Fig. 2.

Scanning electron micrographs of xenon plasma focussed ion beam (Xe PFIB-SEM) milling of tooth surface to create a cross-section of dentine tubules. A. Manipulator needle attached to a single crystal silicon mask (100 µm × 50 µm × 50 µm) held over the surface of a polished tooth slice to mill a flat surface using focussed xenon ions. B. Figure ‘a’ magnified to show the surface of the tooth and the cross-section after removal of the mask. C. The surface of the dentine from a tooth slice before embedding and polishing. D. The ‘top’ surface view of the polished tooth after milling. E. The ‘top’ surface of the polished surface after milling at the edge of the mask. The left hand side of this micrograph shows the pillaring effect from the xenon beam if a mask is not used. Scale bars = A. 100 µm, B. 20 µm, C-E. 5 µm.