- Purpose: to evaluate the effect of preparation taper using size #20 or size #40 ProFile GT files on the ability to introduce irrigant and subsequently remove debris from the apical extent of root canals.
- N= A total of 104, bilaterally matched, freshly extracted, human teeth were collected.
48 pairs were divided into four groups Group 1 was instrumented with .04-tapered instruments, group 2 with .06-tapered instruments, group 3 with .08-tapered instruments, and group 4 with .10-tapered instruments. within each taper category one tooth was prepared to size #20 and the other to size #40.
Sections were viewed with a light microscope. The amount of debris remaining in the canal was quantified using the NIH Image V1.56 software program.
Most highlighted Results:
1.Size #40 preparations resulted in less residual debris compared with the #20 preparations in the .04-, .06-, and .08-taper categories. However, taper .10,showed no significant difference between the #20 ( preparations.
2.Within #20 preparations, needle penetration in the .10- and .08-tapered groups was significantly greater than the .04- and .06-tapered categories.
3.The number of instrument changes necessary to reach WL was significantly greater for the #40 preparations in all taper categories.
4.A total of 5.0 ml of NaOCl was used to irrigate each of the size #20 preparations, whereas 5.5 to 5.9 ml was used to irrigate the size #40 preparations. This difference was statistically significant.
Debris is more effectively removed using .04, .06, and .08 ProFile GT instruments when the apical preparation size is larger (size #40) compared with size #20 apical preparations