Evaluating the combined effect of a biomimetic organic matrix and bioinspired fluorapatite nanoparticles on initial caries lesions

Abstract

This study found that combining a biomimetic organic matrix of chitosan (CS) and carboxymethyl cellulose (CMC) with bioinspired fluorapatite nanoparticles (Nano-FA) significantly enhanced the remineralization of early enamel caries lesions. A total of 40 extracted third molars were sectioned into 200 enamel specimens and randomly allocated into five groups: sound enamel (baseline), demineralized enamel, CS-treated, Nano-FA-treated, and CS-Nano-FA-CMC-treated groups. Remineralization efficacy was assessed using Vickers microhardness testing, scanning electron microscopy (SEM), and energy-dispersive X-ray (EDX) analysis. Among all evaluated groups, both Nano-FA and CS-Nano-FA-CMC treatments notably improved enamel microhardness, restoring values close to those of sound enamel. The CS-Nano-FA-CMC group displayed pronounced mineral deposition on the enamel surface and a markedly higher Ca/P ratio (p < 0.001) than other groups. These findings indicate that the CS-Nano-FA-CMC composite is especially effective at promoting remineralization, likely due to synergistic action that results in sustained release of calcium, phosphate, and fluoride ions, and facilitates apatite formation. Within the limitations of this in vitro study, the developed nanocomposite demonstrates strong potential as a future biomimetic agent for managing early enamel caries lesions.