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Updated: Mar 27, 2026
08:45
Shrinkage of Dental Composite in Simulated Cavity Measured with Digital Image Correlation
Published on: July 21, 2014
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Correlation between polymerization shrinkage stress and C-factor depends upon cavity compliance
Zhengzhi Wang1, Martin Y M Chiang1
1Biosystems and Biomaterials Division, National Institute of Standards and Technology (NIST), Gaithersburg, MD 20899, United States.
Summary
The configuration factor (C-factor) effect on polymerization shrinkage stress (PS) in dental composites depends on the testing instrument
Area of Science:
- Dental Materials Science
- Biomaterials Engineering
- Polymer Chemistry
Background:
- The configuration factor (C-factor) is often used to assess polymerization shrinkage stress (PS) in dental composites.
- Existing literature shows conflicting results regarding the C-factor's predictive power for PS due to cavity constraints.
Purpose of the Study:
- To investigate the complex relationship between the C-factor and PS using both analytical and experimental methods.
- To explain inconsistencies in previous research and clarify the clinical significance of the C-factor.
Main Methods:
- Developed analytical models based on linear elasticity to predict PS under varying instrument compliances.
- Validated analytical findings through experiments using a cantilever beam instrument with systematically altered compliance.
Main Results:
- A general trend showed decreasing PS with increasing C-factor in highly compliant instruments.
- This trend reversed, with PS increasing with C-factor, as instrument compliance decreased.
Conclusions:
- The correlation between PS and C-factor is critically dependent on the testing instrument's compliance.
- The conventional understanding that higher C-factors invariably lead to higher PS may be misleading.
- Cavity compliance must be considered alongside the C-factor to accurately predict PS in clinical scenarios.
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