The efficacy of resin-compatible cavity varnishes in reducing dentin permeability to free monomer.

The effectiveness of three resin-compatible cavity varnishes in reducing the dentin permeability to free monomer liquid was evaluated by means of a dentin disk mounted within a pressurized split-chamber diffusion device filled with low-viscosity aliphatic dimethacrylate. Substantial reduction in dentin permeability was obtained with all of the products tested (Microjoin, Cavi-Line, and Universal). This study suggests their likely effectiveness as a protective barrier against permeation of free monomer into the dental pulp.