The aim of this study was to compare polymerization lamps of various technologies (halogen, high performance halogen, xenon, i.e. plasma arc, as well as diode lamps) to determine the degree of polymerization of composite probes using Fourier-transform infrared (FTIR) spectroscopy. To observe the light-induced curing reaction under a bracket, an attenuated total reflection (ATR)-FTIR was used. T...