Copyright © 1996 by The American Association of Endodontists
Printed in U.S.A. VOL. 22, NO. 8, AUGUST1996
Canal Transportation Caused bya New Instrumentation Technique and Three Standard Techniques
Benjamin Brisefio Marroquin, DDS, Alexander Pistorius, DDS, and Brita Willershausen-Z6nnchen, DDS
The ability of three differentenlarging techniques (balanced force concept, step-back, and recapitulation) and a prototype system to maintain the original canal path during root canal preparation were compared, in vitro, with atheoretical ideally prepared root canal. Measurements were made at the concave and convex sides of the canal at four different levels (1, 4, 5, and 7 mm from apical, respectively). Simulated root canalsembedded in clear casting resin and an enlarging computersupported device were used for this study. The results showed that none of the enlarging techniques used in this study was able to prepare a canalideally. The prototype system, at level 1, showed an ideal amount of material removed from the concave side and less, in comparison with the other techniques, from the convex side of the canals. Thesame tendencies persisted at all levels, with the exception of the level 4 concave side.
developed the Flex-R files to be used with the balanced force concept technique. They recommend clockwiseand counterclockwise movements in the root canal to avoid the formation of ledges and to attain suitable debris transportation in a coronal direction. Wildey and Senia (8) developed the Canal Master "U"System to be used with modifications of the step-down and step-back techniques. It is said that apical transportation is minimized through instrument cutting segment reduction. A new root canalpreparation system, which seeks the avoidance of ledging of the apical third, was presented a short time ago (9). However, research evidence that supports the theory postulated in this study has not been...