Dental File, Hirschfield , FH 3-7. This Periodontal file is effective in crushing large calculus deposits so that the deposits can be more readily removed by a curette. Also, can be used to smooth the margins of amalgam restorations. These files feature a lightweight stainless handle to reduce stress on hands while providing superior tensile strength. The grip is ergonomically designed to limit stress on hands while providing maximum tactile sensitivity.