Light curing--an update.

Light-cured, resin-based composite is an integral part of esthetic and restorative dentistry. This article reviews the performance and limitations of 4 types of curing lights and predicts that curing lights of the future will use light-emitting diode (LED). Currently, LED curing lights are not as powerful as plasma arc curing (PAC) or quartz tungsten halogen (QTH) lights.