NiTi Files (Nickel-Titanium Files) – Sizes 15–40

NiTi Files are nickel-titanium rotary or hand instruments used in endodontics for cleaning and shaping root canals during root canal treatment (RCT). The sizes 15–40 refer to the tip diameter (ISO sizes) of the files, with 15 being thinner and 40 thicker, allowing for progressive enlargement of the canal.

They are preferred over stainless steel files because of their superelasticity, flexibility, and resistance to fracture, especially in curved canals.