Cleaning of endodontic root canal by ultrasonics and Nd:YAG laser beam with fiber optic delivery: scanning electron microscopy, endoscopic and microradiographic analysis

12 teeth have been extracted and treated 'in vitro' by ultrasonics and Nd:YAG pulsed laser with fiber optic delivery to compare the cleaning efficiency of the root canal. The optic fiber was equipped with a water-air coaxial cooling system. The ultrasonic device was equipped with a 3 percent NaCl solution douche system. The samples have been prepared according to the technical specifications of the suppliers of laser and ultrasonics and observed by an endodontic endoscope. Cross sections of the samples have been utilized for microradiographic investigations and scanning electron microscopy observations. Local melting has been observed after laser irradiation.Also, vitrification preferentially occurred in the apical zones. The occurrence of vitrification was found strongly dependent on the translation velocity of the laser beam inside the root canal. The laser beam has shown a cleaning efficiency greater than that obtained by ultrasonic procedure.