Internal Tooth Anatomy and Root Canal Obturation

  • Arnaldo Castellucci


The ultimate objective of the root canal therapy is the three-dimensional obturation of the endodontic space after it has been completely cleaned, shaped, and disinfected. The purpose of obturation is to seal all “portals of exit” to impede any sort of communication or exchange between the endodontium and periodontium. It must therefore completely and durably fill the root canal space, in which no empty spaces should remain at all. It has been repeatedly demonstrated that most of endodontic failures are related to incomplete obturation of the endodontium. On the other hand, it is well known that the root canal system can be disinfected and not sterilized. For this reason, the canal obturation should be considered like the very last step of cleaning, because it represents the only way to neutralize the bacteria left in the root canal walls and in the dentinal tubules. Understanding the biological reasons why a cleaned, shaped root canal requires to be obturated will guide in selecting the best filling materials and techniques.


Endodontic sealer Gutta-percha Lateral canal Obturation Root canal system 


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Authors and Affiliations

  • Arnaldo Castellucci
    • 1
    • 2
    • 3
  1. 1.Private Practice Limited to EndodonticsFlorenceItaly
  2. 2.EndodonticsUniversity of Cagliari Dental SchoolCagliariItaly
  3. 3.Micro-Surgical Endodontics, Specialty of Oral SurgeryUniversity Federico II of NaplesNaplesItaly

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