Related Experiment Videos
Release of formaldehyde from dental composites
H Oysaed1, I E Ruyter, I J Sjøvik Kleven
1NIOM-Scandinavian Institute of Dental Materials, Haslum, Norway.
Journal of Dental Research
|October 1, 1988
Summary
Formaldehyde release from polymeric composites was detected in all tested materials. Higher concentrations were linked to polymerization in air and surface inhibition layers, with release continuing for over 100 days.
Area of Science:
- Polymer Science
- Materials Science
- Analytical Chemistry
Background:
- Polymeric composites can release degradation products or unreacted constituents.
- Formaldehyde is a common releasable substance from certain polymers.
Purpose of the Study:
- To investigate formaldehyde release from nine different polymeric composite materials.
- To identify factors influencing formaldehyde emission, such as polymerization conditions and surface layers.
Main Methods:
- Analysis of formaldehyde (HCHO) using a hydrazone derivative.
- Quantification via high-performance liquid chromatography (HPLC).
- Testing of nine distinct composite material specimens.
Main Results:
- Formaldehyde formation was confirmed in all investigated composite materials.
- Highest formaldehyde concentrations were observed in composites polymerized in contact with air.
- A strong correlation (r = 0.83) was found between released formaldehyde and the thickness of the unpolymerized surface inhibition layer.
- Removing the inhibition layer reduced formaldehyde concentrations.
- Continuous formaldehyde release was detected for over 115 days, decreasing over time.
Conclusions:
- Polymeric composites can be a source of formaldehyde emission.
- Polymerization conditions and surface characteristics significantly impact formaldehyde release.
- Formaldehyde release from these materials is a prolonged process.