The effect of cyclic loading on shear bond strength of fiber post to human root dentin using different adhesive systems and resin cements

Abstract

The purpose of this study was to evaluate the effect of cyclic loading on shear bond strength and microleakage between fibre reinforced post and root canal dentin using various luting cements. Eighty extracted maxillary central incisors and maxillary canines were used. Teeth were decoronated and endodontically treated. Post space of 11 mm was prepared. Samples were divided into 8 groups (n=10) according to the luting cements used (Superbond C&B, Panavia F 2.0, Maxcem Elite and Rely X Unicem) and with and without cyclic loading. D.T.Light post#3 was luted into the prepared post space following the manufacturer’s recommendation, 20 teeth for each luting cements. After that 10 teeth of each luting cements (40 specimens) were submitted under cyclic loading; 1X106 cycles. All specimens were serially sliced into three 1.5-mm-thick slabs for the push out test. After that each teeth were cut from the apex 5 mm then the middle portion specimen with 5 mm height was evaluated. Methylene blue solution was used for dye penetration. Dye penetration distance was evaluated by measuring the distance using stereomicroscope at 25X magnification and Pixera software. Two-way analysis of variance (ANOVA) revealed that only different luting cements affected the push out bond strength. Superbond C&B provided the highest bond strength while Maxcem Elite provided the lowest bond strength. For microleakage, two-way analysis of variance (ANOVA) revealed that both the type of luting cements and the cyclic loading significantly affected microleakage of fibre reinforced post bonded to root canal dentin. The microleakage only in Panavia F 2.0 groups with cyclic loading were significantly higher than Panavia F 2.0 groups without cyclic loading.