Photopolymerization shrinkage: strategies for reduction, measurement methods and future insights

Abstract

Herein, a review of the literature on polymerization shrinkage occurring in dental composites was presented. In particular, methods of reducing polymerization shrinkage in dental composites by using alternative monomers and photoinitiators were described. Thus, new alternative materials for use in polymerization processes to obtain composites with limited polymerization shrinkage were presented. The effects of time and type of setting, as well as the type and amount of inorganic fillings, on the value of polymerization shrinkage were also discussed. It was explained why standard dental composites exhibit high polymerization shrinkage and why volume shrinkage and shrinkage stress are key factors in determining the quality of polymeric materials for dental applications. Traditional and new methods for testing polymerization shrinkage of composites were also presented. The advantages and disadvantages of methods for measuring polymerization shrinkage in dental composites were also presented and future insights were highlighted.