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Published on: July 21, 2014
The effect of resin composite pre-heating on monomer conversion and polymerization shrinkage
Ulrich Lohbauer1, Spiros Zinelis, Christos Rahiotis
1Dental Clinic 1 - Operative Dentistry and Periodontology, University of Erlangen-Nuremberg, Glueckstr. 11, D-91054 Erlangen, Germany. lohbauer@dent.uni-erlangen.de
Summary
Pre-heating resin composites does not improve monomer conversion. However, reduced viscosity from pre-heating may enhance marginal adaptation, despite rapid temperature loss.
Area of Science:
- Dental Materials Science
- Polymer Chemistry
Background:
- Resin composites are widely used in dental restorations.
- Optimizing their properties, such as conversion and shrinkage, is crucial for clinical success.
Purpose of the Study:
- To evaluate the effect of pre-heating resin composites on monomer conversion and polymerization shrinkage.
- To assess these properties at different storage intervals and temperatures.
Main Methods:
- Fourier Transform Infrared (FTIR) spectroscopy measured the degree of conversion.
- Archimedes' principle determined polymerization shrinkage.
- Temperatures ranged from 10 to 68°C, with measurements at 5 minutes and 24 hours.
Main Results:
- No significant increase in monomer conversion was observed with pre-heating up to 68°C.
- Linear correlations were found between pre-heating temperature and polymerization shrinkage after 5 minutes.
- No statistically significant difference in shrinkage was noted after 24 hours.
Conclusions:
- Pre-heating resin composites does not enhance long-term monomer conversion.
- Reduced material viscosity due to pre-heating may offer clinical benefits like improved marginal adaptation.
- The clinical advantage is limited as the temperature quickly returns to physiological levels.
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