Table 2: Intragroup comparison between 5th and 7th generation bonding agents (using unpaired t test)

Group		Mean (MPa)	S.D.	T value	p value
I	5th generation	20.65	1.03	18.927
	7th generation	13.07	0.74
II	5th generation	12.02	1.29	10.162	< 0.001
	7th generation	7.13	0.82
III	5th generation	15.04	1.12	10.188
	7th generation	8.43	1.72
IV	5th generation	22.91	3.70	8.646
	7th generation	11.60	1.85