2004 Volume 25 Issue 2 Pages 67-71
Abstract : Generally, the form of a root canal on cross section at the coronal side and/or the middle 1/3 shows an ovoid type, except for the upper central incisor and the palatal root of the upper first molar in the medio-distal view. Recently, Ni-Ti files were developed for speedy and safe root canal shaping. When using Ni-Ti files, a low-speed rotary engine is used in the clinic. It is useful for shaping a circle-type root canal on cross section. However, they cannot shape an ovoid-type root canal on cross section, completely. We developed a new root canal shaping system using 4 and 6% tapered stainless steel H-files (NHF) with a vertical stroke motion and a Ni-Ti file (GT Rotary) with rotary motion. With use of a GT Rotary, insufficient shaping or non-shaping parts have been found at the coronal side of a root canal, because the root canal cuts to a circle using a GT Rotary. However, it was clarified that the root canal system was securely shaped with combined use of NHF and a GT Rotary.
