Nickel-titanium (NiTi) is a superelastic alloy, enabling it to withstand higher stresses than stainless steel—significantly lowering endodontic file fracture risk. It also boasts "shape memory": post-strain, heating restores its original shape, eliminating compression/tension forces and reducing root canal deformation.
NiTi’s superelasticity supports a 4–8% taper (higher than stainless steel), ensuring adequate root canal taper. This cuts preparation time and reduces the number of files required. Additionally, it minimizes zipping and apical transportation risks.
Widely available, NiTi files suit both rotary systems and manual use (for enhanced control).
