Journal of Dental Research, Vol 55, 730-732, Copyright © 1976 by International & American Associations for Dental Research Online Journals
Diffusion of water in composite filling materials
M. Braden, E. E. Causton and R. L. Clarke
The uptake of water by composite filling materials seems to be a
diffusion-controlled process; the magnitudes of the diffusion coefficients
obtained are consistent with the uptake base through the resin matrix. The
diffusion coefficients measured show the diffusion coefficient to decrease
with increasing water concentration, which accounts for the protracted
nature of the attainment of equilibrium uptake. Diffusion coefficients are
generally lower in these composites based on difunctional methacrylates,
compared with methyl methacrylate, presumably because of the highly
cross-linked nature of the former.
