Influence of chlorhexidine on longitudinal bond strength to dentin: in vitro study

Abstract

<p><strong>Objective</strong>: This study evaluated the effect of 0.2% chlorhexidine gluconate solution used as an therapeutic primer on the long-term bond strength of etch-and-rinse adhesive to dentin. <strong>Material</strong> <strong>and</strong> <strong>Methods</strong>: Bovine incisors were worn to expose an area of dentin and were divided into 2 groups: Group C (Control) - acid etching with 37% phosphoric acid + Single Bond; Group CHX (0.2% CHX) - acid etching with 37% phosphoric acid + 0.2% CHX for 30 s + Single Bond. Blocks of composite were fabricated and stored for 24 h or 6 months, sectioned into beams and submitted to microtensile tests. Results were analyzed by two-way ANOVA and Tukey tests. <strong>Results</strong>: Mean (±SD) values (in MPa) were as follow: Group CHX/24h - 41.8(±2.62)A; Group C/24h - 40.8(±3.35)AB; Group CHX/6 months – 36.4(±3.52)B; Group CHX/6 months - 26.1(±1.54)C. <strong>Conclusion</strong>: CHX improve the imediatte bond strength of resin-dentin and significantly lowered the loss of bond strength after 6 months water storage as seen in the control bonds.</p><p><strong>Keywords</strong></p><p>Tensile bond strength; Dentin; Total-etch adhesives; Chlorhexidine gluconate.</p>

Effect of 2% Chlorhexidine Following Acid Etching on Microtensile Bond Strength of Resin Restorations: A Meta-Analysis

“…In the meta-analysis of the 6-month subgroup, a statistical significance was observed indicating an increase of 5.02 MPa in the microtensile bonding strength in the chlorhexidine group compared to the control group. This increase in adhesion strength after 6 months was also corroborated by a recent study in 2017 despite the fact that chlorhexidine concentration was lower than 2% [49].…”

“…At concentrations of 0.05% or 0.2%, there is a certain degree of inhibitory effect of MMPs [6,36,48,49]; however, a clear relationship between the concentration of chlorhexidine and the increase in the bonding strength of dentin-resin bonds has not been demonstrated [44].…”

“…With the passage of time, the hybrid layer gets unstructured due to the activation and bonding of the MMPs in those areas of exposed dentine without infiltrating monomers [20]; however, if previously treated with chlorhexidine, the dentin remineralizes thanks to its cationic properties [49,55]. MMPs are only inhibited when chlorhexidine remains trapped in the dentinal matrix by 2-hydroxyethyl methacrylate (HEMA) [29,56,57].…”

“…MMPs are only inhibited when chlorhexidine remains trapped in the dentinal matrix by 2-hydroxyethyl methacrylate (HEMA) [29,56,57]. When inhibited, the union of the MMPs to the non-infiltrated collagen fibers is avoided [15,49] increasing their action as time passes.…”

Mechanical-physicochemical properties and biocompatibility of catechin-incorporated adhesive resins

“…Next, they were immersed in hexamethyldisilazane (Fluka) in a gas exhaust hood for 10 min. They were then placed on a filter paper under a glass bell for 30 min at room temperature to complete the dehydration process 8 , 22 . Finally, samples were mounted on aluminum stubs and examined using SEM ProX (Phenom World, Eindhoven, Noord-Brabant, Netherlands) under low vacuum and at 2000× magnification.…”