Evaluation of porcelain surface treatments and agents for composite to porcelain repair

The purpose of this study was to investigate the effects of Nd:YAG laser, air abrasion and acid-etching on the porcelain surface and repairment. Ten standard cylindrical specimens were made for each preparation (Finesse(TM) Dentsply). The specimens were lased for five seconds at a fluence of 80 mJ and a frequency of 20 Hz; air abraded for five seconds with 50 micron Al-oxide (Lit 60 psi); and acid etched with % 9,6 hydrofluoric acid for 120 seconds. The specimens were examined in the scanning electron microscopy (SEM) before and after the Nd:YAG laser, air abrasive and acid-etching. After silane coupling agent was applicated, two flowable restorative materials (Admira Flow(TM), Voco; Tetric Flow(TM), Vivadent) were bonded to the porcelain surfaces. Each group was stored in distilled water at 37degreesC for one day before the determination of shear bond strengths. A shear bond strength machine with 50 kg load cell and a 0.5 mm/min crosshead speed was used. The results were analyzed statistically. There was a significance between the shear bond strenth values of Admira Flow(TM) and Tetric Flow(TM) in the lased group (p