Im vorliegenden Artikel nehmen die Autoren Bezug auf einen in der ersten Ausgabe der Zeitschrift IMPLANTOLOGIE vor 25 Jahren veröffentlichten Fall zweier zentraler Oberkieferfrontzahnimplantate. Der Fall ist seit Eingliederung der Implantatkronen über 27 Jahre nachdokumentiert. Es wird anhand dieses Beispiels diskutiert, was im Jahre 2017 anders gemacht werden würde als in den Jahren 1990 bis 1992. Anhand dieser Diskussion werden Entwicklungen und deren Hintergründe deutlich gemacht, die für Implantatversorgungen im ästhetischen Bereich klinisch relevant sind, um eine Langzeitstabilität von Hart- und Weichgeweben zu erzielen. Dazu zählen unterschiedliche Operationstechniken und das zeitliche Vorgehen, Inzisionstechniken in der ästhetischen Zone, die Anwendung von Bindegewebetransplantaten sowie die Unterschiede zwischen zementierten und verschraubten Implantatsuprastrukturen. Schlagwörter: Fallbericht, Frontzahnimplantat, ästhetische Zone, Langzeitergebnis, Erfolgsfaktor, operatives Vorgehen, Inzision, Bindegewebetransplantat, Zementierung, Verschraubung

Purpose: To quantify the cement remnants on titanium and zirconia abutment analogs after cement removal by resin and steel scalers. Materials and Methods: Defined areas of titanium or zirconia cylindric samples were covered with thin cement rings of zinc oxide phosphate (ZOP), glass ionomer (GIC), carboxylate (CAB), zinc oxide-eugenol (ZOE), or zinc oxide-eugenol-free (ZOEF). The cements were mixed with liquid-to-powder ratios of 50%, 75%, 100%, and 150% of powder. After setting and aging by thermocycling, each specimen was scaled by a blinded, trained clinician. Standardized digital photos of the scaled areas were analyzed according to a four-point classification scheme for remnants, and the results were analyzed statistically. Results: The main effects of the independent variables "cement type," "abutment material," and "scaler" showed statistically significant differences for all variables. Such differences were also found with regard to the interactions of the variables "cement type" and "material" as well as for the type of cement and scaler. The extent of remnants after scaling differed significantly between titanium and zirconia. Steel scalers achieved statistically significantly better cleaning than resin scalers. The powder-to-liquid ratio of all luting agents significantly influenced the extent of cement surplus after scaling. ZOEF was the only type of cement that could be more successfully removed from titanium than from zirconia. Conclusions: Nearly complete removal of ZOE could be achieved. This luting agent was not as sensitive to aberrant mixing ratios or to resin or steel scaling as the other types of cement. With the exception of ZOEF, zirconia surfaces were easier to clean. After removal of most of the remnant, some cements showed a barely visible thin greasy or powdery layer. Schlagwörter: cement, cement remnant, luting agent, scaler, titanium, zirconia