Table 1.

Operative procedure

Adhesive system	Etching	Bonding system	Restoration
All bond 2	35% phosphoric acid–15 seconds Water spray–30 seconds Gentle air drying–20 seconds	Primer applied–30 seconds. gentle blow drying 2 coats of adhesive gentle blow drying,and light–cured	All the prepared specimens were restored with single composite resin. Z100 Composite resin was inserted in increments into the circular hole of the teflon mould and light–cured. The Teflon mould was removed after curing.
Prime and bond NT	35% phosphoric acid–15 seconds Water spray–30 seconds Gentle air drying–20 seconds	2 coats,gentle blow drying and light–cured
Clearfil Liner Bond 2V	Self–etching primer, apply for 30 seconds, do not wash	2 coats of bonding agent and light–cured