Ecusit-treated dentin surface revealed deposits of small particles on the dense dentin bonding layer (5000x, dotted line: 5 μm). Figure 2h: Prompt-treated dentin surface revealed relatively large porosities on some areas of the dentin bonding layer (55x, dotted line: 200 μm). The dentin surrounding the porosities was covered by a dentin-bonding layer and the dentin hydroxyapatite became indistinct (2500x, the dotted line: 10 μm).