Group A

37% of phosphoric acid + primer + bonding immediately (negative control)

Group B

Self-etching primer + bonding immediately (positive control)

Group C

Gel 1 + primer + bonding immediately

Group D

Gel 2 + primer + bonding immediately

Group E

Gel 3 + primer + bonding immediately

Group F

Gel 4 + primer + bonding immediately

Group K

Gel 5 + primer + bonding immediately

Group L

Gel 6 + primer + bonding immediately

Group M

Gel 7 + primer + bonding immediately