After opening the cavity access, localizing and widening the canal entrance, the canal can be penetrated with manual or rotary files made of steel or Niti to allow probing and debridement of the canal. Depending on the canal morphology, this step of the procedure is undertaken using one or several of the following instruments.
1. Hand files
The hand endodontic files made of steel or NiTi in standard ISO sizes 6 to 40 have a rounded safety tip, which is an exclusive FKG feature, plus and also have an ergonomic handle, the SafetyMemoGrip (SMG). Thanks to its larger rear diameter, the ergonomic handle offers a better grip. Situated on the end of the handle is an 8-segmented “use” indicator. After each treatment, a segment is scratched, thus preserving information on the number of cycles of use and sterilization. When all segments are scratched, the instrument is discarded.
There are also so-called "Flex" manual steel files, which provide better flexibility. They are recognisable thanks to the small "F" affixed on their handle, just like the manual NiTi files.
The hand files are also available with the Ergoflex handle. Its particular ergonomic features, rounded section followed by a flat section, facilitate gripping when filing and prevent rotation above 180°.
Stainless steel hand files, ISO 6, 8 and 10 are for single use only.
2. Rotary NiTi instruments for mechanized scouting
NiTi rotary instruments allow a quicker and more reliable passage preparation than hand instruments.
Greater respect of the anatomy of the middle and apical thirds is observed without transport or formation of a stop. Due to their slight taper and extreme flexibility, NiTi rotary instruments follow perfectly the anatomy of the canal and are used without pressure up to the working length (WL), thus allowing better shaping of the canal.