The purpose of this study was to evaluate the insertion depth of several brands of master gutta percha cones after shaping by various Ni-Ti rotary files in simulated canals.

Fifty resin simulated J-shape canals were instrumented with ProFile, ProTaper and HEROShaper. Simulated canals were prepared with ProFile .04 taper #25 (n = 10), .06 taper #25 (n = 10), ProTaper F2 (n = 10), HEROShaper .04 taper #25 (n = 10) and .06 taper #25 (n = 10). Size #25 gutta percha cones with a .04 & .06 taper from three different brands were used: DiaDent; META; Sure-endo. The gutta percha cones were selected and inserted into the prepared simulated canals. The distance from the apex of the prepared canal to the gutta percha cone tip was measured by image analysis program.

Within limited data of this study, the results were as follows

1. When the simulated root canals were prepared with HEROShaper, gutta-percha cones were closely adapted to the root canal.

2. All brands of gutta percha cones fail to go to the prepared length in canal which was instrumented with ProFile, the cones extend beyond the prepared length in canal which was prepared with ProTaper.

3. In canal which was instrumented with HEROShaper .04 taper #25, Sure-endo .04 taper master gutta percha cone was well fitted (p < 0.05).

4. In canal which was instrumented with HEROShaper .06 taper #25, META .06 taper master gutta percha cone was well fitted (p < 0.05).

As a result, we concluded that the insertion depth of all brands of master gutta percha cone do not match the rotary instrument, even though it was prepared by crown-down technique, as recommended by the manufacturer. Therefore, the master cone should be carefully selected to match the depth of the prepared canal for adequate obturation.

This study was conducted to evaluate the insertion depth of Buchanan plugger after shaping by various Ni-Ti rotary files. It was conducted to determine which size of plugger are appropriate, when root canals are shaped with Ni-Ti rotary files and obturated by Continuous wave of condensation technique.

Two type of eighty simulated resin blocks were used : J-shaped and straight shaped canal. The simulated canals were instrumented by ProTaper and ProFile. Buchanan pluggers were inserted into the canal, and then the image was recorded to scanner. The distance from the apex of the canal to the plugger tip was measured by image analysis program. Data were analyzed by one-way ANOVA followed by Scheffe's test.

The results were as follows

1. In straight canal finished up to ProTaper F2 and F3 file, F and FM pluggers were inserted more than 5 mm short of working length.

2. In J-shaped canal finished up to ProTaper F2 file, F pluggers were inserted more than 5 mm short of working length. Finished up to ProTaper F3 file, F and FM pluggers were inserted more than 5 mm short of working length.

3. In straight and J-shaped canal finished up to ProFile .06/#20 and .06/#25, any of Buchanan plugger could not be inserted more than 5 mm short of working length.

These results suggest that canals shaped by ProTaper could be obturated by Continuous wave of condensation technique with F and FM size Buchanan plugger.