A comparative photoelastic stress analysis of internal root stresses between RC Prep and saline when applied to the Profile/GT rotary instrumentation system.

The purpose of this study was to measure and compare the amount of stress produced by GT ProFile (GT) and ProFile (PF) rotary files lubricated with either RC Prep (RCP) or saline (S) on the walls of prepared simulated canals. Twenty-four 10-mm long canals with a 10 mm radius of curvature were prepared in PL-2 photoelastic acrylic blocks which were lubricated with either RCP or S. The files were inserted into a Nouvag handpiece mounted to an Instron 4502 universal testing machine and lowered into the canal at a rate of 60 mm/min and a rotational speed of 300 RPM.