Sodium alginate-polyethylene glycol paste loaded with zinc-doped tricalcium phosphate particles for the treatment of dentin hypersensitivity

β-tricalcium phosphate (β-TCP) has been widely applied in tissue engineering due to its excellent biocompatibility, degradability, and ability to induce mineralization. Zinc ion (Zn2+) displays excellent antibacterial properties and a vital role in regulating cell metabolism. In this context, the incorporation of Zn2+ into β-TCP to prepare Zn-doped β-tricalcium phosphate (Zn-β-TCP), emerges as a promising strategy for treating dentin hypersensitivity. However, delivering Zn-β-TCP effectively to the dentin surface for inducing mineralization of dentinal tubules remains a considerable challenge. In this study, we developed a sodium alginate-polyethylene glycol paste loaded with Zn-β-TCP particles, aiming to deliver Zn-β-TCP to the dentin surface for inducing mineralization. Zn-β-TCP particles were synthesized by the hydrothermal method and were combined with a sodium alginate-polyethylene glycol solution to create the Zn-β-TCP/sodium alginate/polyethylene glycol (Zn-β-TCP/SA/PEG) paste. In vitro experiments demonstrated that Zn-β-TCP could induce mineralization, exert good biocompatibility and antibacterial activity, promote dentin differentiation of dental pulp stem cells. Furthermore, Zn-β-TCP/SA/PEG exhibited excellent viscosity and effectively prompted the formation of a mineralized layer on dentin surfaces, successfully blocking dentinal tubules. Taken together, the present study demonstrated the potential of the Zn-β-TCP/SA/PEG paste as a promising therapeutic material for the treatment of dentin hypersensitivity.