Effect of different aging methods on the mechanical behavior of multi-layered ceramic structures
| Autor: | Alvaro Della Bona, Paulo Francisco Cesar, Jason A. Griggs, K.A. Fukushima, Márcia Borba, M.D. Araujo, Humberto Naoyuki Yoshimura |
|---|---|
| Rok vydání: | 2016 |
| Předmět: |
Dental Stress Analysis
Ceramics Materials science Surface Properties Scanning electron microscope medicine.medical_treatment 02 engineering and technology Autoclave 03 medical and health sciences 0302 clinical medicine Flexural strength Materials Testing Stereo microscope Aluminum Oxide medicine General Materials Science Cubic zirconia Ceramic Composite material General Dentistry Tension (physics) 030206 dentistry 021001 nanoscience & nanotechnology Dental Porcelain Dental Veneers Mechanics of Materials visual_art Microscopy Electron Scanning visual_art.visual_art_medium Veneer Stress Mechanical Zirconium 0210 nano-technology |
| Zdroj: | Dental Materials. 32:1536-1542 |
| ISSN: | 0109-5641 |
| DOI: | 10.1016/j.dental.2016.09.005 |
| Popis: | To evaluate the effect of two aging methods (mechanical cycling and autoclave) on the mechanical behavior of veneer and framework ceramic specimens with different configurations (monolithic, two and three-layers).Three ceramics used as framework for fixed dental prostheses (YZ-Vita In-Ceram YZ; IZ-Vita In-Ceram Zirconia; AL-Vita In-Ceram AL) and two veneering porcelains (VM7 and VM9) were studied. Bar-shaped specimens were produced in three different designs: monolithic, two layers (porcelain-framework) and three layers (porcelain-framework-porcelain). Specimens were tested for three-point flexural strength at 1MPa/s in 37°C artificial saliva. Three different experimental conditions were evaluated (n=10): control; mechanical cycling (2Hz, 37°C artificial saliva); and autoclave aging (134°C, 2 bars, 5h). Bi-layered specimens were tested in both conditions: with porcelain or framework ceramic under tension. Fracture surfaces were analyzed using stereomicroscope and scanning electron microscopy. Results were statistically analyzed using Kruskal-Wallis and Student-Newman-Keuls tests.Only for AL group, mechanical cycling and autoclave aging significantly decreased the flexural strength values in comparison to the control (p0.01). YZ, AL, VM7 and VM9 monolithic groups showed no strength degradation. For multi-layered specimens, when the porcelain layer was tested in tension (bi and tri-layers), the aging methods evaluated also had no effect on strength (p≥0.05). Total and partial failure modes were identified.Mechanical cycling and autoclave aging protocols had no effect on the flexural strength values and failure behavior of YZ and IZ ceramic structures. Yet, AL monolithic structures showed a significant decrease in flexural strength with any of the aging methods. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect