Figure 1. SEM micrographs of the dentin side of a fractured beam following application of single-bottle total-etch adhesives to oxalate-desensitizer-treated acid-etched dentin. (A) Spherical globules (arrowheads) with sizes ranging from 2 to 4 µm were preferentially found at the orifices of the dentinal tubules in the PB-SS subgroup. Clusters of smaller globules (arrow) were found between the larger globules. Patent dentinal tubules (pointer) were frequently observed. (B) Spherical globules (pointers) up to 12 µm were also observed in the adhesive layer of the PB-BB subgroup. (C) The dentin side of the OB-BB subgroup was covered with a continuous layer of spherical globules with sizes ranging from 0.5 to 3 µm. Patent dentinal tubules (arrowheads) were evident from the dentin (D) below. (D) No spherical globules could be found on the dentin surface of the SB-SS subgroup. Numerous fractured resin tags (arrowheads) could be seen at the base of the hybrid layer (H).