COMPARISON BY MEANS OF A COMPUTER-SUPPORTED DEVICE OF THE ENLARGING CHARACTERISTICS OF 2 DIFFERENT INSTRUMENTS

Numerous studies report different results when testing endodontic inst ruments with similar and/or different research protocols. However, obj ective studies that could eliminate the factors inherent to the operat or have not yet been developed. Simulated root canals in clear casting resin were used as models. The Canal Master U and Flexogate were test ed by using a double exposure photographic technique. A computer-aided device capable of reproducing three-dimensional enlarging movements a nd irrigation of the simulated canals was developed. The enlarging mov ements were programmed according to the step-back and step-down techni ques. The enlarging of simulated root canals with this device proved t o be constant and reproducible. Standard deviations were kept low and were dependent on the degree of canal curvature. The enlarged simulate d root canals showed that both instruments could be kept centered in t he path of the root canal. Results showed only a few significant diffe rences between the effective material removed and a theoretical ideal amount of removed material.