Oberflächenveränderung verschiedener zahnmedizinischer Werk-stoffe nach in-vitro Alterung

Susceptibility of different restorative materials to toothbrush abrasion and coffee staining Objective: The aim of this study was to evaluate the susceptibility of different restorative materials to surface alterations after an aging simulation. Methods: Specimens (n=15 per material) of five different restorative materials (CER: ceramic/Vita Mark II; EMP: composite/Empress Direct; LAV: CAD/CAM composite/Lava Ultimate; COM: prefabricated composite/Componeer; VEN: prefabricated composite/Venear) were produced. Whereas CER was glazed, EMP and LAV were polished with silicon polishers, and COM and VEN were left untreated. Mean roughness (Ra and Rz) and colorimetric parameters (L*a*b*), expressed as colour change (E), were measured. The specimens underwent an artificial aging procedure. After baseline measurements (M1), the specimens were successively immersed for 24 hours in coffee (M2), abraded in a toothbrushing simulator (M3), immersed in coffee (M4), abraded (M5) and repeatedly abraded (M6). After each aging procedure (M2-M6), surface roughness and colorimetric parameters were recorded. Differences between the materials regarding Ra/Rz and E were analysed with a nonparametric ANOVA analysis. The level of significance was set at α=0.05. Results: The lowest roughness values were obtained for CER. A significant increase in Ra was detected for EMP, COM and VEN compared to CER. The Ra/Rz values were found to be highly significantly different for the materials and measuring times (M) (p<0.0001). Regarding E most alterations were found for EMP and COM, whereas CER and LAV remained mostly stable. The E values were significantly different for the materials and M (p<0.0001). Conclusion: The ceramic and the CAD/CAM composite were the most stable materials with regard to roughness and colour change and the only materials that resulted in Ra values below 0.2 μm (the clinically relevant threshold). Venears and Componeers were more inert than the direct composite material and thus might be an alternative for extensive restorations in the aesthetic zone.

Tarif und Tarifanpassung in der Krankenversicherung: ein juristischer, ökonomischer und methodischer Blick auf den ambulanten Bereich

Wie im Krankenversicherungsrecht die Leistungserbringer (Ärzte, Spitäler, Pflegeheime etc.) entschädigt werden, legt das Krankenversicherungsgesetz nur in Grundzügen fest. Viele wichtige Fragen werden erst auf Tarifebene geklärt. Tarife müssen angepasst werden. Neue Behandlungsmethoden entstehen; technische Veränderungen müssen beachtet werden; die Alterung der Gesellschaft schreitet voran; die Qualität der Behandlung soll erhöht werden. Tarifanpassungen gehören zu den besonders schwierigen Fragen. Und auch dazu gibt das Krankenversicherungsgesetz kaum Vorgaben. Die Publikation von Kieser/Oggier/Bührer greift das Thema grundsätzlich in einem weit gefassten interdisziplinären Bogen, mit Fokus auf den ambulanten Bereich, auf. Es werden Antworten und Einordnungen vorgeschlagen und begründet. Damit will die Publikation den Vorgang der Tarifanpassung kritisch und fundiert begleiten.