The Wettability of Composite Resinous Filling Materials

The adhesive properties of the composite resins Adaptic®, Addent 12®, Blendant®, Dakor® DFR®, and TD 71® and of the non-composite resin Sevriton Simplified® have been studied by measurements of contact angles between solid surfaces of the resins and drops of six different test liquids. The results indicate that all the materials studied have low energy surfaces with very similar critical surface tensions. An analysis of variance showed the presence of statistically significant differences between the recorded angles of the different materials. These differences were, however, found to be smaller and probably have no appreciable effect on the adhesive properties of the studied materials. The inorganic phases of the composite resins were not found to have any influence on wettability. The free surface energy of all the resins studied was consisted of generally both van der Waal's dispersion forces and polar forces and/or hydrogen bonds. The influence on the retention of resinous fillings of the shrinkage during setting is discussed with reference to the adhesive forces found to form the free surface energies of the studied materials.