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D2 ◊Page D1 IMPLANT TRIBUNE Dental Tribune Middle East & Africa Edition | 2/2017 Figure 3. A: Customized implant abutment. B: AGC splaced onto the implant abutment. Figure 4. A: Mock-up milled from clear PMMA. B: Temporary FPD milled from colored PMMA. Figure 5. AGCs in situ. Figure 6. Radiographic assessment of the fit of the implant abut- ments. Figure 7. Mock-up and the AGCs placed on the implant abutment. A: Fitting mock-up and AGCs in the lab. B: in situ. Figure 9. A: final master cast. B: FPD in situ. Figure 10. Rehabilitation of a partially edentulous mandible with a 8-unit fixed bridge supported by 3 implants. A: ortho- pantomograph. (Implant Provisional; Alvelogro Inc., Snoqualmie, WA, USA). Discussion Several clinical steps significantly influence the success of the restora- tion, including the accurate record- ing of the interocclusal relationship, the transfer of the correct implant position, occlusal forces and the passive fit of the framework.6 In the case described in this report used customized implant abutments, pre- fabricated titanium can also be used. However, customized abutments (casted or CAD/CAM milled) allowed the achievement of more ideal angu- lation, height, diameter, and shape. Such optimization improved the ability to address problems related to interocclusal and interproximal distances, implant angulation, and related soft-tissue responses. Although this report has described the fabrication of a three-unit FPD supported by two dental implants, this technique can also be used for the rehabilitation of larger partially edentulous areas with multiple-unit FPDs retained on more than two implants (Fig. 10). The abutments were not removed after mounting and torquing until the final restora- tion was fitted and placed. Thus, the position of the abutments remained unchanged, eliminating errors that might occur during repeated attach- ment of the abutments for various test fittings of the restoration. A proper fit of a restoration requires the accurate transfer of the intraoral implant position to the master cast and a precise fit to the abutment can be achieved with AGCs.7,8 The use of a mock-up allows not only the evaluation of FPD fit, occlusion, and shape but also the fabrication of an exact final master cast, because the AGCs remain in a fixed position while impressions are taken. Fur- thermore, any necessary change in shape or occlusion can also be made on the mock-up and transferred to the final denture. Although this technique requires one or two more clinical treatment Figure 8. A: Final impression over the mock-up and the gold copings. B: Temporary FPD in situ. sessions than other traditional tech- niques, this does not represent a real disadvantage given the superiority of the final result. The disadvantages of this method include the higher cost and the need for a very skilled laboratory technician. References 1. Stamoulis K. Intraoral registration coping formation using an interim restoration as a matrix. J Prostho- dont 2010;19:406–408 2. Ntounis A, Pelekanos S. Custom copings for accurate impressions of multiple internal connection im- plants. Implant Dent 2010;19:365– 369 3. Hoffmann O, Beaumont C, Tata- kis DN, Zafiropoulos GG. Telescopic crowns as attachments for implant supported restorations: a case series. J Oral Implantol 2006;32:291–299 4. Zafiropoulos GG, Hoffmann O. Five-year study of implant place- ment in regenerated bone and reha- bilitation with telescopic crown re- tained dentures: a case report. J Oral Implantol 2009;35:303–309 5. Zafiropoulos GG, Deli G, Hoffmann O, Rebbe J, Thielen U, Beaumont C. Zirconia removable telescopic den- tures retained on teeth or implants for maxilla rehabilitation. Three- year observation of three cases. J Oral Implantol 2010;36;455–465 6. Wood MR, Vermilyea SG. A review of selected dental literature on evi- dence-based treatment planning for dental implants: report of the Com- mittee on Research in Fixed Pros- thodontics of the Academy of Fixed Prosthodontics. J Prosthet Dent 2004;92:447–462 7. Zafiropoulos GG, Hoffmann O. Five-year study of implant place- ment in regenerated bone and reha- bilitation with telescopic-crown re- tained dentures. A case report. J Oral Implantol 2009;35:303–309 8. Biewer ZP. Development of the G.E.S. electroforming technique: biocompatible, corrosion-free pro- duction of telescopic crowns. J Dent Technol 1999;16:24–29 Gregor-Georg Zafiropoulos Professor of Periodontology MBRU, Hamdan Bin Mohammed College of Dental Medicine E: Gregor.zafiropoulos@mbru.ac.ae Moosa Abuzayda Associate Professor of Prosthodontics MBRU, Hamdan Bin Mohammed College of Dental Medicine E: Moosa.Abuzayda@mbru.ac.ae Interview: “The future of ceramic implants is really bright for many reasons” By DTI When it comes to materials used in implantology, titanium and tita- nium alloys have always been the material of choice. However, recent advancements in the functionality of ceramic implants have positioned them as a viable, metal-free alterna- tive with antiallergenic properties and greater aesthetic appeal. The International Academy of Ceramic Implantology (IAOCI) is an associa- tion entirely dedicated to ceramic and metal free alternatives to met- al-based implants. Dental Tribune Online spoke with the President and co-founder of the IAOCI, Dr. Sammy Noumbisssi, about the association’s mission, as well as current trends in the field of ceramic implantology. Dental Tribune Online: How have ceramic implants pro- gressed since their initial de- velopment in the late 1960s? Dr. Sammy Noumbissi: Ceram- ic implants were born out of a desire for a material that would appear similar to natural teeth and be just as functional. They were a response to early concerns about the long-term stability and health effects of metal alloys being embedded in bone and exposed to the oral environment. Early ceramic implants were mostly made of one ceramic compound, such as alumina or zirconia. They were all monocrystalline in compo- sition and were initially found to be vulnerable to functional stresses or premature structural breakdown. Alumina was prone to fracture and zirconia displayed low temperature degradation and poor suitability to the high humidity in the oral envi- ronment. Starting in the mid-1980s, advances in manufacturing and technology led to the development of ceramic composites. These composites were made by combining specific and different bioceramics that were known to have unique physical and chemical properties. These advances created new and more structurally stable polycrystalline bioceramics with greatly improved functional properties. This is how we developed dental implants that are made of ce- ramic composites, such as alumina- toughened zirconia and hot isostatic- pressed yttria-stabilized zirconia. In terms of design, the early im- plants, for the most part, were one- piece designs. This was because dur- ing the initial testing of the implants, structural failures migrated to the connection area between the im- plants and the abutments. Around 2014, ceramic implant manufac- turers started releasing two-piece cemented zirconia implants. This signaled a new era in ceramic im- plantology, because the flexibility that was once only available with ti- tanium implants had finally come to ceramic implants. More recently, two-piece, screw-retained ceramic implants with metal and metal-free screws have been developed, no longer limiting them to cementable restorative options. What are some of the issues associated with metal im- plants, and are these negated with ceramic implants? Metal implants are well researched, documented and have been very successful. There is a multitude of implants on the market and with that has come along different manu- facturing protocols. As a result, we have observed a steady increase in alloy elements added to titanium in order to improve its physical proper- ties. The problems begin when the metal implant, highly alloyed or not, is subjected to functional stresses, galvanism, body fluids and the harsh ÿPage D3