A comparison of the shaping ability of three nickel-titanium rotary instruments: a micro-computed tomography study via a contrast radiopaque technique in vitro

Table 3 Different measurement levels of centring ratio values for tested groups (mean ± SD)

Group (n = 10)	Centring ratio (mm from the apex)
Group (n = 10)	1 mm	2 mm	3 mm	5 mm	7 mm
PTU^†	0.76 ± 0.19	0.69 ± 0.17	0.52 ± 0.15	0.79 ± 0.17	0.72 ± 0.11
Reciproc	0.70 ± 0.12	0.54 ± 0.11	0.53 ± 0.15	0.80 ± 0.12	0.84 ± 0.11
K3XF	0.77 ± 0.15	0.82 ± 0.10*	0.81 ± 0.13*	0.86 ± 0.13	0.84 ± 0.13

^†, ProTaper Universal
* Mean values represented with different superscript letters are significantly different according to the Kruskal-Wallis test (P < .05)

ISSN: 1472-6831