Table 1.

Comparison of the average difference in three methods of radiography with and without file

Usage of file	Method of radiography (N)	Mean(SD) of Length	Difference between methods and the golden standard level
With File	Conventional (50)	20.35(1.75)	0.64±0.63
	Digital (50)	20.58(1.69)	0.79±0.78
	Self-developing (50)	20.47(1.83)	0.59±0.59
Without file	Conventional (50)	20.35(1.74)	0.89±0.93
	Digital (50)	20.59(1.69)	0.86±0.95
	Self-developing (50)	20.49(1.84)	0.83±0.90
Total	Conventional (100)	20.47(1.75)	0.64±0.63
	Digital (100)	20.48(1.75)	0.79±0.78
	Self-developing (100)	20.47(1.75)	0.59±0.59