Table 1.

Mean surface area (mm²) and standard deviation of mesiobuccal canal

	Before instrumentation									After instrumentation							Absolute change
	Coronal third			Middle third			Apical third			Coronal third		Middle third			Apical third		Coronal third		Middle third		Apical third
n = 12	Mean		SD	Mean		SD	Mean		SD	Mean	SD	Mean	SD		Mean	SD	Mean	SD	Mean	SD	Mean	SD
Group A	0.523		0.080	0.346		0.051	0.090		0.013	1.030	0.146	0.505	0.074		0.187	0.043	0.507	0.068	0.160	0.023	0.097	0.027
Group B	0.493		0.158	0.317		0.092	0.097		0.046	1.293	0.254	0.597	0.161		0.202	0.095	0.800	0.134	0.280	0.069	0.105	0.052
Group C	0.505		0.142	0.316		0.073	0.103		0.009	1.348	0.296	0.594	0.131		0.210	0.025	0.843	0.169	0.278	0.058	0.107	0.017
ANOVA test applied														F			3.655		19.532		1.025
														p			0.037 (S)		0.00 (S)		0.081 (NS)

p < 0.05 = Significant (S = significant; NS = nonsignificant)