Effect of different treatments on the flexural strength of fully versus partially stabilized monolithic zirconia

Taiseer A Sulaiman; Aous A Abdulmajeed; Khalil Shahramian; Lippo Lassila

doi:10.1016/j.prosdent.2016.10.031

Effect of different treatments on the flexural strength of fully versus partially stabilized monolithic zirconia

J Prosthet Dent. 2017 Aug;118(2):216-220. doi: 10.1016/j.prosdent.2016.10.031. Epub 2017 Jan 31.

Authors

Taiseer A Sulaiman¹, Aous A Abdulmajeed², Khalil Shahramian³, Lippo Lassila⁴

Affiliations

¹ Assistant Professor, Department of Operative Dentistry, School of Dentistry, University of North Carolina, Chapel Hill, NC. Electronic address: sulaiman@unc.edu.
² Assistant Professor, Department of General Practice, School of Dentistry, Virginia Commonwealth University, Richmond, Va.
³ Doctoral student, Department of Prosthetic Dentistry and Turku Clinical Biomaterials Centre, Institute of Dentistry, University of Turku, Turku, Finland.
⁴ Associate Professor and Laboratory Manager, Department of Prosthetic Dentistry and Turku Clinical Biomaterials Centre, Institute of Dentistry, University of Turku, Turku, Finland.

PMID: 28159339
DOI: 10.1016/j.prosdent.2016.10.031

Abstract

Statement of problem: Recent monolithic zirconia materials used for indirect restorations are predominantly fully stabilized zirconia with claims of enhanced optical properties. These restorations may behave differently from the conventional partially stabilized zirconia restorations, which may negatively affect some of the core properties required for restoration success.

Purpose: The purpose of this in vitro study was to evaluate and compare the effects of staining, airborne-particle abrasion, and artificial aging on the flexural strength of fully and partially stabilized zirconia material.

Material and methods: Each partially stabilized monolithic zirconia (PSZ) and fully stabilized zirconia (FSZ) material and a zirconia core material (control) were prepared as bar-shaped specimens (2×2×25 mm) and divided into 6 groups (n=8/subgroup): regular sintering, vacuum sintering, stained, airborne-particle abrasion, artificially aged regular sintering, and artificially aged vacuum sintering. Critical load to fracture was determined for all groups by using monotonic uniaxial loading in accordance with International Organization for Standardization standard 6872. Data were analyzed using univariate analysis of variance, followed by the Tukey honest significant difference post hoc test (α=.05).

Results: The control and PSZ (1034 and 1008 MPa) displayed a significantly higher (P<.05) flexural strength than FSZ (582 MPa). Airborne-particle abrasion significantly (P<.05) enhanced the strength of the control and PSZ (1413 and 1227 MPa) but significantly (P<.05) reduced the flexural strength of the FSZ (442 MPa). Staining, artificial aging, and vacuum sintering had no significant effects on any of the groups.

Conclusions: Fully stabilized zirconia may behave differently from conventional PSZ, especially with regard to airborne-particle abrasion, which may weaken the FSZ. The strength of PSZ is approximately double the strength of FSZ. Both of the zirconia materials showed resistance to artificial aging.

Publication types

Comparative Study

MeSH terms

Dental Materials*
Dental Stress Analysis
Materials Testing*
Pliability
Stress, Mechanical
Zirconium*

Substances

Dental Materials
Zirconium
zirconium oxide