Bond strength of cemented fiber posts to teeth with simulated internal root resorption

Abstract

Background: Teeth with internal root resorption (IRR) have guarded prognosis, considering that IRR defect could influence on the post bond strength. The aim of this study was to evaluate the bond strength and the bond interface between different glass fiber-reinforced posts (FRP) after cementation in teeth with simulated internal root resorption (IRR). Material and Methods: Forty-five (45) human premolar roots with simulated IRR were embedded in acrylic resin blocks and cross-sectioned into two segments, enabling them to be re-approximated by screws. Intracanal medication was inserted for 15-days, removed by passive ultrasonic irrigation (PUI) and examined by stereomicroscopy. The push-out bond strength of two fiber reinforced composite posts (Rebilda Post -RP) and Rebilda Post GT -GT, (VOCO) were evaluated at the cervical and IRR regions (n = 20). And, the bonded interface between resin cement and root dentine was analysed by scanning electron microscopy (SEM). Results: 62.5% of IRR were not completely cleaned by PUI. Bond strength values at the cervical region (9.8 and 14.6 MPa) were higher than the IRR region (6.3 and 4.2 MPa). Micrographies showed bubbles in the cement and spaces in the bonded interface. Conclusions: RP post showed better bond strength at the cervical region while GT had better bond strength at the IRR region.

Effect of Passive Ultrasonic Irrigation over Organic Tissue of Simulated Internal Root Resorption

“…Ltda, Petrópolis, RJ, Brazil) and irrigated with 3 mL of 1% NaOCl. e roots were embedded in cylinders (3 cm diameter; 2.5 cm height) of self-cured acrylic resin (TDV, Santa Catarina, Brazil), and then an IRR was simulated [24] as shown in Figure 1 and detailed below.…”

Comparison of the effect of QMix and conventional root canal irrigants on push‐out bond strength of fiber post to root dentin

“…In this study, most failure modes were adhesive failure at the resin‐dentin interface which was similar to the results of Elnaghy et al, (Elnaghy, 2014) Bouillaguet et al, (Bouillaguet et al, 2003), and Afkhami et al (Afkhami et al, 2018) However, in this study, similar to that of Abreu et al, the mode of failure in most specimens was adhesive at the resin cement‐dentin interface (Abreu et al, 2020). In the study by Bouillaguet et al, (Bouillaguet et al, 2003) higher frequency of adhesive failure at the resin cement‐root dentin interface was attributed to polymerization stresses in this region, due to the canal geometry.…”

“…Thus, the C‐factor is high in this region, which would generate a high stress due to shrinkage of resin cement against the canal wall, that would compete with the bond strength at the adhesive interface (Carvalho et al, 2020). Moreover, according to Abreu et al (2020), higher frequency of adhesive failure at the resin cement‐root dentin interface is due to chemical compatibility of the resin matrix of fiber post with cement and also adequate wetting of the post with the cement when bonding the fiber post margins.…”