Shaping ability and safety of five different rotary nickel-titanium instruments compared with stainless steel hand instrumentation in simulated curved root canals.
OBJECTIVE
To compare the shaping ability and safety of engine-driven FlexMaster, GT Rotary, ProFile, ProTaper, and RaCe rotary instrumentation and Hedström hand instrumentation in simulated root canals.


METHODS
One hundred fifty simulated colored root canals with a curvature of 20 degrees and a radius of 10 mm were randomly distributed among 6 groups of 25 specimens each. After preparation to apical size 30 the area of remaining color on the canal wall indicating unprepared areas was measured in mm2 using image analyzer software.


RESULTS
Specimens treated with RaCe left least areas of remaining color compared to all other groups (P < .001), followed by ProTaper. Preparation with ProFile left behind the highest amount of unprepared areas. The ProFile group revealed significantly more remaining color than ProTaper, GT Rotary, and FlexMaster (P < .05). Four FlexMaster files separated.


CONCLUSIONS
RaCe rotary files were safe and more effective compared to the other instruments.
Schirrmeister
Jörg F
JF
Department of Operative Dentistry and Periodontology, Albert-Ludwigs-University of Freiburg, Freiburg, Germany. joerg.schirrmeister@uniklinik-freiburg.de
Strohl
Christian
C
Altenburger
Markus J
MJ
Wrbas
Karl-Thomas
KT
Hellwig
Elmar
E
D003722:Dental Alloys; D003762:Dental Instruments; D003799:Dental Stress Analysis; D004868:Equipment Failure; D004869:Equipment Safety; D003765:Models, Dental; D009532:Nickel; D012117:Resins, Synthetic; D018915:Root Canal Preparation / Q000295:instrumentation*; D013193:Stainless Steel; D018709:Statistics, Nonparametric; D014025:Titanium
D003722:Dental Alloys; D012117:Resins, Synthetic; C040654:titanium nickelide; D013193:Stainless Steel; D009532:Nickel; D014025:Titanium