Wettability of Modified Experimental Dental Adhesive on Dentin

Objectives: Surface wettability is an important predictor of bonding. Cellulose nanocrystal (CNC) and chitosan (CS) have been used to produce bioactive adhesives. These highly reactive molecules can be functionalized for improved wettability and bonding. The study aims to investigate the wettability on dentin of experimental resin adhesives loaded with functionalized (-F) and non-functionalized (-NF), cellulose nanocrystals (CNC) and chitosan (CS).
Methods: Experimental resin blends were loaded with CNC or CS, functionalized(-F) or non-functionalized(-NF) at 0.5%, 1.0%, 1.5% or 3.0% by weight (n=10). Flat dentin surfaces with standardized smear layer were etched with 35% phosphoric acid(15”) and rinsed. Dentin surface was positioned in Goniometer (Rame-Hart Inc) and 30µmL of adhesive was applied. Contact angle was measured for 1 min. Data were analyzed by one-way and two-way ANOVA, and Tukey test (p<0.05).
Results: Overall, CNC-NF and CNC-F were statistically similar to control resin blend (p>0.05), except for 3%CNC-F with the lowest contact angle (p<0.05). In contrast, CS-NF showed statistically higher contact angle than CS-F (p<0.05) overall, while both were similar to the control (p>0.05). Only 3%CS-F showed significantly lower contact angle compared to 3%CS-NF experimental groups (p<0.05).
Conclusions: The addition of CNC or CS in different concentrations did not show significant changes in wettability to dentin compared to the control. However, the 3%CNC-F and 3%CS-F formulations presented the lowest contact angle.