Effect of air abrasion and erbium-doped yttrium aluminum garnet [er: yag] laser preparation on shear bond strength of composite to dentin

ABSTRACT

The aim of this study was to assess shear bond strength of composite to dentin after air abrasion and laser treatment. 40 human extracted molars divided into 4 groups [n=10] received the following treatments. Group 1 carbide bur, Group 2 air abrasion with aluminum oxide 50 microm, Group 3 irradiated with Erbium-Doped Yttrium Aluminum Garnet [Er YAG] laser [150 mJ/20Hz], Group 4 irradiated with Er YAG laser [150 mJ/20Hz]+ air. Specimens in all groups were chemically etched with phosphoric acid 37% and treated with bonding agent [single bond 3M]. Then, composite build-up was performed by tygon tube. After storage in distilled water at 37°C for one week, all specimens were subjected to a shear bond strength test with universal testing machine. Data were analyzed with ANOVA and T-Test. The mean and standard deviation of shear bond strength of the 4 groups were 20.8 +/- 6.76, 14.98 +/- 3.98, 11.43 +/- 4.36 and 14.95 +/- 3.18 MPa, respectively. Air abrasion after laser treatment improved the shear bond strength