Related Experiment Video
Updated: Aug 20, 2026
Mimicking and Measuring Occlusal Erosive Tooth Wear with the "Rub&Roll" and Non-contact Profilometry
Published on: February 2, 2018
Analysis of forces developed during mechanical preparation of extracted teeth using RaCe rotary instruments and
F M da Silva1, C Kobayashi, H Suda
1Pulp Biology and Endodontics, Department of Restorative Sciences, Graduate School, Tokyo Medical and Dental University, Tokyo 113-8548, Japan. fabiendo@tmd.ac.jp
Aim:
To compare the torque and load during instrumentation with ProFile and RaCe nickel-titanium rotary instruments.
Methodology:
Thirty human incisor roots 12 mm in length were embedded in epoxy resin, and divided into three groups of 10 specimens each. Instruments employed in each group were as follows: RaCe .02 Step Back Files in group 1; RaCe .04 Step Back Files in group 2; and .04 ProFiles in group 3. Two load cells, whose outputs were connected to a digital oscilloscope, recorded torque and vertical load. Data were analysed by one-way anova.
Results:
Torque values were statistically different between groups 1 and 3, and between groups 2 and 3 (torque was higher in group 3 than in groups 1 and 2). Vertical loads were statistically higher in group 3 than in groups 1 and 2.
Conclusions:
Torsional and vertical forces can be evaluated during instrumentation of straight root canals using the device and methods described in this study. When the step-back technique was employed, torque and vertical load obtained with RaCe instruments were lower than that obtained with ProFiles.
