Riva Self Cure does not contain resin eliminating the problem of volumetric shrinkage after curing. Sensitivity, resulting from microleakage associated with shrinkage does not occur. Riva Self Cure easily extrudes into the cavity, but for an exceptional packable, high viscosity material, use Riva Self Cure HV. You have a choice. Riva Self Cure can be bulk filled to minimize chair time.