An evaluation of the crown-down pressureless technique

By Morgan LF, Montgomery S

Date: 01/1984
Journal: JOE


To determine whether ledging, zipping, and perforation occur more frequently in curved canals using crown down pressureless technique vs. traditional filing.


  • n=40 single canal extracted human teeth with apical curvature 10-35 deg.
  •  mounted in typodont, half instrumented with crown-down technique and half using traditional hand filing.
  •   5 similar uninstrumented teeth served as controls.
  •   injected xantopren blue impression material into root canal systems under vacuum and teeth cleared.
  •   5 different evaluators (4 endos, 1 GP) gave an overal rating of quality


  • significant difference only in overall rating.
  • crown down technique received more excellent ratings and was deemed an effective method for instrumenting curved canals (P= .02)

Clinical Significance:

Crown down instrumentation may allow easier preparation of curved canals.