Figure 2. Transmission electron micrographs showing the nanoleakage in carbamide-peroxide-bleached, acid-etched enamel that was bonded with Prime&Bond NT. (A) A low-magnification view of the resin-enamel interface. C, resin composite; A, adhesive containing nanofiller particles; E, prismatic enamel. A region with more extensive etching is depicted, although areas with etching effect similar to that in Fig. 1A were commonly observed. (B) A high-magnification view of the resin-enamel interface, showing more extensive silver grain deposition (open arrowheads) within the etched enamel (E) as well as the adhesive layer (A). Additional bubble-like structures with peripheral silver deposits (pointers) were also evident. Arrow: less-electron-dense nanofiller clusters in the adhesive. (C) A high-magnification view showing a dense aggregation of isolated silver grains (open arrowheads) and almost spherical, bubble-like structures with incomplete peripheral silver deposits (pointers) in the adhesive layer. Arrow: nanofiller clusters.