Fig. 2.
SEM microphotographs of representative fractured beams of the dentin side (200 × , image on the left) and details of the bonded surface (500 × , image on the right) of RelyX Ultimate (RXU) and Variolink EstheticDC (VAR) in the self-cure (SC) and dual-cure (DC) mode, after 12 months of laboratory aging (T12). A–B RXU SC and DC, respectively; C–D VAR SC and DC, respectively. Mixed adhesive/cohesive failure pattern was predominant in all tested groups. Rough surface with porous agglomerates were noticed, probably related to areas of suboptimal polymerization producing irregularities at the cement/dentin interfaces (white arrows). These sites may expedite premature restoration debonding