Prerequisites for proper curing.

The prerequisites for proper curing include: 1) sufficient light intensity at 2) a certain wavelength, for 3) a certain time interval. This review discusses the radial output by halogen, PAC and LED lights, and the adaption of this output to meet the wavelength prerequisites for optimum polymerisation. Some basic terminology relating to the power of the light and intensity is explained and calculations are used to illustrate to the reader how the size of the light guide increases or reduces the intensity of the light beam.