Sandhya Kapoor Punia , Vikas Punia , Vivek Sharma , Meenakshi Khandelwal 

ABSTRACT

Stress generation at tissue/resin composite interfaces is one of the important factors for failure of resin-based composite (RBC) restorations owing to the inherent property of polymerization shrinkage (PS). Polymerization shrinkage of resin composites invariably generates a degree of stress at the tooth/restoration interface. The magnitude of the stresses so produced depends on resin composite composition and its ability to flow before solidification, which is, in turn related to cavity configuration and curing characteristics of the composite. These unrelieved stresses can weaken the bond between the tooth structure and the restoration, eventually producing a gap at the restoration margins. This can lead to postoperative sensitivity, secondary caries, fracture of the restorations, marginal deterioration and discoloration. The objectives of this article are to review the mechanism of polymerization shrinkage, the clinical factors affecting polymerization stress, and methods advocated to reduce shrinkage stress. This article emphasize on minimizing the shrinkage stresses in RBC restorations to improvement in the success rate and survival of restorations. Thus, it is important for dental practitioners to be aware of various techniques and materials available to reduce these shrinkage stresses and be updated with the current knowledge available to deal with this issue.