The effect of adhesive luting agent-dentinal surface interactions on compressive strength of two types of all-ceramic crowns

This research compared the compressive strength of two types of all-ceramic crown (Hi-Ceram and Duceram) as affected by selected luting cements (Zn phosphate, glass ionomer and composite resin cement). Thirty crowns of similar size and shape were constructed (15 crowns of each tested material) to fit a standard posterior tooth preparation. Five crowns from each material were cemented by one of the tested cements. The cemented crowns were loaded until catastrophic failure. A two-way analysis of variance was performed and showed that the type of utilized cement had a significant effect on the compressive strength being that Panevia Ex. resin cement the most effective one followed by glass ionomer and then finally zn phosphate cement. Statistical analysis also showed that Hi-Ceram crowns were more resistant to occlusal load than Duceram.     

完善耶列姆矿床含重晶石铅锌矿的选矿工艺

试验了５种流程选别铂锌重晶石矿，采用再磨铅祖精矿或再磨铅粗精矿和锌黄铁矿粗精矿的流程可以获得最好的结果和经济效益。