Click on image to view larger version.
Figure 2. Optical micrographs illustrating damage sustained in d.SIGN porcelain layers (both translucent and opaque) fused to metal copings, cement-bonded to dental composite support (Z100) following P = 200 N cyclic loading with a sphere indenter (r = 3.18 mm) in water. Specimens were sectioned through the indentation site and polished for cross-sectional examination. d.SIGN porcelains on gold alloy coping after (a) n = 15,000, and (b) n = 25,000. d.SIGN porcelains on palladium-silver alloy coping following (c) n = 50,000, and (d) n = 400,000. Note inner cone cracks (I) and radial cracks (R).
