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7 CASE STUDY Fig. 1: Cross-section of a hybrid abutment. The titanium base with the bonded zirconium oxide sleeve is screw- retained to the implant. The fabrication precision (zirconium sleeve) and thus the bonding gap to the titanium base play an elementary role for the quality of the outcome. Example for hybrid solutions in daily dental routine: Hybrid ceramic material: plastic and ceramic Hybrid crown implant abutment and monolithic crown Hybrid abutment: High load-bearing capacity of a metal base and the esthetic options of a ceramic abutment abutments. These days, they are only at- tributed with limited options. Why? The requirements for an abutment include stability, resistance to wear at the inter- face (titanium, zirconium oxide), resistance to aging and precision. Zirconium oxide needs to be partially downgraded in this context. In particular this is open to doubts regarding resistance to aging in the aque- ous environment in the oral cavity (temper- ature degradation) and the precision when compared with titanium abutments. Here, metallic structures are superior, whereby single piece titanium abutments can prove limiting in terms of esthetics (color shift). The intelligent alternative is two-piece abutments (hybrid abutments) and thus the combination between the positive ma- terial properties of metal and the optical as well as biocompatible bene ts of ceramic. Two-piece abutments consist of an assem- bled bonding base (titanium) to which the customized CAD/CAM-guided fabricated zirconium sleeve is bonded. This combines the “best” of metal and zirconium oxide in a single assembly. A major advantage of two-piece abutments is the validated maximum safety [1]. In-vitro studies have shown high breaking load values, even under high chewing forces, for example in the posterior region. In addition, the high- gloss polished sub-mucosal zirconium ox- ide abutment supports optimal tissue for- mation. The fabrication procedure CAD construction of the zirconium oxide sleeve is performed according to the emer- gence pro le. The titanium bonding base is complemented from the virtual library analog to the connecting geometry and connected ush to the zirconium oxide abutment via bonding (Fig. 1) . In principle the laboratory does not require an own CAD/CAM system for fabricating the hy- brid abutment. The DEDICAM (CAMLOG) fabrication services provider offers two dif- ferent options. 1. Lab-side: fabrication is performed in the usual CAD/CAM manner with com- ponents from the original CAD library (CAMLOG). 2. Outsourcing: the DEDICAM scanning and design service is employed. After approval of the construction data, the abutment construction is implemented 1:1. Outsourcing! What does perfection mean? No matter whether fabricated in the labo- ratory or by a fabrication service provider, the perfect t of the zirconium oxide sleeve to the titanium base guarantees maximum safety. Here, it should be ensured that the titanium base offers suf cient retention. It is recommended not to fall below a height of 5 mm. The milled zirconium ox- ide sleeve should t the titanium base such that marginal resistance can be felt during placement. A loose t is contraindicated the same as stiffness or friction. In terms of t one should consider the fabrication strategies. Of course it is possible to fabricate the abutment, designed with the CAD soft- ware, in the laboratory milling machine from zirconium oxide. However, a number of aspects interact here. In part, they ex- ceed the core competence of the dental technician and can only be complied with under perfect conditions in the laboratory. This includes calibration of the milling ma- chine, a milling machine with perfect and consistent cutting properties or a sintering process (heating and cooling rates, tem- perature, sintering stabilizer ...). Can we really and consistently comply with these many in uencing parameters in the labo- ratory? In our opinion no dental technician will be able to achieve these perfect milling properties daily at a high level of predicta- bility. In this aspect, centralized fabrication with its certi ed quality processes is supe- rior. To fully meet the requirements for an abutment, the route via an external part- ner (DEDICAM) meets the required perfec- tion. DEDICAM is dedicated exclusively to the fabrication of implant superstructures. We, as a treatment team, achieve consist- ent perfect quality results and a material quality from this type of highly competent “extended workbench” which can only be