Alloys for endodontic files and hand instruments

There has been considerable development in the endodontic instruments, which has resulted in better root canal instruments with the increased success of the endodontic treatment. The fundamental biomaterials for endodontic treatment include carbon steel (CS), stainless steel (SS), and nickel-titanium (NiTi) alloy. NiTi instruments are increasingly used due to flexibility and shape memory effect. In contrast, CS and SS instruments are more laborious and stiffer with less flexibility than NiTi alloy. Recent developments in NiTi rotary instruments include controlled memory (CM) wire and R-phase wire with improved flexibility and fatigue resistance, and surface improvements. The advantages of these technologies bring faster and more efficient instrumentation with resistance to cyclic fatigue, cutting efficiency, and decrease canal transportation and ledging. The clinician should be familiar with different endodontic instruments as new instruments are introduced regularly. This chapter focuses on the biomechanics of endodontic instruments and presents recent developments in various alloys for endodontic instruments.