The CM prepared from compact alloy was not cytotoxic at any tested dilutions, whereas CM from alloy microparticles showed dose-dependent cytotoxicity (90% CM and 45% CM versus control; p < 0.005). Ni-Cr microparticles showed less corrosion resistance and lower biocompatibility than compact alloy. This could

affect health on long-term exposure, especially in sensitized individuals. “
“Purpose: The aim of this study was to evaluate the effect of finish line design on the fatigue, fracture RG7204 purchase resistance, and failure type of veneered zirconia restorations. Materials and Methods: A CAD/CAM system (Cercon) was used to prepare zirconia frameworks (0.5 mm thick) for a maxillary central BAY 80-6946 price incisor. Three finish line designs were evaluated: a complete narrow chamfer, a narrow chamfer with a lingual ledge, and a complete ledge. The prepared frameworks were veneered using a press-on ceramic (Ceram Press) and were cemented on the corresponding prepared teeth using a resin cement (Panavia F2.0). The cemented specimens were thermocycled, subjected to dynamic fatigue, and finally loaded till fracture. Fractured specimens were examined under a scanning electron microscope to assess fracture type. One-way ANOVA and Bonferroni post hoc tests were used to analyze the data (α= 0.05). Results: The finish line design did not

have any significant statistical influence on the fracture resistance (F = 1.9, p= 0.346) or on the failure type of the tested specimens. Adjusted R squared value (R = 0.049) indicated a weak correlation between finish line design and fracture load of the tested specimens. All specimens failed due to cracking and fracture of the veneer ceramic. Meanwhile, the framework remained entirely intact. Three narrow chamfer finish line specimens demonstrated adhesive fracture of the veneer ceramic during dynamic fatigue testing, related to overextension of the veneer ceramic during the layering procedure. Conclusion: Within the limitations of this study, the finish line design did not influence the

selleck fatigue or the fracture resistance of veneered zirconia crowns. Selection of any of the finish line designs should be based on the clinical condition of the restored tooth. “
“Purpose: The aim of this investigation was to explore the relationship between an objective computer measurement of color difference (ΔE) and subjective clinical opinion of a “good” color match between silicone samples and skin. Materials and Methods: In Part 1 of this study, silicone samples were colored to match the skin of 19 African-Canadian subjects based on spectrophotometric measurements and pigment formulae determined by computerized color formulation software. Four iterative samples were prepared for each subject; a ΔE value was recorded for each sample to represent the color difference between the silicone sample and skin.