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PUBLISHED IN DUBAI www.dental-tribune.me March-April 2017 | No. 2, Vol. 7 Implant-Supported Fixed Restorations for the Partially Edentulous Arch By Prof. Gregor-Georg Zafiropoulos & Assoc. Prof. Moosa Abuzayda, UAE When restoring a partially edentu- lous arch with an implant-retained fixed restoration (fixed partial den- ture, FPDs), several procedural steps may influence the fit and function of the framework. These include: 1) the correct transfer of the implant posi- tion, 2) the correct transfer of verti- cal height and maintenance of the maxillo-mandibular relationship, 3) the determination of an optimal occlusion, and 4) the selection of implant abutments with the correct shaping and angulation.1,2 The de- scribed method allows the accurate transfer of the implant position and the recording of the interocclusal relationship using transfer key and electroformed gold copings. Figure 1. Impression system. L: titanium impres- sion post placed on the implant, R: plastic im- pression coping. B: Impression system in situ. Figure 2. A: Master cast with 2nd set of titanium impression posts; B: Transfer key in situ. MEA Scientific Meeting 2017 Preserving hard & soft tissue around implants: Predictable Strategies Steigenberger Al Dau Hotel, Hurghada, Egypt Friday 21st - Saturday 22nd April 2017 CPD: 5.5 hours Speakers: Dr. Hassan Maghaireh, Dr. Hatem Al Rashdan, Dr. Ayad Ismail & Dr. Mohammad Al Jarrah Fees: €800.00 per person - Including hotel booking and excursion For further information, or to book your place, please contact your local distributor: T: +97150 394 0701 E: info.mea@neoss.com Case A 62-year-old man with a partial edentulism of the left posterior mandible presented for implant placement and prosthetic restora- tion. Teeth #34–36 had been extract- ed due to root caries 5 years previ- ously. Two screw cylinder implants (straight line, 3.75 mm diameter, 11.5-mm length; Dentegris, Duisburg, Germany) were placed manually at a torque of 35 Ncm in the areas of teeth #19 and #21, following a two-step surgical protocol. The implants were uncovered 8 weeks after placement, system spe- cific healing abutments were placed, and a closed-tray impression was taken using a transfer system con- sisting of a titanium impression post (TImP) and a plastic impression coping (pickup, Dentegris; Fig. 1). For impression, a polyether material (Impregum; 3M ESPE, St. Paul, MN, USA) was used. To ensure that the ti- tanium impression posts remained in the exact same position, they were left on the implants until the interoc- clusal relationship was recorded (1 day later). The master cast was fabricated using system-specific implant analogs and a new set of TImPs (Fig. 2A). The cast was used to fabricate. For fabrication of a transfer key, resin copings were made on top of the TImPs (pattern resin; GC America, Inc., Alsip, IL, USA) and connected to each other using a light-curing resin (tray pink trans- parent; Omnident, Rodgau, Ger- many; Fig. 2B). The transfer key was placed on TImPs in patient’s mouth and a bite registration was made in centric occlusion using pattern resin (Fig. 3B). The TImPs were then removed from the implants and the healing abutments were replaced. The casts were placed into the articu- lator using this transfer key and bite record. In the case presented here, customizable abutments (PTIR, plat- inum-iridium; Dentegris) were used casted with CrCo alloy (Fig. 3A). Over the implant abutments, were fabri- cated: 1) a resin transfer key (pattern resin; GC America, Inc., Alsip, IL) and 2) electroformed gold copings (AGCs; AGC Galvanogold, 0.25-mm thick- ness; Wieland, Pforzheim, Germany; Fig. 3B).3–5 The master cast with the mounted implant abutments and AGCs in place was scanned, and a mock- up from clear poly(methyl meth- acrylate) (PMMA; Zenotec; Wieland, Pforzheim, Germany) as well as a temporary FPD from colored PMMA were milled (Fig. 4). At the next clinical session, the im- plant abutments were mounted on the implants using the transfer key and torqued to 35 Nm, the AGCs were placed on the abutments (Fig. 5) and the fit of the abutments was assessed with x-rays (Fig. 6). The mock-up from clear PMMA was placed over the electroformed copings, and the occlusion was checked (Fig. 7). A bite registration was made and a final im- pression was taken over the electro- formed copings and the mock-up us- ing a polyether material (Impregum; 3M ESPE; Fig. 8A). After the impres- sion had been taken, the abutments were left in the patient’s mouth and the temporary FPD from colored PMMA was placed on them using temporary (TempBond; Kerr, Orange, CA, USA; Fig. 08B). cement In the dental laboratory, a final mas- ter cast was made using the mock-up and electroformed copings to trans- fer the position of the gold implant abutments (Fig. 09A). The metal framework was milled from a CrCo alloy (Zenotec NP; Wieland, Pforz- heim, Germany) and veneered with porcelain (Vintage MP; Shofu, Ratin- gen, Germany; Fig. 09B). Afterthen, the gold copings were fixed into the framework (AGC Cem; Wieland, Pforzheim, Germany). The final FPD was fixed over the implant abut- ments using a temporary cement ÿPage D2