Remineralization And Antibacterial Potential Of Pasp-Acp@Hacc Film

To evaluate the dual function of polyaspartic acid-stabilized amorphous calcium phosphate@hydroxypropyltrimethyl ammonium chloride chitosan (PAsp-ACP@HACC) film in promoting dentin remineralization and inhibiting cariogenic biofilm. Seventy-two human mid-coronal dentin discs were demineralized in 37% phosphoric acid for 15 s. The samples were randomly assigned into 3 groups (n = 24): Group I (negative control): untreated; Group II (HACC): coated with HACC film; Group III (PAsp-ACP@HACC): coated with PAsp-ACP@HACC film. Twenty-four intact dentin disks served as blank control. Samples underwent 14-day incubation in artificial saliva with daily renewal of film and artificial saliva. Half samples underwent structural characterization (micro-CT, SEM-EDX, TEM-SAED) or mechanical testing (nanoindentation). Remaining samples were sterilized and incubated with S. mutans for 24 h. Antimicrobial efficacy was evaluated using live/dead staining and SEM. The data were analyzed using one-way ANOVA. The demineralized dentin treated by PAsp-ACP@HACC demonstrated intrafibrillar remineralization, exhibiting mineral content comparable to intact dentin (p > 0.05). Mechanical properties were significantly recovered, with elastic modulus and hardness matching intact dentin (p > 0.05). Bacterial assays demonstrated predominant dead bacteria on Group III surfaces, contrasting with viable colonies in Group I. SEM revealed compromised bacterial membranes on remineralized dentin. PAsp-ACP@HACC enables dentin remineralization and exerts potent antibacterial activity, demonstrating clinical potential for caries management.