Influence of time and medium of storage on the bond strength and microleakage of adhesive systems

Abstract

Objective: the aim of this study was to evaluate the influence of time and medium of storage in the tensile strength of two adhesive systems after different periods of storage. Material and Methods: eighty bovine incisors were selected and randomly divided into eight groups (n = 10) according to the adhesive system, which are as follows: Adper Scotchbond Multi-Purpose (ASBMP) and Clearfil SE Bond (CLSEB), medium of storage [water (A) or demineralization / remineralization solution (DES/RE)] and time of storage (7 or 30 days). After storage, the samples were subjected to mechanical testing to analyze, “in vitro,” the bond strength (BS). The nanoleakage of the hybrid layer was evaluated using scanning electron microscopy (SEM), and its constituents have been assessed by energy-dispersive X-ray spectroscopy (EDS) microanalysis. The BS values were statistically analyzed using ANOVA (p < 0.05). Results: the BS values of ASBMP were A7 days: 14.86 ± 5.64; A30 days: 13.60 ± 3.57; DES/RE7 days: 13.60 ± 3.57; DES/RE30 days: 13.24 ± 4.19. For CLSEB the values obtained were A7 days: 13.16 ± 5.26; A30 days: 6.55 ± 1.82; DES/RE7days: 10.27 ± 3.87; DES/RE30days: 8.42 ± 1.69. Conclusion: it was concluded that the use of the DES/RE solution associated with the immersion of specimens in aqueous 0.05% NaF was favorable for the longevity and integrity of a hybrid layer over time.