” DOUBLE STEP REVERSE ” ( DSR ): A NEW PROTOCOL IN POLYVINYLSILOXANES ( PVS ) IMPRESSION- TAKING PROCESS - TWO CASE REPORTS
Figure 6 . The sequence that leads to the definitive crown
Figure 7 . Before and after the prosthetic procedures
Figure 8 . Teeth 16 and 17 are in need of prosthetic treatments
replacement . ( Fig . 1 ) We removed the metal post by means of an ultrasonic insert and then it is time to take a couple of impressions . The First one is made following the protocol of the “ DSR ” technique : the “ Wash material ” ( Aquasil Ultimate Wash ), after being left for 3 minutes within the root canal , is covered and firmly bonded by the “ Tray material ”. These two materials , after their setting time , are ready to be removed from the arch . The Second impression is made of an eXtra-Light
Viscosity ( Aquasil XLV ) in a monophase technique , where a lentulo is used to push the XLV material deep inside the root canal , gaining more push from the subsequent monophase material , delivered by an impression tray . ( Fig . 2 ) At this time , two dies are made and tagged as “ U ” ( which stands for Ultimate ) and as “ A ”( for Aquasil Monophase ) ( Fig . 3 ); then sent to the laboratory where they make two duralay resin posts according to the plaster models . Through the process of thermocompression , the
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