Cleaning and Shaping the Root Canal

By Schilder H

Date: 01/1974
Journal: Symposium on Endodontics

Summary:

  • To achieve success of endodontic treatment, the root canal system must be cleaned and shaped (cleaned of organic debris and shaped to receive three dimensional hermetic filling of the entire root canal space).
  • The development of unique shape for every root canal, directly related not only to the length but to the position and curvature of each individual root and root canal.
  • The mechanical objectives of root canal shaping:
    • the root canal preparation should develop a continuously tapering funnel from the root apex to the coronal access cavity (to enhance cleaning, compacting of GP and flow of irrigants).
    • the cross section diameter of the preparation should be narrower at every point apically and wider at each point coronally. (to establish constriction apically)
    • the root canal preparation should flow with the shape of the original canal. (straitening should be avoided)
    • the apical foramen should remain in its original position. (transporting the foramen is associated with wet canal and cases of failure), It takes two forms, elleptical or tear drop and root perforation
    • the apical opening should be kept as small as practical. (to prevent extrusion of obturation material and tearing of PDLs)
  • the biological objectives of cleaning and shaping:
    • instruments confined to the root canals
    • all tissue debris should be removed from the root canal system.
    • complete cleaning and shaping of root canals in one visit.
    • create sufficient space during canal enlargement for intra canal medicaments.
  • Clinical preparation of the root canal:
    • by serial filing and reaming and recapitulation
    • by establishing patency and using of serials of larger files or reamers that inserted passively in the canal, the procedure repeated (recapitulation)