F. Goldberg et Ja. Araujo, COMPARISON OF 3 INSTRUMENTS IN THE PREPARATION OF CURVED ROOT CANALS, Endodontics & dental traumatology, 13(6), 1997, pp. 265-268
The transportation produced in the apical and middle areas of 30 mesio
buccal root canals of human mandibular molars was evaluated after circ
umferential instrumentation using stainless steel K-files (group A), n
ickel-titanium K-files (group B), and clockwise/counterclockwise file
rotation using Flexogates (group C). The canals were instrumented with
files #15 to #35 in size. Apical transportation was assessed radiogra
phically while that occurring in the middle area was studied microscop
ically in cross-sections. Although apical transportation was greatest
in the canals of group A, this difference was not statistically signif
icant (P>0.05). With respect to the middle area of the root canal, con
siderable transportation was observed in 7 of the 30 instrumented root
s. Of these, five belonged to group A and two to group B, a difference
which was not statistically significant (P>0.05). The best results fo
r transportation in the middle area of the canal were obtained in grou
p C, in which no transportation occurred. This difference was signific
ant when compared with the transportation observed in group A (P=0.02)
but not with that in group B (P>0.05).