Effect of surface treatment on flexural strength of zirconia bars
Section snippets
Material and methods
Bar-shaped specimens (25 × 3 × 1 mm) were produced by cutting and sintering CAD/CAM zirconia milling blocks (Procera Zirconia; Nobel Biocare AB, Göteborg, Sweden). The bars were polished in a customized rotating metallographic polishing device (EcoMet; Buehler Ltd, Lake Bluff, Ill) and divided into 3 groups. One selected surface of each specimen received one of the following surface treatments, which simulated the surface damage that could be introduced during common clinical and laboratory
Results
Compared to the mean (SD) flexural strength of polished zirconia specimens, 1200 (136) MPa, both types of induced surface damage resulted in a significant reduction in the flexural strength of almost 50%. There was a significant interaction between the type of surface damage and the restoration method (P<.001). For the ground specimens, all restoration methods resulted in a significant (P<.001) regain in strength; the polishing procedure was the most effective, resulting in a mean (SD) flexural
Discussion
According to the findings of this study, surface damage to zirconia specimens can be repaired by using the proper method of surface restoration, resulting in a partial or complete regain of lost strength. Thus, the proposed hypothesis was accepted. Despite the fact that fracture strength tests do not reproduce intraoral loading conditions, they offer a standardized environment in which the variables under investigation can be well controlled. The selected test was easily conducted and offers
Conclusions
Within the limitations of this study, a regain in lost strength of zirconia was possible using the 3 suggested surface restoration methods. For airborne-particle-abraded zirconia, resin bonding was most effective, while polishing with diamond points achieved the best results for ground zirconia.
Acknowledgments
The authors thank the research enhancement program (Alex Rep) of Alexandria University, Alexandria, Egypt, and the Scientific Research Foundation for Returned Overseas Chinese Scholars, State Education Ministry (SRF for ROCS, SEM), for supporting this study.
References (31)
- et al.
State of the art of zirconia for dental applications
Dent Mater
(2008) - et al.
Stabilized zirconia as a structural ceramic: an overview
Dent Mater
(2008) - et al.
Strength influencing variables on CAD/CAM zirconia frameworks
Dent Mater
(2008) - et al.
The effect of surface grinding and sandblasting on flexural strength and reliability of Y-TZP zirconia ceramic
Dent Mater
(1999) - et al.
Influence of surface and heat treatments on the flexural strength of Y-TZP dental ceramic
J Dent
(2005) - et al.
Influence of surface and heat treatments on the flexural strength of a glass-infiltrated alumina/zirconia-reinforced dental ceramic
Dent Mater
(2005) - et al.
Fatigue of zirconia under cyclic loading in water and its implications for the design of dental bridges
Dent Mater
(2007) - et al.
The influence of alumina abrasion and cement lute on the strength of a porcelain laminate veneering material
J Dent
(2004) - et al.
Survival of Dicor glass-ceramic dental restorations over 14 years: Part I. Survival of Dicor complete coverage restorations and effect of internal surface acid etching, tooth position, gender, and age
J Prosthet Dent
(1999) - et al.
Survival of Dicor glass-ceramic dental restorations over 14 years. Part II: effect of thickness of Dicor material and design of tooth preparation
J Prosthet Dent
(1999)
Effect of surface finish on the osseointegration of laser-treated titanium alloy implants
Biomaterials
Influence of grinding, sandblasting, polishing and heat treatment on the flexural strength of a glass-infiltrated alumina-reinforced dental ceramic
Biomaterials
Analyses of layer-thickness effects in bilayered dental ceramics subjected to thermal stresses and ring-on-ring tests
Dent Mater
Durability of the resin bond strength to zirconia ceramic after using different surface conditioning methods
Dent Mater
Bridging the gap between clinical failure and laboratory fracture strength tests using a fractographic approach
Dent Mater
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Support for this study was provided by the research enhancement program (Alex Rep) of Alexandria University, and the Scientific Research Foundation for Returned Overseas Chinese Scholars, State Education Ministry (SRF for ROCS, SEM), grant number 20091001-9-4.