S-PRG filler extract solutions induce dentinal tubule occlusion and elemental incorporation in ground human dentin

Abstract

Abstract : Water-extract solutions of the surface reaction type pre-reacted glass-ionomer (S-PRG) filler forms precipitate when mixed with artificial saliva, suggesting their application as dentin desensitizers. This study investigated the dentinal tubule occlusion and elemental incorporation when ground human dentin was treated with S-PRG filler extract solutions followed by artificial saliva. Human ground dentin specimens were coated with SF0 (an S-PRG filler extract solution without filler particles) or SF50 (an S-PRG filler slurry containing 50% of filler particles) for 30 seconds and then immersed in artificial saliva for 7 and 28 days. The surface of the specimens was analyzed by scanning electron microscopy (SEM) and wavelength-dispersed electron probe microanalysis (EPMA). The SEM analysis revealed that both SF0 and SF50 induced the formation of insoluble deposits on the tubule openings and peritubular area. The deposits were most prominent after 28 days of immersion of the SF50-applied specimens. EPMA detected fluoride- and strontium-rich areas on the dentin surface. It was concluded that the two-step treatment (S-PRG filler extracts followed by artificial saliva) of ground human dentin induced dentinal tubule occlusion and uptake of fluoride and strontium, suggesting that the treatment may be effective in controlling dentin hypersensitivity.