Table 1.

Mean and standard deviation of the number of cycles to fracture (NCF) according to instrument type and temperature used.

Instrument type	20°C mean ± SD (CV%)	37°C mean ± SD (CV%)	P value
VB	1.899 ± 629.73(A)	1.033 ± 190.07(A)	P (1) < 0.001∗
XB	2.974 ± 449.12(B)	1.082 ± 374.19(A)	P (2) < 0.001∗
RB	5.419 ± 1,179.85(C)	2.019 ± 388.49(B)	P (1) < 0.001∗
P value	P (3) = 0.004∗	P (4) < 0.001∗

^∗Significant difference at 0.05. ⁽¹⁾Student's t-test with equal variances. ⁽²⁾Student's t-test with unequal variances. ⁽³⁾F (analysis of variance (ANOVA)) test with Tukey's comparisons. ⁽⁴⁾F (ANOVA) test with Tamhane comparisons. Different superscript letters in the same column mean significant difference (P < 0.01).