Effect of Oxalate Desensitizer on the Durability of Resin-Bonded Interfaces

Abstract

Clinical RelevanceDespite oxalate desensitizer showing a decrease in the rate of resin-dentin bond degradation over time, it compromised the baseline bond strength of etch-and-rinse adhesives to dentin. Further investigation regarding reliability of the combination of oxalate desensitizers and etch-and-rinse adhesives is required prior to implementation of this approach in the clinical routine. SUMMARYPotassium oxalate desensitizers were previously shown to effectively reduce the immediate permeability of resin-bonded dentin. The current study evaluated whether the effect of the combined application of oxalate with etch-and-rinse adhesives interferes with the durability of resindentin bonds when using etch-and-rinse adhesives. The bond strength of resin-bonded dentin specimens composed of two-step or three-step etch-and-rinse adhesives (Single Bond, One-Step and Scotchbond Multi-Purpose, respectively) BISCO, Inc). The treatment of dentin with potassium oxalate was shown to negatively affect the baseline bond strength of resin-bonded dentin specimens, regardless of the adhesive used (p<0.05). After storage, the bond strength of the resin-bonded interfaces was significantly reduced for all the tested groups (p<0.001). Nevertheless, the rate of decreasing bond strength was significantly lower for oxalatetreated specimens than for the controls (p<0.05).

Four-year randomized clinical trial of oxalic acid pretreatment in restorations of non-carious cervical lesions

“…After 2 years, they also showed that the potassium oxalate may adversely affect the baseline hardness of etch-and-rinse adhesives [34]. Therefore, in accordance with these previous studies [21,[29][30][31][32][33][34], it can speculate that crystal precipitation on the etched dentin surface impaired the adequate hybrid layer formation.…”

“…Silva et al [21] also evaluated whether the effect of the combined application of oxalate with etch-and-rinse adhesives interferes with the durability of resin-dentin bonds when using two-and three-step etch-and-rinse adhesives. They used the microtensile method in the laboratory and showed that, despite oxalate desensitizer being shown to contribute to the reduction of resin-dentin bond degradation over time, it compromised the baseline bond strength to the teeth that received potassium oxalate after acid etching.…”

“…Silva et al [21] also concluded that potassium oxalate played an important role in decelerating the long-term degradation of the resin-dentin bonds. They argue that the presence of calcium oxalate crystals partially blocking the fluid transudation improves the resin-dentin bond strength due to the decreased dilution of the adhesive by dentin fluids, mainly in deep dentin.…”

“…When applied on acid-etched dentin, calcium oxalate crystals tend to form only in the dentin tubules, leaving the dentin surface unobstructed and available for bonding with dental adhesives [21,22]. The use of oxalate during bonding procedures could enhance solvent evaporation by decreasing the amount of water entrapped within these adhesives, allowing for better control of the adequate wet and facilitating the penetration of adhesives into wet demineralized dentin [14,22,23].…”

Effect of oxalic acid pre-treatment in restorations of non-carious cervical lesions: A randomized clinical trial

“…[10] However, it was observed a reduction in the bond strength to the teeth that received oxalic acid after aging. [11]…”