Influence of Prolonged Dental Bleaching on the Adhesive Bond Strength to Enamel Surfaces

Abstract

The objective of this in vitro study was to assess the influence of prolonged bleaching pre- and postrestoration on the bond strength (microshear) to enamel using 4% hydrogen peroxide (PH4). In the postrestorative bleached specimens evaluation, the composite cylinders were assembled after bleaching, while in the prebleached specimens, the cylinders were assembled before. Therefore, in the postbleached specimens, 60 bovine teeth were randomly assigned as follows: G1: control; G2: 14 days bleaching before bond strength (BS) testing; G3: 21 days; and G4: 28 days. In prebleached specimens, 180 bovine teeth were randomly assigned as follows: G1: control; G5: 14 days bleaching, storage in artificial saliva (AS) for 24 h before BS testing; G6: 14 days beaching, AS storage for 7 days before BS testing; G7: 21 days bleaching, AS storage for 24 h before BS testing; G8: 21 days bleaching, AS storage for 7 days before BS testing; G9: 28 days bleaching, AS storage for 24 hours before BS testing; and G10 : 28 days bleaching, AS storage for 7 days before BS testing. The results were submitted to ANOVA one-way (postrestoration bleaching) and two-way (prerestoration bleaching) and Tukey’s post hoc test (p≤0.05). In the postrestoration bleaching, no statistical difference between times was found. However, when bleached groups were compared to the control (G1), an expressive difference was detected (p≤0.0001). For prerestoration bleaching, all experimental groups were statistically different from G1 (p≤0.05), except G6 (p≥0.01), and for G5 and G6, statistical differences were found (p≤0.01). There were no significant differences between G7 and G8 and between G9 and G10, regardless of the AS storage times (p≥0.05). It was concluded that prolonged bleaching with PH4 decreased adhesion resistance regardless of the moment of the bleaching (post- and prerestoration bleaching).

<p>Assessing Tensile Bond Strength Between Denture Teeth and Nano-Zirconia Impregnated PMMA Denture Base</p>

“…Studies have shown that bond strength between acrylic teeth and denture base resins could be affected by aging processes such as thermocycling procedure, which could decrease the overall bond strength. 40 , 41 Baia et al 42 concluded that prolonged bleaching either post- and pre-restoration using 4% hydrogen peroxide decreased tooth bonding. However, in another study, decreased bond strength was found in teeth bonded to CAD/CAM and 3D printed denture base resins, when compared to the heat cured acrylic resin, with no significant influence following aging.…”

Effect of disinfection on shear bond strength between heat activated acrylic resin denture base and commercially available denture teeth: An in vitro study

“…Disinfectant solution promote reduction in hardness of denture base resin [40] . Baia et al 2020 [61] observed that prolonged immersion in 4% hydrogen peroxide decreased tooth bonding with the denture base. Clinically, the most important stress factors leading to bond failure were the shear stress.…”

The Potential of Trigona spp. Propolis as an Antioxidant Agent to Reduce Residual Peroxide after Intra-Coronal Bleaching Treatments

“…The oxidation reactions of peroxides produce gaseous bubbles under the enamel surface. The oxygen-containing surface layer that inhibits the polymerization of bonding agents affects the strength of enamel-resin bonds [6,10,17,18]. Various studies suggest suspending the restoration procedure for 2-4 weeks to prevent bond failure between enamel and composite restorations [18].…”

“…The oxygen-containing surface layer that inhibits the polymerization of bonding agents affects the strength of enamel-resin bonds [6,10,17,18]. Various studies suggest suspending the restoration procedure for 2-4 weeks to prevent bond failure between enamel and composite restorations [18]. However, this poses a clinical problem when the tooth should be immediately restored with a composite restoration.…”