Age-related transparent root dentin: mineral concentration, crystallite size, and mechanical properties
| Autor: | John A. Pople, Robert O. Ritchie, T.M. Breunig, John H. Kinney, Ravi K. Nalla |
|---|---|
| Rok vydání: | 2005 |
| Předmět: |
Aging
Time Factors Materials science Biophysics Bioengineering Dentin Solubility Biomaterials Stress (mechanics) Fracture toughness stomatognathic system Hardness Tensile Strength Ultimate tensile strength Dentin medicine Humans Scattering Radiation Tooth Root Composite material Tooth Demineralization Aged Minerals X-Rays Microstructure Grain size stomatognathic diseases medicine.anatomical_structure Mechanics of Materials Ceramics and Composites Stress Mechanical Crystallite Tomography X-Ray Computed Synchrotrons |
| Zdroj: | Biomaterials. 26:3363-3376 |
| ISSN: | 0142-9612 |
| DOI: | 10.1016/j.biomaterials.2004.09.004 |
| Popis: | Many fractures occur in teeth that have been altered, for example restored or endodontically repaired. It is therefore essential to evaluate the structure and mechanical properties of these altered dentins. One such altered form of dentin is transparent (sometimes called sclerotic) dentin, which forms gradually with aging. The present study focuses on differences in the structure and mechanical properties of normal versus transparent dentin. The mineral concentration, as measured by X-ray computed microtomography, was significantly higher in transparent dentin, the elevated concentration being consistent with the closure of the tubule lumens. Crystallite size, as measured by small angle X-ray scattering, was slightly smaller in transparent dentin, although the importance of this finding requires further study. The elastic properties were unchanged by transparency; however, transparent dentin, unlike normal dentin, exhibited almost no yielding before failure. In addition, the fracture toughness was lowered by roughly 20% while the fatigue lifetime was deleteriously affected at high stress levels. These results are discussed in terms of the altered microstructure of transparent dentin. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect