An improved technique for the evaluation of root canal preparation.

A device and a method are described for the simultaneous in vitro evaluation of several important parameters of root canal preparation, including root canal cleanliness, straightening, changes in root canal diameter, working safety (loss of working length, apical blockage, instrument fracture, and apical perforation), measurement of apically extruded debris, working time, and practicability. Using a modification of the muffle system described by Bramante et al. (J. Endodon, 13:243-5, 1987), all of these parameters can be investigated simultaneously during preparation of two mesial root canals in extracted mandibular molars.