Although the standard of living is getting higher, there is still a high incidence of caries which, if not repaired in time, can affect the pulp and cause its necrosis. Then, endodontic therapy is needed, which includes: diagnostics, tooth isolation, formating an access cavity, mechanical cleaning and shaping of the root canals, chemical cleaning, hermetic filling of the root canals, and finally functional reconstruction. A good postendodontic supply of the treated tooth is essential for the success of endodontic therapy. The tooth must remain a functional part of the masticatory system. Due to caries or trauma and the formation of the access cavity, there is a great loss of tooth structure, and proper functional reconstruction becomes difficult. To compensate for this loss and improve retention, sometimes it is necessary to place posts. Despite some present opinions, the post does not increase the tooth's resistance to fracture, on contrary, it weakensit. Especially if it is not the appropriate post to the case. It is necessary to provide a minimum of 1mm thick dentin around the post. Of great importance in successful functional reconstruction is the presence of ferrule. Ferrule enhances the resistance of teeth to fractures, even if it is not possible to obtain it in the full circumference, ie it is not continuous.