The contemporary aspect of endodontic treatment is aimed at application of innovative techniques and materials, establishing biological processes and tissue regeneration, in order to preserve the masticatory, aesthetic and phonetic function of teeth. Radiological diagnostics is indispensable in endodontics. With the most common use of two-dimensional imaging, 3D imaging allows better visualization of dental structures, therefore CBCT is used as a modern imaging technique for the purpose of better and more reliable representation of individual structures and clinical situations. Stainless steel hand instruments extend the duration of therapeutic procedure, canal transportation is more likely to occur, and instruments are less adaptable to curved canals due to their rigidity. With the development of nickel-titanium (NiTi) alloys and engine-driven instrumentation techniques, faster and better instrumentation of root canals is achieved. Activation of the intracanal solution for chemical treatment and disinfection of root canals allows a better flow and treatment of the complex intracanal system after mechanical cleaning. Compared to conventional rinsing techniques, the removal of debris and smear layer is improved and bacteria are significantly reduced. The success of endodontic treatment also depends on the three-dimensional sealing of the root canals, which should enable a biological response by healing of the area modified by inflammation. Today the emphasis is placed on the application of bioactive and regenerative materials due to the fact that their antibacterial and biocompatible properties allow a strong bond with the tissue and stimulate its regeneration. Endodontic treatment ends with placement of the permanent restoration, whereas timely tooth reconstruction is a necessary prerequisite for the preservation of teeth and all their functions. The contemporary aspect of endodontic treatment, except the application of innovative therapeutic and diagnostic procedures, implies a dental treatment in a single appointment and control clinical and radiological follow-ups five years after the end of endodontic treatment.