•Purpose: To describe a novel canal preparation technique using only one Ni-Ti rotary instrument
•Canal negotiation with #8 file, in severely curved canals to #10 or #15.
•CW and the CCW rotations are set on the motor at 4/10 and 2/10 of a circle. speed is set at 400 rpm.
•F2 protaper is used in reciprocating movement.
•in narrow/curved canals no further instrumentation required.
•In straight canals further enlargement can be done with hand files.
•2.5% NaOCl and a final rinse with EDTA 17% followed by NaOCl.
•presence of a sharp (non-gradual)canal curvature, in which hand instrumentation should be used to complete apical preparation.
•2 major advantages of this technique: reducing cross contaminating through a single use of 1 file (cost –effective)