The ProTaper system is comprised of three shaping (SX, S1 and S2) and three finishing (Fl, F2 and F3) files. A maxillary second molar and a mandibular second premolar were shaped with ProTaper files, and smooth uniformly tapered canals were created more easily than with stainless steel hand files. During use of NiTi rotary files, it is necessary to consider their potential for breakage. In order to prevent breakage, ProTaper files have a unique design, including multiple tapers, a convex triangular cross-section, a continuously changing pitch and helical angle, and a modified guiding tip. Furthermore, the files are combined with an EndoTecnika motor, programmed to allow torque selection for each ProTaper file, which increases safety. Consequently, it is believed that the ProTaper system is very useful in preparing root canal treatment.
