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. For the present, QTH curing lights dominate, but PAC lights cure increments of composite resin more efficiently. This article discusses different curing lights: QTH lights, PAC lights, laser curing units, and LED curing lights. The support for different curing modes (soft, exponential, and pulse delay) to improve marginal integrity and reduce marginal leakage is examined.