Saturated anacardic acid preserves root dentin collagen under cariogenic challenge

Abstract Objective We aimed to evaluate changes in the structure and organization of root dentin collagen in bovine incisors pre-treated with an anacardic acid derivative (LDT11) following an in vitro cariogenic challenge, thereby contributing to understanding of dentin matrix biology and biomodification strategies for root caries management. Materials and methods Bovine root dentin specimens were demineralized and pre-treated with LDT11 (100 µg/mL) or distilled water (control). Samples were then subjected to a cariogenic challenge for 7 days. Histological sections were stained with Picrosirius and analyzed by polarized light microscopy to assess collagen organization and residual collagen area. Additional analyses were performed using Fourier Transform Infrared Spectroscopy in Attenuated Total Reflectance mode (FTIR-ATR) and thermogravimetric analysis (TGA). Results LDT11-pretreated samples showed a significantly greater residual collagen area compared to controls ( p < 0.01), with preservation of a dense and organized fibrillar network. FTIR-ATR analysis revealed spectral changes consistent with hydrogen bonding and collagen biomodification. Principal component analysis demonstrated clear separation between treated and untreated groups. In contrast, TGA showed no significant differences in total collagen mass loss, suggesting a localized effect of LDT11 at the superficial dentin layer. Conclusion LDT11 promotes preservation of the dentin collagen matrix under cariogenic challenge and exhibits potential as a collagen biomodifier through chemical interaction with the organic matrix. Its effects appear to be primarily surface-oriented, contributing to structural stability without altering collagen mass. Clinical relevance Potential of LDT11 as a dentin-interacting agent that can help control collagenolytic degradation as an adjunct for managing root caries lesions.