si7es e.in at ISO 334 and ran.e to si7e :4 *he heads are very
short?only 234 mm for
the si7e 32 and up to %;4 mm for the si7e %22
It is recommended that the I
selected rpm remain constant As with many of the new rotary
instruments,
this speed calls for a controlled, preferaly electric handpiece
One of I
touted advanta.es is the aility to finish the apical-third
preparation to a lar.er si7e if
dictated y the canal diameter It has een said that 6canal
diameter, particularly in the
apical third, is a for.otten dimension in endodontics8 "personal
communication, Dr 0arl
!awrish, %&&&(
8/10/2019 u file
3/3
Figure 10-25 A, Cross-sectional view of a U File reveals six
corners in cutting bladescompared with four corners in square stock
and threecorners in triangular stock K les. B, Nickel-titanium
-shaped les in C-shaped molar canals.Note extreme !exibilit"
(arrow) without separation.#A courtes" of $erek %eath, &ualit"
$ental 'roducts. B courtes" of $r. (ohn )c*padden.+
Figure 10-26he unusual LightSpeed instrument. shaped indesign
with a noncutting tip, the /ight*peed utting head terminatesa 01 mm
noncutting shaft.)ade onl" in nickel titanium in 2*3si4es 56 to 066
and in half si4es as well, the" are used in rotar" preparationsat
5,666 rpm. #Courtes" of /ight*peed echnolog" 2nc.+
