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industry report _ full arch rehabilitation I wax or by reducing it with a bur. Prior to its being sprayed and digitally scanned, the space between the resin bar and the ridge area between the pencil lines on the model is filled with a putty material, so thatthemilledframeworkcanbeincontactwiththe soft tissue of the edentulous ridge (Fig. 6). After the model with the milled abutments and the resin bar were separately sprayed and scanned, the Trinia fiber resin bar was digitally designed on the computer with a minimum thickness of 7.0 mm throughout,anabutmentclearanceof30micronsfor cementandwithamaximumcantileverextensionof 21.0 mm. If necessary, the milled Trinia framework may have been judiciously reduced manually. After cleaning the milled Trinia framework with alcohol, it was placed onto the milled abutments to evaluate and, if necessary, modify the marginal adaptation of the framework to the abutments and to the alveolar ridge of the model. The ridge side of the framework should be convex without any con- cavities.Additionally,theTriniaframeworkwasused to confirm both the path of insertion of the pros- thesis and the sequence of insertion of the milled abutments on the model. After the sequence and path of insertion were confirmed, the facial, oc- clusal and lingual masks were repositioned on the model and attached together with cyanoacrylate glue (Fig. 7). A thin mix of denture resin was poured into the silicone flask through the anterior cutaway or aper- ture in the lingual mask. Final polymerization was achievedwhilethesiliconeflaskandmodelswereun- der hot water, with an air pressure of 3 bars. After polymerization, the Trinia prosthesis was removed from its silicone flask, then finished and polished in a conventional manner. Clinically, after the removal of the temporary abutments from the implant wells, at least two milled abutments were incompletely in- sertedintotheprosthesis.Ifnecessary,theyweresta- bilized with an application of Vaseline, prior to their beingtransportedtothemouthandinsertedintothe well of their implant (Fig. 8). The loosely fitting abut- ment facilitated its insertion into the well of the im- plant(Fig.9).Oncetheabutmentwasinitiallyseated, theprosthesiswasremovedforthedefinitiveseating by tapping directly onto the titanium abutment. This seating process was continued until all of the abut- ments were definitively seated (Figs. 10 to 12). Alternatively, an abutment could have been ini- tially be loosely seated in the well of the implant, prior to the prosthesis being used to orient and seat the abutment in the well of the implant. Final or temporary cementation was achieved by first ap- plying Vaseline over the ridge area of the prosthesis to facilitate the removal of any extraneous cement. Onlyaminimumofcementwasappliedtothebores in the Trinia framework before inserting the pros- thesis in the mouth. The extraneous cement was blown away with an application of air under the prosthesis. The occlusion was evaluated and ad- justed (Figs. 13 & 14). _Conclusion Regardless of which type of material will ulti- matelybeusedtocovertheTriniaframework,itwas essentialtohaveananteriordiagnosticpositioning, waxrim,orarrangementoftheintendedteethprior tothefabricationoftheTriniaCAD/CAMframework. In our clinical case, Meyor composite denture teeth were used for the final prosthetic to assure agoodbiomechanicalforcedistributionaroundthe four SHORT® implants. The follow-ups of our pa- tients treated with the described technique was showing a good gingival response and no marginal bone loss around the platform switched implant neck of the SHORT® or ULTRA SHORT® implants (Bicon Dental Implants) used in our case presenta- tion and in 60 other cases treated in three different Implant Dentistry Centers. This technique of a fixed prosthesis on only four short implants deserves a clinical, long term, evi- dence-based study because of its low costs and reduced treatment time with minimum morbidity and good patient response._ Editorial note: A complete list of references is available fromthepublisher. I 37CAD/CAM 1_2013 Fig. 14 Prof.Mauro Marincola Via dei Gracchi,285 I-00192 Roma,Italy mmarincola@gmail.com CAD/CAM_contact