Fig. 5

SEM micrographs taken at × 500 and × 10,000 magnifications. An EDS elemental distribution map and a spectrum of representative points pertaining to the three failed implants can be seen. In case 1, the integrated bone on the upper region of the implant presented an irregular structure (0101-B, blue arrowheads). The presence of organic material was observed on the × 10,000 magnification image (0101-B, white arrows) and was confirmed on the elemental distribution map. The implant surface at the root between two threads had an irregular morphology of a sandblasted and acid-etched surface with signs of oxidation. Some micro-fissures were observed (0102-U, white arrow). A sample of bone graft material was examined at 0103-G. The SEM image revealed an irregular bone structure within the sampled grafting material particles (0103-G, blue arrowheads). The Ca signal at this region was high (23.03%); however, there was no detection of P. High levels of N and O suggested that this was calcified organic material. In case 2, “distant” osseointegration was observed (0204-U, blue arrowheads). EDS analysis performed at the upper region (0204-U) revealed a noticeably high level of Au. At the top of the middle thread, a heterogeneous surface with micro-fissures was observed (0205-M, white asterisks). A thin bone layer and organic matter were observed and confirmed on the distribution map. The Zr signal was detected to have the same distribution as the Ti signal. In the thread top of the apical region (0206-A), even though the EDS result suggested rich Ti content, the SEM image of the surface indicated an irregular morphology with fibers and micro-debris. Au was detected at a noticeable level in this region. In case 3, the fixture surface in the apical region (0307-A) was covered with fibers and heterogeneous organic matter. There was no Ca signal and a very high Au signal in this region