Indium light source for curing composite resins

There is an existing problem of cumulative hazardous effect of violet and near ultra-violet light which is produced by standard polymerisation units. Another restrict is shallow depth of cure, particularly of darker composite shades in premolar and molar region. Searching for better light source we used indium resonance lines from several indium high pressure lamps and tested curing effect on three different composite resins. The overall results are better with the lamp in which two strong resonance lines of indium are present, rather than with a lamp with just one strong resonance line. The improvements in lamp design are necessary to overcome conventional polymerisation lamps.