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Quasistatic Mechanical Testing for Computer-Aided Design and Manufacturing Occlusal Veneers Cemented to Milled Dentin Analog Material
Published on: December 20, 2024
504
Micromechanics of dental cement paste
Petr Dohnalík1, Bernhard L A Pichler1, Luis Zelaya-Lainez1
1Institute for Mechanics of Materials and Structures, TU Wien (Vienna University of Technology), Karlsplatz 13/202, 1040 Vienna, Austria.
Journal of the Mechanical Behavior of Biomedical Materials
|October 11, 2021
Summary
This study investigated Biodentine, a dental biomaterial, using nanoindentation and ultrasonic testing. Results show its superior mechanical properties are due to dense hydration products, though micro-defects are present.
Area of Science:
- Biomaterials Science
- Dental Materials
- Materials Science
Background:
- Biodentine is a calcium silicate-based dental biomaterial.
- It exhibits superior stiffness and hardness compared to construction cement pastes.
Purpose of the Study:
- To conduct the first systematic micromechanical investigation of Biodentine.
- To characterize its mechanical properties and identify factors influencing performance.
Main Methods:
- Grid nanoindentation (over 5700 data points for hardness and elastic modulus).
- Ultrasonic testing (over 300 tests in kHz and MHz regimes).
- Micromechanical modeling and homogenization.
Main Results:
- Biodentine's mechanical properties are described by three log-normal distributions.
- 74% of data indicate dense, calcite-reinforced hydration products (E > 60 GPa, H > 3 GPa).
- Lower density products and unhydrated inclusions were also identified.
- Homogenization predicted properties exceeding ultrasonic test results, suggesting micro-defects.
Conclusions:
- Biodentine possesses highly optimized mechanical properties due to its composition and hydration products.
- The presence of micro-defects slightly compromises the overall performance of this advanced biomaterial.
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