Figure 2.

Transmission electron microscopy images showing interfacial nanoleakage expression. D, dentin; HL, hybrid layer; C, composite resin. Original magnification: 4600×. Adhesive interfaces created by XP Bond after riboflavin/UVA treatment (Figs. 2a, 2c, 2e) or on control (Figs. 2b, 2d, 2f), respectively. Scattered deposits of silver nitrate were found immediately after bonding on riboflavin/UVA-treated specimens (T₀, Fig. 2a) and on control specimens (T₀, Fig. 2b). After 6 mos of storage in artificial saliva at 37°C, both the riboflavin/UVA-treated interface (T₆, Fig. 2c) and the control specimens (T₆, Fig. 2d) showed similar silver deposits with increased nanoleakage compared with T₀. After 12 mos of storage, silver deposits were recorded in the riboflavin/UVA-treated group (T₁₂, Fig. 2e), and large areas of silver diffused throughout the hybrid layer were frequently found in controls (T₁₂, Fig. 2f).