Cyclic Fatigue Resistance of Three Different Rotary Endodontic Instruments with Design Modification
Author(s): Ali S Abu Naila* and Hussain F Al-Huwaizi
Background: CF (Cyclic Fatigue) resistance of Dentsply Pro Taper Universal (PTU), Pro Taper Gold (PTG), and Pro Taper
Next (PTN) nickel titanium (NiTi) rotary files was evaluated in comparision with simulated files with same design and our
Methods: For PTU and PTG study design modification is to leave the apical 8 mm of S1 and the apical 3 mm of S2 as unmilled,
F1 only the apical 5 mm would have cutting blades. For PTN is to leave the apical 8 mm of X1 and, while for X2 is to
leave the coronal 8 mm as un-milled. Ten instruments for each file (S1, S2, F1, X1 and X2); total 240 files (80 pieces for
Dentsply, 80 pcs for simulated and 80 pieces for study design), files rotated in simulated canal until fracture.
Conclusion: PTG instruments were most resistant to CF, followed by PTN and PTU. S1 and S2 files making the non-active
part plane will increase CF resistance while for F1 files will decrease CF resistance. For PTN files groups, for X1 files making
the non-active part plane will increase CF resistance while for X2 files will decrease CF resistance.