In recent years, different laser systems are used in endodontic field, which are effective for root canal disinfection. The diode laser is a compact device and now used in diverse areas of dentistry.
The high-power diode laser reduces dentine permeability, although it does not provoke the dentine melting unlike neodymium laser. The diode laser device is composed of two layers of semiconductor material interlaced with a non-conductive layer. Its light presents a spectrum that allows for greater absorption by water than dental tissues when compared with Nd: YAG laser. This characteristic means greater laser light penetration through the dentin with little interaction on the dentin, making it possible to act on the microorganisms present in the dentinal tubules. The fine diameters of optic fibers (200㎛) enable effective delivery of laser light to the root canal to help with reduction of bacterial contamination. The antibacterial effect observed reaches over 1 mm deep into the dentin, surpassing the effective range of chemical disinfectants, such as NaOCl and displaying moderate effectiveness against E. fecalis even in the deeper layers of dentin. Diode laser effectiveness in relation to diverse microorganisms has been demonstrated by many authors.
The Pioon diode laser at 980 nm can eliminate bacteria that has immigrated into dentin, thus being able to increase the success rate in endodontic therapy.