Bond Strength After Er:YAG Laser Preparation in Permanent Teeth

Objectives: The purpose of this “in vitro” study was to evaluate the influence of Er:YAG laser preparation on shear bond strength of two different adhesive systems to dentin. Methods: Forty buccal surfaces of molars were embedded in acrylic resin, and grounded with water sandpapers to obtain a flat surface. The adhesive systems used were: Single Bond (3M/Espe) e Adper Prompt (3M/Espe). Specimens were randomly divided into 4 Groups (n=10), according to the superficial preparation and adhesive systems: I-A: 37% phosphoric acid gel + SB; II-A: AP; I-B: Er:YAG (300mJ, 2 Hz) laser preparation + 37% phosphoric acid gel +SB e, II-B: Er:YAG (300mJ, 2 Hz) preparation laser + AP. The composite resin employed was FiltekTM Supreme (3M). The shear bond strength tests were performed using a Universal Testing Machine (50 kgf; 0.5 mm/min). Failure mode was assessed using a X40 magnification stereomicroscope. Data were submitted to statistical analysis by ANOVA and Mann Withney test. Results: The means (MPa) were: I-A: 19.23(±7.62); II-A: 7.31(±2.59); I-B: 6.99(±1.99) e II-B: 4.32 (±2.00). It was observed statistically significant difference (p<0.05) between the tested adhesive systems, as well as for the superficial preparations. The highest values were presented by Single Bond and phosphoric acid application. Conclusion: It may be concluded that Er:YAG laser preparation negatively influenced the adhesive resistance of the employed systems, being more evident for Single Bond.