Surfactant release from hydrophilized vinylpolysiloxanes
M Balkenhol1, S Haunschild, G Lochnit
1Department of Prosthetic Dentistry, Justus-Liebig-University, Schlangenzahl 14, D-35392 Giessen, Germany. markus.balkenhol@dentist.med.uni-giessen.de
Journal of Dental Research
|July 31, 2009
Summary
Surfactants improve hydrophilicity in vinylpolysiloxane (VPS) impression materials by leaching from the material, reducing surface tension. This study clarifies the mechanism of surfactant action at the liquid-VPS interface.
Area of Science:
- Dental Materials Science
- Surface Chemistry
- Polymer Science
Background:
- Vinylpolysiloxane (VPS) impression materials are hydrophobic.
- Surfactants are added to enhance hydrophilicity for use in moist oral environments.
- The interface mechanism of surfactants in VPS is not well understood.
Purpose of the Study:
- To investigate the mechanism of surfactant action at the liquid-VPS interface.
- To determine if surfactants leach from VPS materials.
- To correlate surfactant concentration with hydrophilicity.
Main Methods:
- Fabrication of four VPS formulations with varying non-ionic surfactant concentrations (0%, 1.5%, 3%, 5%).
- Measurement of contact angles on mixed VPS samples.
- Transfer of droplets from hydrophilized specimens to control specimens.
- Analysis of droplets using mass spectrometry.
Main Results:
- Contact angles showed an inverse correlation with surfactant concentration (p < 0.05).
- Droplets transferred from hydrophilized samples exhibited similar contact angles to the source material.
- Surfactant was detected in droplets from hydrophilized samples but not in the control.
- Surfactants reduced the surface tension of the contacting liquid without altering VPS surface properties.
Conclusions:
- Surfactants are leached from VPS impression materials.
- Leached surfactants reduce the surface tension of the contacting liquid, improving hydrophilicity.
- The study elucidates the mechanism of surfactant function in VPS materials.
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