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Defense Date


Document Type


Degree Name

Master of Science



First Advisor

Dr. Frederick R. Liewehr


The purpose of this study was to examine the effect of immersion in sodium hypochlorite on nickel titanium rotary files and determine whether resistance to fracture was influenced by the immersion time. 70 ISO size 25 0.04 taper nickel titanium K3 and Profile rotary instruments were immersed in 5.25% sodium hypochlorite for 1, 5, 15, 30, 60, and 120 minutes (n=5 each). Resistance to fracture was tested by rotating files at a 30 degree angle at 350 rpm in a universal testing machine. Time to fracture was recorded and analyzed by a two-way ANOVA. Within both file types, there was a decreased time to fracture with increased immersion time in sodium hypochlorite. K3 files required an average of 327 rotations to fracture, while Profiles required 420 rotations to fracture. Profiles required significantly more rotations to failure than K3 files.


Part of Retrospective ETD Collection, restricted to VCU only.


© The Author

Is Part Of

VCU University Archives

Is Part Of

VCU Theses and Dissertations

Date of Submission

June 2008