Alumina-toughened zirconia for dental applications: Physicochemical, mechanical, optical, and residual stress characterization after artificial aging

Author(s)

Bergamo, Edmara T. P. ^[1] ; Cardoso, Karina B. ^[1] ; Lino, Lucas F. O. ^[1] ; Campos, Tiago M. B. ^[2] ; Monteiro, Kelli N. ^[3] ; Cesar, Paulo F. ^[3] ; Genova, Luis A. ^[4] ; Thim, Gilmar P. ^[2] ; Coelho, Paulo G. ^[5] ; Bonfante, Estevam A. ^[1]

Affiliation

^[1] Univ Sao Paulo, Dept Prosthodont & Periodontol, Bauru Sch Dent, Al Otavio Pinheiro Brisola 9-75, BR-17012901 Bauru, SP - Brazil

^[2] Aeronaut Technol Inst, Dept Phys, Sao Jose Dos Campos, SP - Brazil

^[3] Univ Sao Paulo, Sch Dent, Dept Biomat & Oral Biol, Sao Paulo, SP - Brazil

^[4] Inst Res Nucl Energy, Ctr Mat Sci & Technol, Sao Paulo, SP - Brazil

^[5] NYU, Dept Biomat & Biomimet, Hansjorg Wyss Dept Plast Surg Mech & Aerosp Engn, New York, NY - USA

• Document type: Journal article
• Source: JOURNAL OF BIOMEDICAL MATERIALS RESEARCH PART B-APPLIED BIOMATERIALS; v. 109, n. 8, p. 1135-1144, AUG 2021.
• Web of Science Citations: 2

Abstract

To characterize the physicomechanical properties of an alumina-toughened zirconia (ATZ). ATZ synthesis consisted of the addition of alumina particles in an yttria-stabilized tetragonal zirconia polycrystals (3Y-TZP) matrix. Specimens were obtained by uniaxial and isostatic pressing ATZ and 3Y-TZP powders and sintering at 1600 degrees C/1 h and 1550 degrees C/1 h, respectively. Crystalline content and residual stress were evaluated using X-ray diffraction (XRD). Microstructure was characterized by scanning electron microscopy (SEM). Optical properties were determined by reflectance test. Mechanical properties were assessed by biaxial flexural strength test. All analyses were performed before and after aging (134 degrees C, 20 h, 2 bar). XRD and SEM revealed a typical ATZ and 3Y-TZP crystalline content, chiefly tetragonal phase, with a dense polycrystalline matrix, though a smaller grain size for ATZ. Aging triggered a similar monoclinic transformation for both systems; however, ATZ exhibited higher residual compressive stresses than 3Y-TZP. While as-processed 3Y-TZP demonstrated significantly higher characteristic strength relative to ATZ, no significant difference was observed after aging (similar to 215 MPa increase in the ATZ strength). ATZ presented significantly higher opacity relative to 3Y-TZP, although aging significantly increased the translucency of both systems (increase difference significantly higher in the 3Y-TZP compared to ATZ). ATZ physicomechanical properties support its applicability in the dental field, with a lower detrimental effect of aging relative to 3Y-TZP. (AU)

• FAPESP's process: 12/19078-7 - Development and processing of Al2O3-ZrO2 translucent composite for CAD/CAM monolithic prostheses: the effect of aging on biaxial flexural strength
• Grantee: Estevam Augusto Bonfante
• Support Opportunities: Research Grants - Young Investigators Grants
• FAPESP's process: 19/08693-1 - Experimental glass-infiltrated alumina-zirconia composites: characterization of microstructure, optical and mechanical properties.
• Grantee: Edmara Tatiely Pedroso Bergamo
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 16/18818-8 - Multi-User Equipment approved in grant 2012/19078-7: ElectroPuls E3000 Linear-Torsion All-Electric dynamic test instrument package
• Grantee: Estevam Augusto Bonfante
• Support Opportunities: Multi-user Equipment Program
• FAPESP's process: 18/19094-9 - Experimental composits 80%ZrO2 -20%Al2O3: microstructural, optical and survivor characterization
• Grantee: Lucas Fracassi de Oliveira Lino
• Support Opportunities: Scholarships in Brazil - Master