Root canal treatment is performed in our clinic with the use of an endodontic microscope. The procedure is completed in one session. It is preceded by a diagnostic X-ray examination in the RVG technology. The root canals are debrided mechanically with the use of module Dentaport Tri Auto ZX and filled with liquid gutta-percha by System B and Obtura II. The filling effectiveness is controlled by means of RVG.