Effect of incorporating chitosan and propolis in dentifrices on the permeability and roughness of root dentin

This study investigated in vitro the effects of experimental dentifrices containing chitosan and propolis on the permeability and roughness of root dentin. Sixty cylindrical bovine dentin samples were divided into 4 groups: base dentifrice (BD), BD and propolis (DP), BD and chitosan (DC), and BD, chitosan, and propolis (DCP). The samples underwent erosion cycles (4 times daily with 0.3% citric acid) and brushing (2 times daily, 2 minutes each). Permeability and roughness were assessed at 2 times: postexposure of dentinal tubules and posttreatment with dentifrice and erosive challenges. Scanning electron microscopy (SEM) was performed qualitatively after treatment and erosive challenges at ×2,000 magnification. All groups exhibited reduced dentin permeability, with the DCP group showing the most significant reduction compared with the BD or DP groups ( P < .05). No significant differences in roughness were observed between the BD and DC or DP. SEM revealed that none of the tested dentifrices fully occluded dentinal tubules; however, the chitosan-containing groups showed a higher number of particles within the tubules. The combination of chitosan and propolis in a dentifrice effectively reduced dentin permeability without significantly affecting surface roughness.