With every passing day, demand of esthetic restoration is gaining momentum; which has made esthetic materials like composite resin the restorative material of choice. Methods and devices to cure composite resin have evolved jointly; passing from chemically cured resins to modern form of light cured composite resins. Success and predictability of composite resin restorations depends on one major factor i.e. degree of resin polymerization achieved during its placement in the prepared cavity.The ability of light curing units to deliver enough light at appropriate absorption spectrum is crucial...