Premise Research

Shrinkage in Composite

Shrinkage in a composite is caused by the change in dimensions as the resin cures. The molecules come together to form bonds with each other; therefore, the lower the proportion of resin (higher proportion of filler or higher loading) in a composite, the lower the shrinkage will be.

Composite manufacturers that claim ultra-low shrinkage values typically use large-particle fillers to get a high loading; however, this also results in poor polishability and non-retention of luster during clinical use.

With Premise, we took the approach of incorporating a PPF that acts as a large-particle filler to give it physical properties equivalent to a hybrid. This PPF is composed of cured resin loaded to 81% with submicron fillers. The composition of the PPF in Premise is very similar to the final paste: barium glass and silica filler with an average particle size of 0.4 µm and resin.

Since the particles are so small in size, we also incorporate 0.02 micron filler as the third filler component.

Premise Universal Restorative vs. Leading Brands

1.6% Shrinkage High filler load reduces shrinkage up to 36% less than four leading brands. This reduced shrinkage provides greater peace of mind when placing larger increments (due to less stress from curing).