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issue 2016 — 15 Advanced Implant Esthetics Article or an overcontour encourages apicaliza- tion of the gingival margin, which is gen- erally deleterious buccally (Figs. 6a–c). After stabilizing the soft-tissue margin, smallamountsofresinplacedmesiallyand distally with a brush on the temporary toothallowsomepressuretobeplacedon the papilla according to the cervical con- touring concept of Bichacho and Lands- berg10 and, in this way, to optimize the fill- ingofanygapsandtheemergenceprofile. Buccally,the gingival level orthe crown zenith can be moved by modifying the temporary tooth (Figs. 6d & e). In order to reduce any excess cement and to allow ittoescapeduringsetting,a0.75 mmhole can be drilled on the palatal side in the in- cisal half of the temporary crown.11 Optimize the emergence profile by progressive modification of the temporary crown. — Taking impression In order to comply with OAOT, the ideal, provided that the abutment has not been adjusted, is to take an impression of the abutment. A resin impression coping fab- ricated over an abutment identical to the one seated in the mouth makes it possible to transfer the position of the abutment without unscrewing it (Figs. 7a & b). An abutment and a laboratory copy are posi- tioned in the impression and, if it is thought that the abutment is not suitable for the permanent prosthesis, one could opt for a NobelProcera abutment (Nobel Biocare) ora modified abutment (Fig. 7c). Take an impression of the abutment without removing it. — Abutment Material According to several publications,9, 12, 13 ti- tanium and aluminum and zirconium ox- ides are the only materials that allow attachment of soft tissues on the abut- ment. For Van Brakel et al.,14 in a study on humans, there is no difference between titanium and zirconia regarding biology, with just a slight advantage in favor of zirconia for sulcular depth after three months. Gold alloys cause apicalization of theattachmenttothetitanium12 oftheim- plant, but this conclusion has been con- testedbyLinkeviciusandApse.15 Agoldal- loy supports less dental plaque after 4 h in vitro,16 but more than titanium or zirco- nia does after four days in vivo.17 Thus, there is no consensus yet in the medical literature concerning the superiority of one material over another in terms of bi- ology. Zirconia and gold alloys have superior esthetic qualities when the abutment supports a glass-ceramic crown in vitro18 orinvivo19 ,comparedwithtitanium.When the implant site of the lateral incisor is wide(> 6.5 mm),selectinga3.3or3.5 mm diameter implant makes it possible to use zirconiaabutments.However,themajority of small-diameter implants on the market do not include zirconia abutments in their prosthetic ranges for reasons of mechan- ical resistance. In such cases, commercial titanium abutments or abutments made by 3-D machining are used. In this situa- tion, the thickness of buccal soft tissue must exceed 2 mm, which is the requisite dimension specified by Van Brakel et al.20 toavoidtherebeinganydifferenceinlight reflection discernible by the human eye between a titanium and a zirconia abut- ment. Shape Incement-retainedprostheses,excessce- menthasbeenfoundtobeacauseofperi- implantitis.21–28 Linkevicius et al.29 have demonstrated in an in vitro experiment that there is a correlation between the Figs. 6a–e Buccal compression (a). Creation of a concave pro- file on the provisional crown (b). Provisional clini- cal outcome: The shape of the incisal edge also plays a role in the esthetic result (c). Resin applied with a brush to distalize the zenith (UNIFAST III; d). Emer- gence profile optimized by the provisional crown (e). Fig.6a Fig.6d Fig.6e Fig.6b Fig.6c Article_Russe_00-00.qxp_Layout 1 02.03.16 20:52 Seite 4 Article_Russe_00-00.qxp_Layout 102.03.1620:52 Seite 4