Table 2. Frequency of the shapes of canal orifices in Mandibular first molars.

	Mandibular first molar (n = 1,067)
	Mesial	Distal
Orifice shape	Mesio-buccal and Mesio-lingual	Disto-buccal and Disto-lingual	Distal
Round	55.4%	57.8%	11.7%
Oval	44.6%	42.2%	84.2%
Others	–	–	4.1%
df	2	2	3
Chi square value	12.82	292.91	727.08
p value	0.01*	0.01*	0.01*

Notes:

Test applied: Chi-square test.

^*p ≤ 0.05 statistically significant.