EFEITO DE CIMENTOS ENDODÔNTICOS NA RESISTÊNCIA DE UNIÃO DE PINOS DE FIBRA DE VIDRO À DENTINA RADICULAR

Abstract

The purpose of this study was to evaluate the influence of root canal sealers on the bond strength (BS) of glass fiber posts to root dentin using two cementation systems, two storage periods and the different root regions. It was used 56 human teeth,healthy canines, transversely sectioned immediately after the cement-enamel junction. Then the roots were divided into two groups (n = 28) according to the sealer (with or without eugenol [Endofill and Sealer 26, respectively]). Subsequently, the roots were subdivided into two subgroups each (n = 14) according to the period of storage before the adhesive cementation, 7 and 180 days. Each subgroup was further again subdivided according to the resin cement to be used, being a conventional dual resin cement (Variolink® II ) and a dual adhesive system (Excite DSC), and the other a dual resin cement autoconditioning and self-adhesive (RelyX™ U100). The glass fiber posts (White Post DC) were cemented according to manufacturer's instructions for each cementation system. All roots were stored for one week after adhesive cementation, and were subsequently sectioned transversely into six discs about 1 mm thick each, and the coronal (CT), middle (MT) and apical (AT) thirds of the root canal identified. The push-out test was carried out at a crosshead speed of 0.5 mm/min. The data were statistically analyzed by ANOVA factorial and post-hoc Tukey`s test (p=0.05). The analysis of variance showed a statistically significant effect for the factors time (F=6.58, p=0.01) and root third (F=26.67, p=0.0005). The specimens that received intra-canal posts 6 months after the endodontic treatment had higher BS than the specimens treated 7 days after endodontic treatment. The AT showed statistically lower BS than those of CT and MT. It can be concluded that the bond strength of fiber posts to root dentin was not affected by the root canal sealers and cementation systems.