Polymerizable dental composition based on condensed silanes

A polymerizable dental composition comprising:

• (A) polysiloxanes, wherein the polysiloxanes comprise i) a mixture of the condensates of silanes (a1), (a2) and (a3), ii) a cocondensate of a mixture of silanes (a1), (a2) and (a3), iii) a mixture of at least two of the cocondensates (a1)/(a2), (a1)/(a3) and (a2)/(a3), iv) a mixture of the condensate of one of the three silanes (a1), (a2) or (a3) with the cocondesnate of the other two silanes, or v) combinations thereof,
• wherein silane (a1) has the formula (R1O)aR2bSi[—A(—Y{—B[—PG]f}e)d]c, wherein
• Y=—(X)x—C(═O)NH—, —NHC(═O)—(X)x— and —(X)xC(═O)N(—C(═O)NH—)—, —C(═O)NHC(═O)NH—, —NHC(═O)NHC(═O)—, wherein the bond arranged on the left in each formula is closer to the structural element A and the bond arranged to the right is closer to the structural element B,
• PG=polymerizable group,
• A=an organic linking group, connecting Si with Y and comprising 1 to 20 C-atoms,
• B an organic linking group, connecting Y with PG and comprising 1 to 20 C-atoms,
• X=O, S, or NH,
• R1=H or C1- to C4-alkyl,
• R2=C1- to C4-alkyl,
• a=2 or 3,
• b=0 or 1,
• c=1 or 2,
• d=1 to 3,
• e=1 or 2,
• f=1 to 5,
• a+b+c=4, and
• x=0 or 1,
• and wherein silane (a2) has the formula (R1O)aR2bSi[—A′(—PG)f]c], wherein
• PG=polymerizable group,
• A′=an organic linking group, connecting Si with PG, and comprising 1 to 20 C-atoms, wherein A′ is not —C(═O)NH—, —NHC(═O)—, —OC(═O)NH—, —NHC(═O)O—, —SC(═O)NH—, —NHC(═O)S—, —NHC(═O)NH—, —OC(═O)N(—C(═O)NH—)—, —SC(═O)N(—C(═O)NH—)—, —NHC(═O)N(—C(═O)NH—)—, —C(═O)NHC(═O)NH—, or —NHC(═O)NHC(═O)—,
• R1=H or C1- to C4-alkyl,
• R2=C1- to C4-alkyl,
• a=2 or 3,
• b=0 or 1,
• c=1 or 2,
• f=1 to 5, and
• a +b+c=4,
• and wherein silane (a3) has the formula (R1O)aR2bSiArc, wherein
• R1=H or C1- to C4-alkyl,
• R2=C1- to C4-alkyl,
• Ar=aryl wherein different Ar groups may be the same or different,
• a=2 or 3,
• b=0 or 1,
• c=1 or 2,
• a +b+c=4,
• (B) fillers, and
• (C) initiators, catalysts, activators, or combinations thereof, for polymerization.