Effect of the composite curing light mode on polymerization shrinkage of resin composites

Abstract

Objectives: The aim of this study was to investigate the effects of light curing method on the polymerizationshrinkage of composite resins. Materials and Methods: Eight methods of four different light curing units were tested by forming 16 groupsusing two different composite types. Resin composite specimens weights were determined with an analyticalelectronic hydrostatic balance in the air and in water before and after curing. Then specific gravity values weredetermined. Volumetric polymerization shrinkage was calculated using mathematical formulas.Results: According to the results of this in-vitro study, polymerization shrinkage differed significantly amongthe light curing units. Conclusions: When the amount of polymerization shrinkage was compared, it was determined that the curingmethod, which has the greatest total energy density, caused the greatest amount of shrinkage. It was also foundout that some of the curing units affected the shrinkage positively in soft-start mode.