Related Experiment Videos
Color stability and hardness in dental composites after accelerated aging
Karen A Schulze1, Sally J Marshall, Stuart A Gansky
1Department of Preventive and Restorative Dental Sciences, Division of Biomaterials and Bioengineering, University of California San Francisco, 707 Parnassus Avenue, Box 0758, San Francisco, CA 94143-0758, USA.
Summary
Light-cured dental composites showed better color stability after accelerated aging than chemically-cured ones. Neither color change nor hardness increased significantly, suggesting better aesthetic durability for light-cured materials.
Area of Science:
- Dental Materials Science
- Polymer Chemistry
- Biomaterials Engineering
Background:
- Dental composites are widely used restorative materials.
- Assessing the long-term stability of dental composites under environmental stress is crucial for clinical success.
- Accelerated aging tests simulate environmental factors to predict material performance.
Purpose of the Study:
- To evaluate the impact of accelerated aging on the color and microhardness of chemically-cured and light-cured dental composites.
- To compare the aesthetic durability and physical property changes between the two types of composites.
Main Methods:
- Five chemically-cured and five light-cured composite materials were tested.
- Knoop microhardness and color (DeltaE*) were measured before and after accelerated aging.
- Specimens were aged using a xenon arc light and water in a Weather-Ometer for 122 hours.
Main Results:
- All composites exhibited a significant increase in microhardness after aging (p<0.05).
- No significant difference in hardness change was observed between light-cured and chemically-cured composites.
- All materials showed perceptible color changes, with DeltaE* values ranging from 1.6 to 15.5.
- No significant correlation was found between hardness and color changes.
Conclusions:
- Light-cured composites demonstrated greater resistance to color change after accelerated aging compared to chemically-cured composites.
- Light-cured materials may offer superior aesthetic longevity in clinical applications.
- Surface hardness changes were not directly correlated with observed color alterations in these composite materials.