Effect of different adhesion strategies on fiber post cementation: Push-out test and scanning electron microscopy analysis

Abstract

Aim:The aim of this study was to investigate the effect of phosphoric acid etching and the dentin pre-treatment with sodium hypochlorite (NaOCl) on the push-out bond strength between fiber post and root canal dentin.Materials and Methods:Root canals of 48 human incisors were selected, post spaces were prepared and assigned to four groups: G1-37% phosphoric acid (15 s); G2-5.25% NaOCl (2 min) +37% phosphoric acid (15 s); G3-37% phosphoric acid (60 s); and G4-5.25% NaOCl (2 min) +37% phosphoric acid (60 s). Fiber post cementation was performed with two-step etch-and-rinse adhesive system/dual-cured resin cement according to the manufacturer's recommendation. After 24 h, each root was sectioned transversally into three slices (cervical, middle and apical) and the bond strength of each section was determined using a push-out bond strength test. Morphology analysis of the bonded interface was evaluated using a scanning electron microscopy. Push-out strength data (MPa) were analyzed by Analysis of Variance and Tukey-Kramer (α = 0.05).Results:Considering the NaOCl pre-treatment, no statistically significant differences were observed among groups; however, when the phosphoric acid was applied during 60 s in the apical portion without NaOCl pre-treatment, the bond strength was statistically significant increased.Conclusion:The NaOCl pre-treatment did not improve the bond strength of adhesive luting cement to root canal dentin. The findings suggest that the use of 37% phosphoric acid for 60 s may have a beneficial effect on bond strength in the apical root third.

Evaluation of the effect of chlorhexidine and sodium hypochlorite in adhesive cementation of fiber posts - in vitro study

“…In the present study, no improvement in the BS was found for the groups treated with NaOCl, which is similar to the findings by Saraiva et al 20 and Lindblad et al 21 . Those studies also found no improvement in the results of adhesive BS in root canals.…”

“…In order to reduce intraradicular pin displacement failures and to prolong the longevity of teeth restored with this apparatus, studies are conducted to investigate the performance of different dental substrate treatments in order to obtain greater durability and efficacy of the adhesive interface [18][19][20] . Studies have investigated the action of CHX 19,[21][22][23] and NaOCl 24 on root dentin, in order to maintain the integrity of the hybrid layer.…”

Impact of different surface treatment methods on bond strength between fiber post and composite core material

“…The bond strength in the current study was investigated using a push-out testing method, which has been reported to apply a shear stress parallel to the FP and CC interface that is comparable to the clinical situation ( Bitter et al, 2007 , Saraiva et al, 2013 , Santos et al, 2017 ). Furthermore, the recorded push-out bond strength values revealed limited variability which indicated high reproducibility of the measurements using the push-out testing method ( Goracci et al, 2004 , Goracci et al, 2007 , Arslan et al, 2016 ).…”

Quantitative Analysis of Defects at the Dentin-Post Space in Endodontically Treated Teeth

“…The lack of the etching gel could bring about the persistence of an oxygen-rich layer in the post space apical dentin. However, the use of 37% of phosphoric acid for 60 s increased the bond strength in the apical third of the root dentin [ 69 ].…”