%0 Journal Article %T A Comparison of Fracture Resistance of Zirconia Copings Made with CAD/CAM Technology and Slip Casting Technique %J Journal of Dentistry %I Shiraz University of Medical Sciences %Z 2345-6485 %A Torabi, K. %A Ahangari, AH. %A Salehi, S. %A Motamedi, M. %D 2011 %\ 12/01/2011 %V 12 %N 4 %P 327-333 %! A Comparison of Fracture Resistance of Zirconia Copings Made with CAD/CAM Technology and Slip Casting Technique %K Zirconia Coping %K CAD/CAM %K Slip casting %R %X Statement of Problem: Zirconia has been introduced as an appropriate structure for fabricating metal free copings. A major advantage of such restorations is esthetic concerns; however, due to its high strength, zirconia can also be used in posterior areas. One of the recent methods of making these restorations is CAD/CAM machines. Purpose: This study aimed to evaluate the fracture resistance of zirconia copings fabricated by two methods, CAD/CAM and slip casting Materials and Method: 32 brass dies were fabricated for this study and divided into two groups of 16 dies each. Zirconia copings were made by CAD/CAM machine for one group and by slip casting method for the other. The copings were cemented to dies by a resin-modified glass ionomer (GC plus). A hardened steel ball with a diameter of 5 mm was used to apply the load to the copings in the long axis of the dies at a crosshead speed of 0.5 mm/min. Then the amount of force needed to fracture each coping was recorded. Independent Sample T-test was used to compare the two groups. Results: The average of fracture resistance for the CAD/CAM group was 1411± 424 N and for the slip cast group it was 1542±412 N, having no significant difference ( p > 0.05). Conclusion: Zirconia copings made by CAD/CAM and slip casting methods have no significant difference in fracture resistance. %U https://dentjods.sums.ac.ir/article_46335_1a14aeb96e49dd515b05661b01c3330a.pdf