The light common in dental practices has several brand names, one of the bigger companies known as VELscope. They are all very specific blue spectrum lights, and work on the principal of tissue auto fluorescence. Human tissues contain fluorophors, which when agitated by this spectrum of blue light, or by certain chemicals fluoresce, or put out a glow when healthy. When a dentist looks into your mouth with that light while wearing some amber colored glasses, normal fluorescing healthy tissues look light green like a green apple. Cells that are damaged in some ways will not do this and appear black. This loss of fluorescence can be caused by things outside of dna damage related to malignancy, so it is not totally specific to finding cancer. But it helps identify areas that are suspect and maybe in need of further inquiry, perhaps through a biopsy, which will determine their condition through a different means under microscopic examination.
The Oral Cancer Foundation was an early sponsor of this research idea back in 2002-4 when it was being explored for use in cervical cancer at MD Anderson Cancer Center in Houston, Texas. We recognized early on what this opportunity would bring to the oral cancer world, which is heavily white light visual and tactile exams. Because the funding came from government (NIH) and a charity source, the published science was in the public domain. A Canadian company named LED was encouraged by OCF to look at the development of a hand held device to sell to the dental market. After doing so, and showing that it was a viable discovery (not diagnostic) device, other companies also entered the market place. OCF has frequently been at the forefront of sponsoring ideas that are breakthroughs as we are very connected to the research world and watch for new ideas to put our donor dollars towards.