Biaxial flexure strength and low temperature degradation of Ce-TZP/Al2O3 nanocomposite and Y-TZP as dental restoratives

✍ Scribed by Seiji Ban; Hideo Sato; Yasuhiko Suehiro; Hideo Nakanishi; Masahiro Nawa

• Publisher: John Wiley and Sons
• Year: 2008
• Tongue: English
• Weight: 283 KB
• Volume: 87B
• Category: Article
• ISSN: 1552-4973
• DOI: 10.1002/jbm.b.31131

✦ Synopsis

Abstract

The purpose of the present study was to evaluate the mechanical durability of a zirconia/alumina nanocomposite stabilized with cerium oxide (Ce‐TZP/Al~2~O~3~ nanocomposite) in comparison to yttria‐stabilized tetragonal zirconia polycrystals (Y‐TZP) and discuss its application on ceramic dental restorations. The disk‐shaped specimens of both materials were stored in physiological saline solution at 80°C for 30 days, in 4% acetic acid at 80°C for 30 days, and in an autoclave at 121°C for 10 days. Before and after storage, specimens were subjected to the biaxial flexure test and to the determination of the monoclinic zirconia content. After autoclaving, Y‐TZP showed remarkable increasing of the content of monoclinic zirconia: 0.3 vol % before and 49.9 vol % after, and slight decreasing of biaxial flexure strength: 1046 MPa before and 892 MPa after; whereas Ce‐TZP/Al~2~O~3~ nanocomposite showed no significant difference in the monoclinic content (4.8–5.5 vol %) and the biaxial flexure strength (1371–1422 MPa) after storage in any conditions. It is concluded that, compared to Y‐TZP, the Ce‐TZP/Al~2~O~3~ nanocomposite has a high biaxial flexure strength along with a satisfactory durability in terms of low‐temperature aging degradation in above conditions. This study indicates that the Ce‐TZP/Al~2~O~3~ nanocomposite demonstrates excellent mechanical durability for dental restorations such as all‐ceramic bridges. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2008