molecular weight of which per carbon-carbon double bond is greater than 225 g/mol and the viscosity of which is less than 2500 mPa·s (measured in accordance with DIN 53019 at 25°C); or (iv) 50 wt.% or more, based on the reactive resin component, of a compound having at least two carbon-carbon double bonds, the weight-average molecular weight of which per carbon-carbon double bond is greater than 225 g/mol and the viscosity of which is less than 2500 mPa·s (measured in accordance with DIN 53019 at 25°C), and 10 wt.% or more, based on the reactive resin component, of a compound having at least two carbon-carbon double bonds, the weight-average molecular weight of which per carbon-carbon double bond is greater than 125 g/mol and the viscosity of which is less than 2500 mPa·s (measured in accordance with DIN 53019 at 25°C). (i) 35 wt.% or more, based on the reactive resin component, of a compound having at least two carbon-carbon double bonds, the weight-average molecular weight of which per carbon-carbon double bond is greater than 230 g/mol and the viscosity of which is greater than 2500 mPa·s (measured in accordance with DIN 53019 at 25°C); or (ii) 30 wt.% or more, based on the reactive resin component, of a compound having at least two carbon-carbon double bonds, the weight-average molecular weight of which per carbon-carbon double bond is greater than 230 g/mol and the viscosity of which is greater than 2500 mPa·s (measured in accordance with DIN 53019 at 25°C), and 10 wt.% or more, based on the reactive resin component, of a compound having at least two carbon-carbon double bonds, the weight-average molecular weight of which per carbon-carbon double bond is greater than 125 g/mol and the viscosity of which is less than 2500 mPa·s (measured in accordance with DIN 53019 at 25°C); or (iii) 57 wt.% or more, based on the reactive resin component, of a compound having at least two carbon-carbon double bonds, the weight-average molecular weight of which per carbon-carbon double bond is greater than 225 g/mol and the viscosity of which is less than 2500 mPa·s (measured in accordance with DIN 53019 at 25°C); or (iv) 50 wt.% or more, based on the reactive resin component, of a compound having at least two carbon-carbon double bonds, the weight-average molecular weight of which per carbon-carbon double bond is greater than 225 g/mol and the viscosity of which is less than 2500 mPa·s (measured in accordance with DIN 53019 at 25°C), and 10 wt.% or more, based on the reactive resin component, of a compound having at least two carbon-carbon double bonds, the weight-average molecular weight of which per carbon-carbon double bond is greater than 125 g/mol and the viscosity of which is less than 2500 mPa·s (measured in accordance with DIN 53019 at 25°C).