Nd:YAG, Erbium Lasers and diodes have been studied extensively as an adjunct to endodontic treatment. Many of these studies have shown improved smear layer removal and disinfection in the apical third of the tooth. There is the concern of negative thermal effects within the confined space of the root canal.
Recently a phenomenon known as PIPS (Photon Induced Photoacoustic Streaming) has been discovered. The extremely high peak power and affinity for water of the Er:YAG laser creates an interesting phenomenon when specially shaped radial firing tips are place in irrigant solutions. When these special tips are submerged in solution each pulse sends a powerful wave of acoustic energy throughout the solution. The laser is used at a setting that creates very little thermal effect. The resultant shock wave propagates throughout the complete three-dimensional root canal system, even the tiniest accessory canals. Scanning electron microscope and microbiological studies have shown extremely thorough cleansing and disinfection of the total root canal complex.18,19 The PIPS technique allows the dentist to instrument less aggressively and still achieves a thoroughly clean root canal system.