Effect of acid erosion on enamel bond strength of self-etch adhesives and sonic velocity measurement of enamel

Abstract

The purpose of this study was to investigate the effect of acid erosion on the bonding performance of universal adhesives. Freshly extracted bovine teeth were cut into enamel slabs and assigned to either the Er or the control group. Specimens in the Er group were immersed in citric acid solution (pH 2.1) twice a day and stored in artificial saliva, while control specimens were simply stored in artificial saliva. Differences in the mean values between the control and Er groups were greater than expected, despite accounting for the effect of differences in the adhesive systems (p=0.016). The Er group mainly exhibited cohesive failure in the enamel, while adhesive failure was more frequent in the control group. The sonic velocity was found to decrease over time in the acid attacked specimens. The results indicated that bond strengths of universal adhesive tested increased in eroded enamel.

Resistência da união de restaurações confeccionadas com sistemas adesivos universais em dentes acometidos por erosão ácida

“…Os resultados demostraram que os diferentes sistemas adesivos universais não apresentaram diferenças entre si na adesão dentro de cada substrato testado (esmalte e dentina). Esse resultado pode ser reflexo da erosão dos substratos que torna a superfície mais irregular e porosa, o que desempenha um fator importante no mecanismo de adesão, favorecendo um forte embricamento mecânico (14).…”

“…Em relação aos padrões de fratura em esmalte erodido, houve predomínio da falha coesiva em resina. A erosão neste substrato resulta em aumento da porosidade em sua superfície (14), elevando a molhabilidade e promovendo um melhor embricamento mecânico das resinas compostas (24).…”

Comparative Evaluation of Resin Dentin Interface using Universal and Total- Etch Adhesive Systems on Sound and Eroded Dentin: In Vitro Study

“…The composition of the artificial saliva used in this study were KCl (16.1 mM), NaCl (14.4 mM), K 2 HPO 4 (2.0-mM), MgCl 2 •6H 2 O (0.3 mM), CaCl 2 •2H 2 O (1.0 mM), and sodium carboxymethyl cellulose (0.10 g% ; CMC-Na) at pH of 7.0. 20 Selection of teeth and division of teeth was done by another investigator to avoid the selection bias by the operator.…”

“…This cycle was repeated for five times in 3 days. 20 In the control group, the sound dentin sample teeth were simply incubated in artificial saliva at 37°C for 3 days without exposure to erosive cycle.…”

“…Bond strength of the restoration of eroded dentin are being questioned in day-to-day practice, and only few reports explained the relationship between the bond strength and the restoration especially using universal adhesive system. 20 Thus, there is a paucity of evidence that explains the relationship between total-etch and self-etch technique, especially on eroded dentin using universal adhesive system. Additionally, interfacial microscopic examination of resin dentin interface is conventionally done by using optical microscope and SEM.…”