Abstract
OBJECTIVE: The primary objective was to evaluate the antibacterial and remineralizing effects of modified orthodontic primer containing nano-chitosan loaded with bioactive materials (gallic acid and calcium phosphate). The secondary objectives were to assess the physical, mechanical, and chemical properties of the adhesive primer. MATERIALS AND METHODS: The chitosan loaded with gallic acid and calcium phosphate was prepared and characterized by FESEM-EDX. Then it was mixed with Transbond XT primer at two different concentrations to prepare 3 groups: Control, 5 % and 10 % Nano-Chitosan/Gallic acid + Calcium Phosphate Primer (NC/GACP). The primer groups were evaluated based on their Shear Bond Strength (SBS), Adhesive Remanent Index (ARI), Wettability, Degree of Conversion (DC), Antibacterial and Remineralization properties. Statistical analysis was conducted using one-way ANOVA and Tukey's post hoc test, all significant differences were set at P < 0.05. RESULTS: The modified primer groups containing 5 % and 10 % NC/GACP showed a significant increase (P < 0.05) in SBS and DC compared to the control group, with no significant differences observed in wettability. The ARI scores were mainly 3 meaning all the adhesive remained on the enamel after debonding. Additionally, both modified primer groups exhibited significant antibacterial activity (P < 0.05). Furthermore, the 5 % NC/GACP primer group showed the highest calcium and phosphate weight percentages and Ca/P ratio compared to the other groups (P < 0.05). CONCLUSIONS: The orthodontic primer modified by nano-chitosan/gallic acid + calcium phosphate can be considered a novel antimicrobial and remineralizing adhesive that enhances the physical, chemical and mechanical properties of the adhesive.