Shear bond strength of direct composite repairs in indirect composite systems.

Indirect composite restorations may require repair during clinical service. This study evaluated the shear bond strength of direct composite repairs in indirect composites after four surface treatment procedures. Cylinders of three indirect composites (n = 10 per group) received the following surface treatment: sandpaper finishing (control group), 50 microm aluminum oxide sandblasting, 50 microm aluminum oxide sandblasting (plus 10% fluoridric acid etching), and 30 microm silaned silicon sandblasting.