Comparing bond strength of light-cured resin cement with E-max using two protocols of E-max cementation (in-vitro study).

Abstract

Aim of the study: This study aims to compare the effect of application the phosphoric acid protocol with the traditional protocol on the shear bond strength and the micromorphological changes on the ceramic surface.

Materials and Methods: The sample was 21 disks of IPS e.max press . One disk  for SEM and  20 disks for in-vitro study, were selected in 2 groups (n=10): group1: 10% HF for 20s + Silane, group2: 10% HF for 20s + 37% PA for 30s + Silane. The Resin cement (Choice 2) was applied using a 6mm-diameter plastic tube and light cured. After storage in deionized water, The sample was thermocycled for 5000 cycles (5-50)C. Shear test was applied on the sample using a Universal Testing Machine. The peak failure load was used to calculate the shear bond strength, then the failure models were selected. Data were analyzed by one-way ANOVA.

Results: The study showed that the application of PA had increased the value of the shear bond strength , but there was not statistically difference between the two groups.

Conclusion: : Within this study limits, We conclused that the application of phosphoric acid for 30s discards the precipitation of salts, but it was no  statistically difference  on shear bond strength between the ceramic and the used- resin cement.