Zinc and sodium high pressure lamps for curing composite resins.

Polymerisation characteristics of conventional units for curing composite resins are insufficient considering handling feasibilities particularly in the premolar and molar region. There is also hazardous ocular effect of near ultra-violet part of visible spectra. Sodium high pressure lamp technology has been applied to develop a new high pressure zinc lamp, which is for the first time used for curing composite materials. The results of polymerisation measurements show that future improvements over the usual halogen light sources are possible. Zinc lamp was also compared with the high pressure sodium lamp filled with mercury or cadmium.