Physicochemical Stability of Dentin-Derived Biomaterials During Long-Term Storage

Dentin-derived biomaterials are hierarchical collagen-mineral composites increasingly used as bio-based scaffolds for bone regeneration. However, the effect of prolonged storage of extracted teeth on their physicochemical integrity remains unclear. This study evaluated the stability of dentin-derived biomaterials following long-term refrigerated storage (up to six years) using Raman spectroscopy. Extracted human teeth were processed using three preparation systems (BonMaker, Tooth Transformer, and Smart Dentin Grinder), and Raman-derived indices describing mineral and collagen structure were compared with freshly extracted controls. No time-dependent changes were observed in mineral crystallinity, carbonate substitution, or collagen-related parameters, indicating preservation of the collagen-mineral interface during storage. In contrast, the observed differences were primarily associated with processing pathways. Tooth Transformer and Smart Dentin Grinder exhibited Raman profiles closely resembling native dentin, whereas BonMaker showed reduced mineral content and altered mineral-matrix balance consistent with its demineralization protocol. These findings demonstrate that dentin behaves as a structurally stable hierarchical composite, reflecting intrinsic structural organization that limits physicochemical degradation over time. Long-term storage does not compromise dentin integrity, supporting its use as a reliable source of biomaterial for regenerative applications and future tooth banking strategies.