PubMed ID (PMID): 25874269Pages 186-208, Language: EnglishCocchetto, Roberto / Canullo, LuigiCemented implant restorations are widely used by many dentists. The traditional abutment design resembles a natural tooth prepared for a crown with a similar taper and a chamfer finish line. A frequent complication associated with implant restorations in the esthetic zones is the recession of buccal gingiva over time. Abutment morphology, among several other prosthetic factors, may play an important role in the stability of the gingival margin in esthetically sensitive areas, but this has never been thoroughly analyzed. Recently, a prosthetic technique called biologically oriented preparation technique (BOPT) has been proposed, which utilizes a feather-edge preparation on natural abutments, and it has been claimed that applying the concepts of this technique to implant abutments could improve long-term gingival margin stability. At present, there is no available evidence to confirm this claim. Moreover, some concerns may arise if this particular design is implemented in every clinical situation. With these considerations in mind, this article proposes the "hybrid abutment" design (HAD), a new design that includes a combination of the two types of features - a feather edge on the buccal side, and a chamfer finish line on the lingual side. The article also presents a rationale for the use of different abutment designs for different situations.