During the past few decades endodontic treatment has aided from the introduction of new techniques and equipment, among which the use of ultrasonic sources has now gained such importance in the economy of endodontic treatment that leads us to consider it as one of most interesting innovations introduced into modern endodontics. Ultrasonics is defined as waves with frequencies of at least 25 kHz, and are one of the most used non-invasive technology facilities in modern dentistry. In recent years, this type of technique has been popular, not only in endodontics but also in other branches of dentistry. Endodontics is the specialization in which ultrasound has enabled the most visible advancement to be made. Since its introduction, ultrasonics has become increasingly more useful in applications such as gaining access to canal openings, cleaning and shaping, obturation of root canals, removal of intracanal materials and obstructions and endodontic surgery.