The Complexity of the Apical Anatomy

  • Domenico RicucciEmail author
  • Elizeu A. Pascon
  • José F. SiqueiraJr.


The apical portion of the root canal system is characterized by a very complex and variable anatomy. The main canal displays a constriction located slightly short of the main apical foramen, but ramifications are common. After pulp exposure by caries, necrosis and infection progress slowly in an apical direction and give rise to apical periodontitis, even before the pulp is completely necrotic and infected. Bacteria infecting the apical portion of the root canal system are the main cause of posttreatment apical periodontitis. The ideal apical limit of endodontic procedures is the apical constriction, but this structure is not always present. Pathologic changes, such as resorption of the apical root structure and canal calcification, may make it difficult to establish an adequate working length for endodontic procedures. In the light of the histological and microbiological conditions of the apical pulp tissue, the apical patency concept seems justified in cases with pulp necrosis/infection.


Apical ramifications Apical constriction Apical patency Apical limit Bacteria Cementum-dentin junction Pulp necrosis Pulp histology Root canal anatomy Root resorption 


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Copyright information

© Springer International Publishing AG, part of Springer Nature 2019

Authors and Affiliations

  • Domenico Ricucci
    • 1
    Email author
  • Elizeu A. Pascon
    • 2
  • José F. SiqueiraJr.
    • 3
  1. 1.Private PracticeCetraroItaly
  2. 2.Private PracticeSão PauloBrazil
  3. 3.Department of Endodontics, Faculty of DentistryEstácio de Sá UniversityRio de JaneiroBrazil

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