A comparative study on the effect of three methods of instrumentation on the shape of root canal (an in-vitro study)

This study compared the ability of three types of engine driven instrumentation techniques to negotiate and prepare small, slightly curved root canals. Forty five mesial roots of extracted maxillary and mandibular first permanent molars were classified into three groups. Group (I) was prepared by Canal Leader system, group (II) was prepared by Nickel Titanium files and group (III) was prepared by Canal Master technique. Radiographs of the root canal space before and after preparation was carried out by the aid of an experimental model. Enlarged photographic prints obtained from radiographs were scored for shaping effectiveness of the three techniques in respect to canal course, position & width of apical constriction and lack of ledge formation. The results indicated that the Canal Leader system was an efficient technique in maintaining canal curvature, absence of zipping, transportation or ledge formation in almost all of the specimen tested, followed by the Nickel Titanium files and then the Canal Master technique which produced more straightening and destruction of apical constriction.