CaAm-P19: a novel amelogenin-derived peptide for enamel remineralization

Dental caries remains a prevalent global oral disease characterized by the progressive demineralization of dental hard tissues. Effective remineralization strategies are necessary to arrest its progression and repair the resulting structural damage. This study investigated a novel amelogenin-derived peptide, CaAm-P19, for biomimetic enamel remineralization. In vitro assays evaluated the peptide's cytocompatibility, structural stability and hydroxyapatite-binding affinity. The spatial distribution of fluorescein isothiocyanate-labeled CaAm-P19 was mapped using confocal microscopy, while overall remineralization efficacy was assessed in a demineralized bovine enamel model. Results indicated that CaAm-P19 was highly cytocompatible. BestSel deconvolution of circular dichroism spectra revealed that CaAm-P19 adopts a conformation dominated by random coils and β-sheets, and no statistically significant changes were detected following Ca²⁺ addition. Confocal imaging demonstrated continuous surface binding coupled with deep intralesional penetration exceeding 400 μm. Furthermore, the peptide attenuated calcium dissolution during demineralization challenges and directed the deposition of ordered hydroxyapatite-like crystals. Notably, CaAm-P19 achieved microhardness comparable to that of fluoride and significantly higher mineral density recovery. It successfully reconstructed a homogeneous micro-architecture, yielding a stoichiometric calcium-to-phosphorus ratio approaching that of native enamel. In conclusion, by combining deep lesion infiltration with targeted mineral nucleation, CaAm-P19 represents a scientifically robust and promising bioactive agent for early caries management.