Nickel-titanium: options and challenges.

The introduction of nickel-titanium (NiTi) as material for endodontic instruments about 15 years ago opened many new perspectives. Many dentists and scientists see a benefit in using NiFi files. Initial problems such as frequent fractures and the uncertainty of the best way to use them have been solved. Other challenges such as enhancing the cutting ability or optimizing the speed, torque, and fatigue are currently being addressed. Some clinicians are skeptical because they see this approach as too mechanical. Nevertheless, the combination of anatomic, biologic, and pathophysiologic knowledge with the use of NiTi instruments is a large step forward in optimizing the quality of root canal treatment worldwide.