Atabak kashefimehr
, Samira Mohammad Mirzapour, Motahare Sharifyrad, Samira Beiraghi salek
*
Abstract
Background: Titanium dioxide (TiO₂) nanoparticles exhibit promising antibacterial and structural properties but raise concerns of cytotoxicity in oral soft tissues. Incorporating TiO₂ into biocompatible polymers such as poly(lactic-co-glycolic acid) (PLGA) may reduce these adverse effects and improve clinical applicability in periodontal therapy. Methods: TiO₂ nanoparticles were synthesized via a modified sol–gel method and incorporated into PLGA matrices with and without polyvinylpyrrolidone (PVP) as a stabilizer. The formulations were characterized using Fourier-transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), thermogravimetric analysis (TGA), dynamic light scattering (DLS) and X-ray diffraction (XRD). Cytocompatibility was evaluated using the MTT assay on human gingival fibroblasts (HGFs) across concentrations of 1–100 μg/mL after 24 and 48 h. Results: TiO₂ nanoparticles alone induced significant, dose- and time-dependent cytotoxicity, reducing cell viability to ~45% at 100 μg/mL after 48 h (p < 0.01). Pure PLGA maintained >90% cell viability at all tested concentrations. The PLGA/TiO₂ nanocomposite showed markedly reduced cytotoxicity, maintaining >80% viability even at 100 μg/mL. Incorporation of PVP improved nanoparticle dispersion, as confirmed by FESEM and DLS, and enhanced thermal stability of the composite. Conclusion: Encapsulation of TiO₂ within a PLGA matrix significantly mitigates cytotoxic effects while preserving structural stability, with PVP further improving homogeneity and heat resistance. These findings highlight the potential of PLGA/TiO₂ nanocomposites as safe and effective candidates for periodontal wound dressings, implant coatings, or regenerative scaffolds.