BOND STRENGTH ON ERODED DENTIN: A PILOT STUDY USING AN ER: YAG LASER

Vivian Colucci, Rodrigo Alexandre Valério, Tiago Gilioli Varise, Taísa Penazzo Lepri, Cecília Pedroso Turssi, *Silmara Aparecida Milori Corona

ABSTRACT

Objectives: The aim of the present in vitro study was to evaluate the effect of an Er:YAG laser on the bond strength of eroded dentin. Materials and Methods: Fifteen bovine incisors (n = 10) were sectioned crowns, resulting in 60 samples (4 x 4 x 2 mm). Samples were randomly assigned in 3 surface treatment: A. 5% fluoride varnish; B. Er:YAG laser irradiation and C. no treatment (control) - and 2 bond systems: (I) Total etching and (II) Self-etching. Specimens were immersed in 0.3% citric acid solution (pH 3.2). The 5% fluoride varnish and an Er:YAG laser (80 mJ, 3 Hz) were applied at dentin surface. After performing the treatments on eroded dentin, specimens were randomly subdivided according to the bond system (I or II). All specimens were individually fixed at a metallic device, forming a cylinder (3 x 4 mm), to be subjected to the shear bond strength test (MPa). Results: ANOVA showed that there was no statistically difference between the employed surface treatments (p < 0.05). With respect to the bond systems, it was observed greater shear bond strength to the self-etching bond system (Adhese – 11.89 MPa) compared to the total-etching (Excite – 8.45 MPa) (p <0.05). Conclusion: It can be concluded that the treatments performed at eroded dentin did not interfere on the bond strength of the composite resin to this tissue. The self-etching adhesive system provided greater adhesion to the eroded dentin, compared to the total-etching.

Keywords: Erosion, Dentin, Lasers, Fluoride varnish, Bond strength.