Bond Strength Evaluation of Two Adhesive Systems in Fiberglass Posts Cementation

Abstract

Objective: To compare the bond strength of three-step and self-etch adhesive systems with and without prior acid etching on bonding of fiberglass posts in root canals. Material and Methods: Experiments were conducted on roots of five upper molars without curvature and sectioned in a cervical-apical direction. With the aid of a highspeed turbine and diamond tips, cylindrical cavities 7 mm in depth and 1.4 mm in diameter were made in the dentine. The roots of the same tooth were used, where the retainers were cemented, thus generating three groups: Group A: Adper Scotchbond Multipurpose Plus (SBMP) + Rely X ARC; Group B: Single Bond Universal (SBU-1) + Rely X ARC, with acid etching prior to adhesive insertion; Group C: Single Bond Universal (SBU-2) + Rely X ARC. The samples were stored in a bacteriological incubator at 37ºC with 100% humidity for 48h and were subsequently cross-sectioned to obtain 3 dentine discs 1mm in thickness. Forty-five specimens were subjected to the push-out test. Results: Through the analysis of variance and Tukey's test, it was found that SBMP showed, with statistical significance (p<0.05), highest bond strength when compared with the SBU-1 and SBU-2 systems. The observed difference in the discs was located in the cervical portion. Conclusion: The three-step adhesive system had higher bond strength with the substrate than the self-etching adhesive only in the disc in the cervical portion; further, statistically, the prior application of phosphoric acid in SBU-1 did not affect its bond strength significantly.

Cimentação de Pinos de Fibra de Vidro: Revisão de Literatura

“…Scelza et al 35 ainda ressaltam que o PFV quando cimentado com cimentos resinosos e sistemas adesivos distribuem as tensões recebidas ao longo da estrutura dentária de forma uniforme diminuindo assim os riscos de fratura. Por outro lado, Magalhães et al 8 citam como desvantagens deste cimento a sensibilidade da técnica e seu alto custo.…”

“…Quanto a resistência de união, os sistemas adesivos convencionais apresentam valores superiores. No estudo realizado por Scelza et al 35 , os autores analisaram dois sistemas adesivos durante a etapa de cimentação de PFVs, compararam a resistência de união entre um adesivo de três etapas clínicas e de sistemas adesivos autocondicionantes, e avaliaram também a influência do condicionamento ácido prévio antes da aplicação de sistema adesivo autocondicionante. Os resultados obtidos do presente estudo demonstraram que o sistema adesivo de três etapas apresentava maior resistência de união quando comparada com os adesivos autocondicionantes.…”