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research _ impression and registration I were taken in centric occlusion with modeling resin (pattern resin®, GC, Alsip, IL; Fig. 1c), using the casts of the original denture. Afterwards, the DentDuwasplacedinanarticulatorandacontrol- ling of the occlusion was made (Fig. 2a) with the bite records. A pickup transfer system consisting ofatitaniumimpressionpostandaplasticimpres- sion sleeve was employed (Dentegris, Duisburg, Germany, Fig. 2b). The DentDu was carefully mod- ified by creating internal clearance in the area of the implants so that it could be applied as an indi- vidualized custom tray. This permitted it to be fully seated when the impression posts were in place. Impressions were generated by a polyether mate- rial (Impregum, 3M ESPE, St. Paul, MI). During this process, the DentDu was kept in centric occlusion using the bite records (Fig. 3a). The titanium impression posts were connected with the implant analogues and with the plastic impression sleeves (Dentegris), which were em- bedded in the impression material (Fig. 3b). A mas- ter cast was then fabricated and articulated with the help of the bite records (Fig. 3c, Figs. 4a & 4b). Customizable abutments (Dentegris) were taken to fabricate the implant abutments. Paral- lelism, angulation, position and shape of the im- plant abutments were determined using a silicon key fabricated from a matrix of C-silicone (Zeta- labor, Zhermack SpA, Badia Polesine, Italy, Fig. 5). Thedentistandthedentaltechnicianreliedontwo alternatives for customized abutments selection: 1) UCLA customizable abutments (UCLA, Dente- gris) for casting with a gold alloy (for example, Portadur P4, Au 68.50%, Wieland, Pforzheim, Germany,Fig.6a)or2)platinum-iridiumcustomiz- able abutments (PTIR, Dentegris) for casting with a chromium cobalt (CrCo) alloy (for example, Ankatit,AnkaGuss,Waldaschaff,Germany,Fig.6b). After casting, the customized implant abut- ments were grinded, polished and served as the basis for the fabrication of electroformed pure- gold copings with a thickness of 0.25 mm (AGC Galvanogold, Au > 99.9%, Wieland, Fig. 6c).2-4 The framework was then constructed via CAD/CAM. To ensure proper functioning of the framework, a plastic mock-up and a temporary fixed denture (TFD) were milled (ZENO-PMMA, Wieland). The customizedimplantabutments,theelectroformed copings, the mock-up and the TFD were deliv- ered by the dental laboratory for the next clinical session. The abutments were transferred, positioned on the implants and torqued to 35 Nm using a resin transfer key (pattern resin, GC; Figs. 7a & b). From thispointon,thecustomizedabutmentsremained fixed in order to avoid any possible inaccuracies. The electroformed copings were placed on the im- plant abutments (Fig. 7c). The mock-up was placed over the electroformed copings and the occlusion was checked with the bite records (Figs. 8a & b). A final impression with a polyether impression material (Impregum, 3M ESPE) was taken with electroformed copings. The mock-up was further set up and used for the fabrication of a new (final) Fig. 3a_Taking the impression with the DentDu. The bite records were used to determine the exact position. Fig. 3b_Fabrication of the master cast. Fig. 3c_Placement of the cast into the articulator using the bite registrations. Fig. 4a_Master cast. Fig. 4b_The master cast is placed into the articulator. Fig. 5_The customized implant abutments are fabricated using a matrix of C-silicone. Fig. 6a_Gold customized abutments. Fig. 6b_Chromium cobalt (CrCo) customized abutments. I 29CAD/CAM 1_2013 Fig. 3a Fig. 3b Fig. 3c Fig. 6a Fig. 6b Fig. 4b Fig. 5 Fig. 4a