The effects of desensitizing agents on dentin permeability using a hydraulic conductance device.

This in vitro study evaluated the effects of a sodium-fluoride varnish, two surface pre-reacted glass-ionomer (S-PRG)-containing agents, and an experimental glycerol-stabilized calcium phosphate cluster (GCPC) gel on dentin permeability using a custom hydraulic conductance apparatus. Horizontal 1-mm coronal dentin disks were prepared from extracted human molars, conditioned with 2% citric acid, and randomized to ClinPro Fluoride Treatment, PRG Barrier-Coat, PRG Pro-Care Gel, experimental GCPC gel, or distilled-water control (n=10/group). Hydraulic conductance was calculated at 3 psi from the time required for 50 µL of water to pass through each specimen. ClinPro and PRG Barrier-Coat significantly reduced permeability after the first post-treatment evaluation, whereas ClinPro and both PRG agents produced near-zero values after the second evaluation. GCPC yielded a moderate but significant reduction. Scanning electron microscopy findings were consistent with progressive dentinal tubule occlusion.