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I research _ impression and registration master cast. After the impression was taken, the TFD was fixed on the implant abutments using temporary cement (TempBond, Kerr, Orange, CA). It was then left in place until the delivery of the final restoration (Fig. 8c). The new master cast was articulated with the help of the gold copings and the mock-up. The metal framework was milled (here: Titanium Zenotec TI, Wieland, Fig. 9a). The veneering of the superstructure was made using a light-cured indi- rect ceramic polymer (Ceramage, SHOFU, Menlo Park, CA, Figs. 9a–d). The electroformed gold cop- ings were fixed in the metal framework using a self-curingcompomercement(AGCCem,Wieland, Fig. 10). The above-described procedures can be also performed in cases in which a fixed denture was planned for the rehabilitation of the full-arch (Figs. 11a & b, Figs. 12a–c) and in cases where part of the natural dentition is periodontally stable and can be applied as abutments. In these cases, the immediate full denture can be designed as a cover denture. From this cover denture, a DentDu could be fabricated and further used as described above (Figs. 13a–c). Porcelain is a possible material for veneering of fixed-denture frameworks. If the angulation of theimplantsdoesnotallowfortakingimpressions in the above-described way and an open-tray im- pression is preferable, fenestrations can be fabri- cated into the DentDu (Fig. 14). _Discussion The reconstruction of the fully edentulous arch withimplant-retaineddenturesnecessitatesthor- ough planning and a precise and passive fit of the suprastructure. A previous study demonstrated that a passive fit between the implant superstruc- ture and the underlying abutments is essential for the long-term success of the implant prosthesis.5 To achieve a passive fit, an accurate positioning of the implant replicas in the master cast must be as- sured. The impression technique and the splinting of the implant copings are factors which may contribute to errors in the final positioning of the implant analogs, thus leading to inaccuracies in the fit of the final superstructure.5-10 Furthermore, the angulation or proximity of the implants may inhibit proper seating of the impression copings and/orcaps,whichmayalsohaveadetrimentalef- fect on the registration of the implant position.11 The precise recording of the maxillo-mandibu- lar, e.g. interocclusal, relationship is a prerequisite for achieving proper occlusion and a successful treatment outcome.1,10 The initially delivered den- tureallowedforthecorrectionoftheinterocclusal relationship, tooth shape and color and angula- tions during the entire healing period. In this way, the patient was able to acclimatize to the function and esthetics of the denture. In the method de- scribed in this report, an accurate impression and recording of the full denture was achieved by using a duplicate as a custom tray for the impression. Therefore, it was not necessary to repeat all the 30 I CAD/CAM 1_2013 Fig. 6c_Electroformed gold copings. Figs. 7a & b_The customized abutments are mounted on the implants using a transfer key. Fig. 7c_Electroformed gold copings in situ. Figs. 8a & b_Brial of the mock-up. Fig. 8c_Temporary fixed denture in situ. Fig. 8b Fig. 8cFig. 8a Fig. 6c Fig. 7a Fig. 7b Fig. 7c