The wear resistance of a commercial dental restorative composite exposed to different chemicals was measured with a pin-disc apparatus. The initial wear rate increased dramatically once the composite had been immersed in chemicals known to soften the cross-linked matrix material, which is a copolymer derived from BIS-GMA and diluent monomer. The increase of wear rate in a chemically softened composite was found to persist over a depth beyond 160 μm for specimens immersed over two wk prior to wear testing.
Get full access to this article
View all access options for this article.
References
1.
Wu, W.; Pestaner, J.; and Bowen, R.L.: The Softening of BIS-GMA Base Polymer by Chemicals with Different Solubility Parameters, J Biomedical Mater Res, In press.
2.
Brandrup, J. and Immergut, E.H., Eds.: Polymer Handbook, 2nd ed., New York: John Wiley & Sons, 1975, pp. IV-1.
3.
Dickson, G.: Physical and Chemical Properties and Wear, J Dent Res58:1535-1543, 1979.
4.
Alfrey, A.; Gurnee, E.F.; and Lloyd, W.G.: Diffusion in Glassy Polymers, J Polymer Sci C-12:249-261, 1966.