The of this study was to evaluate the bonding strength of a
posterior composite restorations when two different types of
equipment methods were used for preparation of dentin (Erbium-doped
yttrium aluminum garnet laser (Er:YAG ) and diamond burs).
This study specimen consisted of Eighty molars, was divided
randomly into two main groups (40 molars were prepared with
diamond burs, and 40 molars were prepared with laser Er: YAG).