Journal of Dental Research, Vol 69, 1617-1621, Copyright © 1990 by International & American Associations for Dental Research Online Journals
Statistical models for evaluating the penetrating ability of endodontic instruments
C. Fuchs, C. Friedlander, E. Rosenberg and A. Tamse
Department of Statistics, School of Mathematical Sciences, Sackler Faculty of Exact Sciences, Tel Aviv University, Israel.
An in vitro study was conducted to evaluate the penetrating ability of hand
instruments (No. 10 K-file and "Pathfinder") and an automated device with a
No. 08 (Canal Finder System) file in 270 extracted curved and narrow molar
roots. The roots were randomly allocated to six groups, each one
corresponding to a different permutation of the three instruments. The
experiment was performed in three sequential stages, and Stages II and III
were undertaken only in roots where no apical penetration was achieved in
the previous stage(s). Statistical models were designed to fit the
resulting clinical data. The No. 08 Canal Finder System and No. 10 K-file
proved to be similar in their penetrating ability in Stage I (with
estimated probabilities of 71.1% and 68.8%, respectively). The No. 08 Canal
Finder was found to be the most efficient in Stage II and especially in
Stage III, with a probability of penetration of 20.7%, compared with 9.8%
for the "Pathfinder" and 7.4% for the No. 10 K-file.
