ABSTRACT
After the invention of the laser in 1960, its medical applications interested Hungarian physician Endre Mester. He used a lowlevel red (632.8 nm) He-Ne laser to irradiate animals and, eventually, people. His early work showed that wound healing was accelerated by laser irradiation (Mester et al. 1968, 1971), from which interest in low-level laser therapy (LLLT), also known as low-power laser therapy (LPLT), biostimulation, low-energy laser irradiation (LELI), cold laser, and photobiomodulation of both humans and animals spread from Europe to most of the world. These methods were applied to numerous ailments (Tata and Waynant 2011). Since 1960, more and more researchers have been involved with LLLT, which has become one of the many techniques utilized in modern phototherapy (Tata and Waynant 2011). Specialists and general practitioners use LLLT to treat a broad range of conditions, but the most common indications are local pain relief (Gur et al. 2004), anti-inflammation (Antunes et al. 2007), and wound healing (Posten et al. 2005). Initially, how LLLT worked for the treatment of different conditions was nothing but a mystery, and without information about its mechanism of action, efficient manipulation of LLLT was difficult.
