Effect of dentin pretreatment with potassium oxalate: Analysis of microtensile bond strengths and morphologic aspects

Abstract

An effective and stable bond is the most desirable characteristic of contemporary adhesive systems. The aim of this study was to evaluate the effect of potassium oxalate on dentin/resin bond strength. Dentin on the occlusal surface of human premolars was exposed and etched with 35% phosphoric acid, to receive 3% monohydrated potassium oxalate and the following adhesive systems: Scotchbond Multipurpose (SMO; 3M/ESPE) and Prime & Bond NT (PBO; Dentsply), followed by the application of resin composite (Z250; 3M/ESPE). The control groups (SM and PB) did not receive potassium oxalate application. The prepared teeth were kept in distilled water at 37°C for 24 h and 12 months. They were then cut longitudinally into sticks with a bond area of ∼0.8 mm(2) for submission to the microtensile bond strength test. The data were analyzed by two-factor ANOVA, Tamhane's paired comparisons, and the Student t-test (α = 0.05). The hybrid layer formed was observed by scanning electron microscopy (SEM). SEM analysis of the surfaces treated with PB revealed shorter resin tags associated with the application of potassium oxalate, whereas SM showed tags similar to those without potassium oxalate. A significant difference was shown between the two storage times for each of the protocols. There was a significant difference among SMO, SM, and PBO (24 h), as well as among SM, SMO, and PBO, and between PB and PBO (12 months). The application of potassium oxalate before conventional adhesive systems may result in alteration of the bond strength between dentin and resin composite, depending on the material.

Effect of dentin pretreatment with potassium oxalate: A 6‐year follow‐up

“…De Moraes Porto et al (), using the same methodology of dentin surface treatment, concluded that the bond strength values after storage for 24 h were higher than those observed after 1 year. The application of potassium oxalate on dentin after etching, followed by application of the adhesive does not interfere with adhesive infiltration in a demineralized collagen matrix.…”

“…Studies have suggested the use of oxalate for treatment of dentinal sensitivity in 40% of cases (Cunha-Cruz et al, 2010;Pashley & Galloway, 1985;Pereira et al, 2005;Vieira et al, 2009). Furthermore, oxalate-based desensitizing agents are also being studied in laboratory research as an alternative to be added in restorative procedures with the additional effect of improving resin-dentin bonding over time (Cunha-Cruz et al, 2010;De Moraes Porto, De Andrade, Alves, & Braz, 2012). However, the longevity of this bonding must be evaluated in long-term trials.…”

Nanocomposites: A mini review on their periodontal applications

“…Use of extravagant orthodontic compel may achieve loss of dock and root desorption. In a survey circulated by Katz, an abatement in granulating has been represented by covering the orthodontic wires with inorganic fullerenes-like tungsten disulfi de nanoparticles (IF-WS2) which are known for their astounding oil properties therefore updating the suffi ciency of sliding mechanics (Thompson et al, 2012& De Moraes Porto et al, 2012& Dundar et al, 2011Ouyang et al, 2011.…”

Effect of desensitizing agents on the microtensile bond strength of two‐step etch‐and‐rinse adhesives to dentin

“…Some studies have reported that the bond strength to dentin is reduced after treatment with oxalate‐containing desensitizing agents as a result of poor infiltration of the resin caused by the presence of calcium oxalate precipitates in the dentin sub‐surface . On the other hand, other studies , showed that the presence of potassium oxalate crystals did not reduce dentin bond strength and stated that the occlusive potential of oxalates could facilitate the formation of a more stable and homogeneous hybrid layer owing to the obstruction of tubular fluid that could hinder the hydrolytic degradation of the adhesive interface.…”