” DOUBLE STEP REVERSE”( DSR): A NEW PROTOCOL IN POLYVINYLSILOXANES( PVS) IMPRESSION- TAKING PROCESS- TWO CASE REPORTS
Figure 12. In this impression the wash material is slightly different from the previous, since it is designed for multiple teeth impression and it has a longer setting time
Figure 13. The finishing line is checked through an optical microscope and probed through endo files. 06
Figure 14. Further evaluation with Fit Checker Blue GC
neath the dies.( Fig. 5) The digital x-rays show that the results are almost completely identical, therefore attesting that both the impressions and the dies are basically very reliable in terms of accuracy. Hence the post-crown, crafted according to the DSR impression, is cemented with a radiopaque resin-based cement and hence an x-ray is taken. Radiographically, we are able to evaluate the equal distribution of the cement all around the post. Once we proceed with the cementation of the
Crown-post, the tooth is ready to be prosthetically prepared and then another DSR impression is taken immediately. With such an accurate impression, the laboratory can craft a definitive ceramic crown with a high grade of precision.( Fig. 6) The two impressions are very similar, as for the accuracy of the models and for the lack of deformation of the post.( Fig. 7) Eventually, thanks to DSR technique, we can easily perform an accurate impression of the root canal in case of a“ post-crown” rehabilitation. This wash
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