Mechanical properties and short-termin vivo evaluation of yttrium-oxide-partially-stabilized zirconia

✍ Scribed by Christel, P. ;Meunier, A. ;Heller, M. ;Torre, J. P. ;Peille, C. N.

• Publisher: John Wiley and Sons
• Year: 1989
• Tongue: English
• Weight: 991 KB
• Volume: 23
• Category: Article
• ISSN: 0021-9304
• DOI: 10.1002/jbm.820230105

✦ Synopsis

Yttrium-oxide-partially-stabilized zirconia (YPSZ) belongs to a new class of ceramics exhibiting an improved toughness when compared to alumina. The toughening mechanism is related to a martensitic-like transformation of tetragonal metastable grains into a monoclinic state occurring at the crack tip. Specific tests showed that YPSZ exhibited a high bending strength (900-1200 MPa), a low Young's modulus (200 GPa), and a high toughness (Klc = 9-10 MN/m3"). Its average grain size of 0.5 pm allows a surface roughness as low as 0.008 pm. Sterilization or aging in saline solution at room temperature for 100 days did not affect the toughness of tl.is material. Cylindrical YPSZ samples, manufactured by cold isostatic pressing and sintering, were implanted in the paraspinal muscles in the rat up to 12 weeks. The tissue reaction was evaluated with reference to alumina (IS0 requirements) by means of quantitative histomorphometry. No significant differences were found between YPSZ and alumina for both the membrane thickness and cell distributions surrounding the implants.