Fig. 4: Representative cross section images of fractured dentin samples by SEM in backscattered electron mode: images of the upper row show an overview (scale bar corresponds to 100 µm), whereas images of the lower row depict a detailed view in higher magnification (scale bar corresponds to 20 µm).
From: Dentin tubule occlusion by a 38% silver diamine fluoride gel: an in vitro investigation

a, b Show the experimental formulation (sample A1), (c) and (d) the placebo (sample B3) and (e) and (f) the positive control (sample C1). The samples surface is indicated by arrows.