Curing Lights 

1978-1995

Developed in the 1970s, the first curing lights emitted a type of ultraviolet energy that helped bond the composite resin to the tooth structure. This process known as photo-polymerization activates certain chemicals causing them to bond together and form a solid structure when exposed to blue light for a sufficient length of time. 

Over time, curing lights evolved, with halogen lights emerging in the 1980s and then LED curing lights becoming the dominant technology by the 1990s.