Related Experiment Videos
Photopolymerization of dental composite matrices
A Maffezzoli1, A Della Pietra, S Rengo
1Department of Materials Science, University of Lecce, Italy.
Biomaterials
|December 1, 1994
Summary
Dental composite polymerization generates heat, leading to non-isothermal conditions. Analyzing this using differential scanning calorimetry and kinetic modeling reveals higher reaction degrees and glass transition temperatures under non-isothermal cure.
Area of Science:
- Materials Science
- Polymer Chemistry
- Dental Materials
Background:
- Dental composite polymerization is often studied under isothermal conditions, neglecting significant heat generation.
- The exothermic nature of polymerization reactions in dental composites leads to complex, non-isothermal bulk behavior.
Purpose of the Study:
- To analyze the photopolymerization kinetics of a visible light-activated dental composite.
- To investigate the impact of non-isothermal conditions on cure behavior, degree of reaction, and glass transition temperature.
Main Methods:
- Differential scanning calorimetry (DSC) was used to determine the degree of reaction and glass transition temperature.
- A phenomenological kinetic model was integrated with an energy balance to simulate thicker composite layers.
Main Results:
- Non-isothermal cure conditions were achieved in thicker composite layers.
- Higher glass transition temperatures and degrees of reaction were observed under non-isothermal conditions compared to isothermal analysis.
Conclusions:
- Non-isothermal analysis is crucial for understanding dental composite polymerization.
- Optimizing cure conditions can enhance the final properties of dental composites, such as increased glass transition temperature and reaction degree.