Tideglusib-loaded hyaluronic acid hydrogels enhance odontogenic differentiation with adjunct low-intensity focused ultrasound

OBJECTIVES: Endodontic research is increasingly focused on biologically driven dentin-pulp repair. This study investigated a chemico-physical strategy combining a light-curable Tideglusib-loaded methacrylated hyaluronic acid (HA-MA) hydrogel with low-intensity focused ultrasound (LIFU) to support odontogenic differentiation of human dental pulp stem cells (hDPSCs). METHODS: HA-MA hydrogels were synthesized and characterized by ¹H NMR and Raman spectroscopy. The formulation was selected based on Tideglusib release, kinetics modeling, nanomechanical properties, and swelling behavior. Cytocompatibility, proliferation, Wnt-related and odontogenic gene expression, protein deposition, and mineralized matrix formation were evaluated. RESULTS: HA-MA synthesis was confirmed, with a degree of methacrylation of 28.5%. The 2% (w/v) formulation showed sustained Tideglusib release fitting a zero-order model (R² = 0.9477), higher elastic modulus than 1% (mean difference: 1.84; 95% CI: 0.87-2.81), and lower swelling ratio (mean difference: -6.38; 95% CI: -10.00 to -2.76). The selected hydrogel was non-cytotoxic up to 48 h, maintaining 94.6-113.8% MTT activity relative to control. Tideglusib-hydrogel + LIFU showed higher day-14 metabolic activity than control. Compared with direct Tideglusib administration, hydrogel-mediated delivery maintained AXIN2 upregulation for 10 days and enhanced sustained odontogenic gene expression, DSPP/DMP1 protein deposition, and mineralized matrix formation. Notably, Tideglusib-hydrogel + LIFU showed higher BMP2 expression at day 10 than Tideglusib-hydrogel, reaching 3.0-3.3-fold of control, and greater Alizarin Red S staining than both direct Tideglusib groups. SIGNIFICANCE: Sustained Tideglusib delivery from HA-MA hydrogels with LIFU stimulation supported odontogenic differentiation and mineralized matrix formation in hDPSCs. This strategy may offer a platform for biologically driven dentin-pulp repair and dentin-pulp complex regeneration.